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Franny
12-24-2005, 01:55 AM
Hi All,

I just received what I thought was going to be the build version of a Bird Of Time 3M sailplane. Turns out it is an ARF... A very nice ARF at that. The Fuselage is fiberglass with what looks like a reasonable hunk of metal in the nose. Anyway, I would like to convert it to electric and I was thinking of using an E-Flight 400 outrunner and a 3S 1320mA pack with a folding prop. I don't need incredible performance, just enough power to get up into the cleaner air here in Denver. The box sez 60oz, but that ofcourse will change. Whada ya think? 150W-ish? Also, I was thinking of retro fitting spoilers, but that may not be necessary. Dunno.

I'm guessing I would lop off the nose and install a bulk head and mount the motor from the inside. Add a spinner to the prop to replace the removed nose portion. Weight and balance might be an issue, but if there is as much weight in the nose as I think there is then it might not be such a bad swap.

I've never used a folding prop... Any suggestions? I'm thinking the CC speed controls can be programmed for a hard stop. Is this enough to get the blades to actually fold back?

I welcome all comments from you guys!

Thanks so much!!!

Franny

Jason T
12-24-2005, 04:35 AM
Franny,

What does the kit weigh out of the box? I would suggest at least 50watts/pound for the climb performance you are describing. If you can post at least an approximate weight I think we can help on the specifics.

Franny
12-24-2005, 05:55 AM
Sure,... The kit sez 60oz. So, subtract the nose weight and add the motor and battery and subtract the receiver pack and I'm not sure where we'll be ;)

Thanks!

Jason T
12-24-2005, 05:49 PM
So if the AUW is going to be roughly 60 oz then I would suggest a minimum of probably 200 watts. I am not sure how big the nose is on the BOT but you might be able to use an outrunner motor on it.

TeslaWinger
12-24-2005, 07:34 PM
Franny, I also went the same route. My ARF BIRD conversion began with sawing off ALL that lump of steel in the nose, allowing for some right and downthrust, and adding a ply bulkhead to mount the outrunner, which is forward of the bulkhead to restore the nose length. It required no additional lead to rebalance.

I made another nose skid blister from balsa and glass cloth, since the original gets cut off with the nose section, saving the belly from a lot of landing abrasion and helps keep the motor out of the dirt on landing.

Power is a Python 200HT outrunner, 200 watts. Anything less would not be real impressive. Battery is a ZAGI Hi Rate 1800 NIMH 8 cell, all the way forward. Prop is a Turbo Spinner (with a cooling hole in the nosecone) and a 14-10 CAM folder. The ESC is a Jeti Advance 30Amp. The ESC brake function is very effective and I have used it for all my E Sailplanes. It is an excellent feature- folding cleanly and restarting effortlessly.

It climbs ok but is not a hotliner- but weighs no more than the pure glider setup. I suggest no less than 200 watts- I actually peak out at a bit more than that!

I had considered using my two 2aH lipo 3 cell packs but they were a bit large for the space in the fuse and would have required extra weight to balance. The NIMH pack is good for just a few climbs but it stays up so well on a single climb that there is plenty of time to charge the other pack.

I had originally used a HS81 servo for the stab- but the gears stripped. I changed it to an HS-81 Metal Gear servo and all has been well since.

I love the way it rises in lift and is so easy to see, so graceful to turn, so willing to soar. I like it better every time I fly it. It has given me some very long enjoyable flights. The glide, handling and sink rate are very satisfying. Landing is a bit of a bear so I will be adding spoilers this winter. You will like this one!

I'll post a pic or two soon.

Enjoy,
TW

Franny
12-24-2005, 10:22 PM
Wow! How neat!! Thanks for all the great info. I can't wait to see your picts! So, sounds like the spoilers would be a good addition.

Thanks bunches!

Franny

TeslaWinger
12-26-2005, 06:20 AM
Welcome to the Venue of Vultures.

Here are my conversion detail pix. The lexan cover (painted white from the inside) really cleans up the nose section. It was made from a paper template trimmed to fit.

The scoop underneath was carved out of balsa block and feeds air to the cooling hole in the firewall for the batteries and ESC while providing protection for the motor.

The landing blister was balsa block carved and sanded to shape, glassed, painted and epoxied.

It was a thrill to find that with the small NIMH pack and motor/prop, it weighed exactly what the glider did with all that dead weight. I have 2 worn hacksaw blades that prove it is STEEL, not lead they have cast, and epoxied into the nose of a glider that could not self launch. Now that weight is put to far better use than merely balancing the tailfeathers! Penalty for adding electric power? None!

Be sure to cut the weight off the nose just aft of the metal with 5 degrees right and 5 degrees down - not cut thru it like I tried at first, thinking I might have to keep some of it. Forget that!

I relocated the rudder servo to the next to last bay in the fuse to allow any size battery pack to be used with a lot of fore/aft room for balance in the nose.

One useful feature is that the fuse balances in the same place with the wing on or off.

The small ZAGI 8 cell 1800 HiRate NIMH I use is made for twin Speed 400 foam delta speedwings and is the lightest battery possible to use- since it balances with it all the way forward against the firewall.

This is a very worthwhile project and a great ARF that is beautifully prebuilt. If they included spoilers and an electric option they would sell a million of them to 2 meter glider flyers who want a big glider that is easy to fly without a lot of expense- with the unique wing design of the Bird. Add the fact that electric conversion has no weight penalty and cutting into this beauty is well justified. Until they offer this gorgeous glider with power and spoilers, we will make this the perfect powerglider ourselves.

The idea behind the unique BoT wing planform is that altho the center section is the hardest working part of the wing, the airflow there is relatively stagnant. Increasing the aspect in the root section improves that. The side benefit of carrying a larger chord outboard with the BoT's unique 'trailing edge cut' is to provide more area to the heavily tapered tips which would otherwise be prone to tip stall in soaring turns. Simple elegance.

My EBoT showed no sign of being overly susceptible to tip stall- and soaring turns are a joy. Rudder/Polyhedral works perfectly for lateral control and the full flying symetrical foil stab couldnt be cleaner.

I love the workmanship and Monokote covering- which I will soon cut into to add spoilers so I don't need to worry about losing it to the lift- or the end of the field trying to land a sleek glass slipper that wants to do everything but land...


TW

Bill Hawthorne
12-26-2005, 05:27 PM
Try this.

http://www.rcgroups.com/forums/showthread.php?t=128251&highlight=Bird+time

Franny
12-27-2005, 07:52 PM
Thanks TeslaWinger!

So, are you pretty happy with that motor? There are so darn many to choose from... Oh, did you have any problems with cutting the fiberglass? Did you tape it up pretty well fiirst? This may be a job for Mr. Dremel. I really am psyched about this project! I have adored from a far the BoT for years. The kit looks to be of very high quality. I too will be adding spoilers as my field isn't super huge and model in the RealFlight sim acts like it has an anti-grav unit installed ;)

Thanks again for all int great info! I'll let you know how I progress...

Franny

TeslaWinger
12-28-2005, 01:12 AM
Yeah, Franny, the motor is fine- and there are a lot to choose from! Anything 200 watts or over will climb nicely- 300 watts would be a thrill to behold! I like the outrunner's simplicity since you can run a larger prop without a gearbox and its efficiency losses, weight and cost. Simplicity is its own reward- and larger props work much better.

Run the biggest prop you can and enjoy the gain in efficiency with larger disc area props. I have a 14"x9.5 folder and have a set of 18"x 10 for 6 cell use with the Marathon 200 HT- which I had misidentified earlier.. :D Thank goodness for labels!! LOL :D

I borrowed the ESC for my Queen Bee power conversion so the Bird is on vacation for a month or so! A set of Graupner spoilers will be accompanying the ESC on my next order just in case its gonna be Winter for awhile yet...

I used a hacksaw with fine teeth on the fuselage and the glass was just fine, wrapped in masking tape, cut in a miterbox with the fuse blocked in position.

The motor was mounted to the left of center on the firewall so the center of mass of the motor was in line w the fuselage, considering the 5 deg right and down thrust angle built into the firewall.

The lexan cowling strip cleans up the nose area- not as sleek as the original nose but still reasonably clean for a big blunt motor with serious cooling needs and power to spare!

Anti-Grav? I thought it was hydrogen in those gigantic wings...

I think it looks like a bass swallowing a motor... what it lacks in aerodynamic perfection it makes up for with character!

Enjoy,
TW

The mirror chrome finish on the motor is a nice touch...

TeslaWinger
01-02-2006, 08:24 PM
Thanks for the link, Bill. I didnt know there were other versions of ARF BoTs out there! The aileron version is strange with the flat wing! I am perfectly satisfied with polyhedral/rudder control and its inherent stability- even if it throws a bit of lift away with those upbent wings.

Franny
04-22-2006, 02:08 AM
Hi All,

Well, I finally finished the conversion. So, here is a run down:

I sawed off the nose and left about 3/8" of the steel nose plug for a bulkhead. The reasoning was two fold... I figured I would still need a little extra nose weight (I was right) and also, that seemed like a good diameter for the spinner. I ended mounting the AXI 2820-10 inside the fuselage. That was interesting, but I managed to get the steel firewall all drilled out. Steel is harder than wood. Must of forgot that somewhere along the way ;) Anyway, that left me the problem of cooling. I didn't want to add some huge scoop that would just add drag when I only need it really when the motor is running. Then it dawned on me... I could hinge the canopy and add a servo to the throttle channel and have the front raise and lower with the throttle. What do ya think? It turned out pretty cool. At full throttle, the canopy sticks up about 3/8" and when the motor is off, it is all the way down. The little set screw thingie is easy enough to take off and then I have access to my battery. I am using a 3S 3300 mAh Li Poly pack that fits in nicely. The other mod I did was to add magnets to the outer ribs in the wing panels so they will stay together. I actually used two magnets instead of a magnet and a washer for twice the holding power. I probably will augment with some scotch tape just to be safe. That’s about it... I'm running a Gruniper 11-6 folding prop. Maybe a little small for the motor, but I don't want things to heat up. I ran it for several minutes and the motor got a little warm, but the battery was cool and the speed control was fine as well and that is just a static test. I might think of putting the canopy servo on it's own channel and mixing it with the throttle so I don't forget to open it. Dunno... I'll have to see how it works in practice. I’ve included some pictures. I hope to fly it maybe Sunday? We’ll see. I have a late night gig Sat night and then there’s the weather. Holy Cow that is one big bird! ;)

Thanks!

Franny

vax6335
04-22-2006, 04:43 AM
That's an awesome idea. I've always loved the shapes of the BOT, and always wanted to get one. Someday I will, and I'll do an e-conversion too. Are kit's still available, or just ARF's?

Franny
04-22-2006, 06:00 AM
Ya know... I don't know... I thought I was biding on the kit version as I thought it would be easier to modify but they sent the ARF instead and it was so nice I didn't make a stink (also more expensive). There was a bad crack on the top of the fuselage starting at the front of the canopy, but I was able to patch it with epoxy and cloth and touched it up with Krylon H2O which was an amazing color match. I think I'm somewhere around 250W-ish. Neat kit. Well made and actually covered with Monokote. great quality and the ARF has a fiberglass fuselage - pretty sweet. All up weight is 66oz, so not too bad... I think the kit calls for 60oz. I'll let you know how it flys...

Franny

TeslaWinger
08-14-2006, 05:32 AM
No kidding! It is a great Bird for the money! That motor of mine turned out to be Russian junk and it ate the bearings!

I'll find another outrunner and redo the lexan motor fairing to smooth it in if need be.

I got 2 sheets of coroplast from a sign company and used part of one to make a coroplast carrying case with velcro closures to keep the Hangar Rash at bay! Plenty of room for the extra NIMH battery and a roll of tape for securing the outboard wings or even the tx and charger if you wanted to!

This is one bird that requires some serious thought if you wanna display it assembled! It is a MOOSE. A magnificent moose, like Bullwinkle! :D

Regards,
Rocket J Squirrel

Spoonwasher
02-12-2007, 06:10 PM
Hello Guys and Gals
I hope your still reading / reviewing posts on the Bot...I've jumped in and purchased one with the intent of making an e conversion. The motor I've chosen( st models- 2908-10) shows 240watts on the watt meter with a 10x6 graupner folder. 25/35 amp brushless speed control and I've made a 4200 ( 2100mah x 2 in parallel) lipo's from apogee)I mounted the pair -one on top of the battery tray-one underneath the tray..lifting off with the canopy...spring latch system added to the canopy. I cut the nose off with a diamond chipped dremel wheel with my dremel. I marked the fuse after measuring the depth of the steel into the fiberglass nose of the fuse.Used masking tape around the glass nose as not to chip & flake the glass. Worked well. I've epoied a ply firewall to mount the outrunner on. When I'm finished i can post some pic's if anyones interested.
DM

Franny
02-12-2007, 06:49 PM
Hi Spoonwasher!

Love to see your conversion! So, did you leave any steel? Is you motor mounted inside or outside?

I will be adding those Graupner pop-up spoilers very soon. I just got them from Hobby-Lobby and they look really cool. After I get those in and brace the main dihedral I'll be back in the air!

Franny

Spoonwasher
02-12-2007, 11:54 PM
Hi Franny...I took all the steel out..gone. I severed the fuse right at the rear of the steel in the fuse. It took me a week to get enough nerve to cut the fiberglass...I kept thinking if this doesn't work out I've ruined a beatiful plane. I finally did it and we are moving ahead.The motor will mount on the outside of the new plywood former/firewall. Cooling for the motor will be a non issue... if the drag from the motor is too great,I'll enclose it and hope the electrics will cool enough.I'll need a small scoop to vent/ cool the batteries & speed control. I do like that idea of hooking up the canopy to the throttle servo.quite inovative.I thought after I read this that I'd use my own canopy as an airbrake( taken from the servo to canopy idea. I'm thinking of installing an airbrake to help bring this bird down , at least before it gets to Denver ...I'm at work on lunch right now so when I get back home I'll start taking a few pic's to post.
Don

Franny
02-13-2007, 12:02 AM
Sounds good Don. I Like to see your break.

If it does head down here, let me know and I'll keep an eye out for it! I think mine could fly kilometers and kilometers at about 1.5 M off the ground...

f

batman
02-13-2007, 12:19 AM
Awesomke idea for the cooling, Franny. I hope I can remember it for when I build my first big electric sailplane. Thanks for sharing. Also, that motor should not let you down, it should have plenty of power. It may be worthwhile thinking about a 12 X 6 if you batteries can handle the amp draw.

TeslaWinger
02-13-2007, 01:53 AM
Welcome, Don- and congrats on finding the nerve to cut the beak off the Bird! Yeah, I remember the same feelings before the nosejob (am I having funnn?) but it went very well.

I used the forward mount but I must say I like Franny's internal mount. After burning up an internal Speed 400 once a month in my little Ascent I felt it was safer to let it breathe outside so I could push it hard on the climb. Keeping the motor forward let me forget about adding noseweight to balance it but its not the cleanest thing in town with the motor out in the breeze. Oh well, something had to give!

You're gonna love this one!

Denver? That ain't so far- Turn at Denver then glide in on final- or mount spoilers! :D

TW

Spoonwasher
02-13-2007, 06:11 AM
Well..home from work now and catching up on the posts.:D Thanks for the welcome Tw and Franny:) .I'll get the camera going here soon and post a few picks. Probably wont take too long as I've cleared the build table and I'm focusing on the Bot to get ready for a break in the weather & a first flight on the BoT.Now,Keeping my motor cool was first in my requirements so I chose the drag penalty of keeping things mounted out front and thought this would be an easier mounting choice. I also thought of spoilers too but being an arf and having to dig into the main spars and removing covering isn't high on my list. I'll have to see what the air breaking will do before we tackle that mod.
A thought occurred to me Franny, I could leave a message under the canopy incase the BoT strays a little.:rolleyes: Something like when people used carrier pigeons. LoL...anyway, hitting the hay now and we'll hit the build table in the morning.
Tomorrow will be a no fly day. It's predicted to be minus 20 with wind shield factor of minus 30:( .20c below presently this eve.For those in imperial measure..minus 20c = minus 20 F ....and i'm thinking I should have stayed 3000 kilometers to the south where I was last week at this time, in the Carribean Islands...That's cold even for us Canucks!:eek:

FoamCrusher
03-25-2007, 04:44 AM
I have just gotten my new BOT together - maiden flight tomorrow :D

Thanks to Franny's description and pictures, I got up enough nerve to cut the nose off and put in the motor. From a link on RCGroups I found pictures in the October issue of Soaring Digest that showed how to add spoilers. Thanks to a another local flyer who showed my how to use MonoKote, I recovered the plane in colors my older eyes can see at thermal height. A big thanks to all who have contributed to this thread and convinced me to get the BOT.

What it has:

Mega 16/15/3 in a Kontronic 5.2:1 planetary gearbox
3S2P MaxAmps 2100 HV lipos
HS-81MG for rudder servo, HS-65 for elevator servo
CC45, Hitech 555, Turbo Spinner and Aeronaut 15x8 folding prop. (16x10 on order)
Spoilers - Hand made 0.75oz glass/30 min epoxy blade held in place with rare earth magnets and lifted with HS-55 servos in a Y-harness.
AUW = 65 oz.
With the current prop MotoCalc says 66 oz of thrust @ 40 mph tip speed from 30A gives 1100 ft/min ROC. With the correct 16x10 prop it should give 78 oz of thrust @ 46mph at 40A with a ROC of ~1500 ft/min.

It should get about 7 min of WOT which is about 8 to 10 climbs to winch launch height. While not LMR performance, it should be entertaining :cool:

FC

FoamCrusher
03-25-2007, 08:15 PM
It was really too windy for a maiden, but I just couldn't resist.

Spool up the throttle, toss it into the air and it climbed right up - a little too much "up" because it seems that the three degrees down I put into the firewall is not nearly enough. Adjust the elevator/throttle mixing by putting in LOTS of down and it smoothed right out, climbing just fine on about 70% throttle. It may take a little adjusting the total amount of movement and size of the initial dead zone being mixed in before it will be neutral, but that is just a matter of dialing it in. The smaller 15" prop is very adequate and I might just keep it to decrease the current draw and increase the number of lifts. It needs full rates when under power to keep it under control.

Once to altitude and switching to low rates, after a little bit of trimming it just hung in the air...well like a bird; like a gull riding the uplift over the cliffs at the beach. The wind was very gusty from a base of about 6 mph up to 20 mph and the plane would rise and fall with the wind speed, but not make much headway. I could nose it down converting altitude into speed and bring it back to me, but at this weight it does not penetrate very well. We don't see conditions like this here very often and I have a Sleigers Electric Storm that is heavier with a SD 7037 wing that is much better suited to these conditions, so I won't ballast up the BOT. I will just bring the plane that matches the conditions..

After hanging in the air for a few minutes, I tried the spoilers. When they open to 90 degrees, the plane drops like a rock, going nose down about 30 degrees. Three bays long on the spoilers is plenty. Not wanting to take my eyes off the plane to switch the Tx over to the spoiler/elevator mix- without constant correction in the gusts the plane would change direction and roll a little - I brought it in for a nice smooth landing to do the adjustments.

After setting the Tx so I could dial in the up spoiler/up elevator mix on-the-fly with one of the Tx control knobs, I threw the BOT in the air again. Oh no! No rudder control :eek: I tried to nurse it to level by hitting the throttle, but no go. It finally rolled over and I could not bring it back, so it cartwheeled into the tall grass.

The keeper on the rudder clevis had broken (it was gone, probably breaking during the initial landing), allowing the clevis to pop off. When testing the control surfaces before the second launch, the rudder worked fine since the clevis must have still been attached, but open. When I asked for hard over rudder to compensate for a gust, it popped off, leaving me with no rudder control. On a R/E plane that can ruin your day.

Fortunately, there is only minor damage. I can feel at one place on the TE on the outer wing panel about half way down the panel where a rib intersects, the glue has popped off, and the sheeting forward of the spar may have broken along that rib. The covering in wrinkled but the spar feels solid. I will cut open the covering and drip in a little CA and it should be fine. This was a mechanical failure that I should have noticed on the pre-flight. I will probably switch to a metal clevis with a locking tab to prevent this from occurring again.

My initial impression is that I like the way this plane flys. It responds a bit slowly to control inputs from what I am used to, but it is a R/E/S 3m after all, so you would expect things to be a bit slower than on my super light 2M aileron plane. I will NOT be using it on windy days, however - without ailerons there is just not enough roll control. Even with what appears to be a very large rudder, the fuse is rather short for the wingspan and thus leverage is minimal, so the rudder lacks control in these conditions. To be fair, it was really too windy for this plane, and I knew it. In calmer conditions it will be a dream to fly.

FC

Franny
03-26-2007, 04:53 PM
Hi Foam,

Great to hear you got your BOT going. Sounds like the little mishaps were minor. I am switching everything over to metal clevises as well - much easier to adjust and a bit safer. I would agree about the winds and slow response to the rudder. I found that as well, but I think, as you mentioned, it was designed for thermaling and not for nuttyness. My BOT is finally on the bench and I have a pair of the "pop-up" Graupner spoilers to install.

Did you have any issues with the main dihedral? Also, how did your color scheme work out? Any flight photos?

Congrats on your conversion!

Franny

TeslaWinger
03-27-2007, 01:32 AM
Congrats, Foam! Wind sure does make for an exciting maiden! If only we could dial down the turbulence on those "Hey I can" Days!:D!

Glad you survived the rudderless flight! Whoa! Did that with an Ascent once- and was 'lucky' enough to have a wing warp to help with the directional control! :D

The BOT shines in low wind lazy thermals. I imagine adding spoilers slows the roll a bit in turbulence with a bit more inertial moment out there- but they sure can be lifesavers! This bird WANTS to soar! It is a prime candidate for a stratospheric thermal to confiscate - and you can watch it go for a lonnnng wayys if its defenseless against lift! :D

I've "been gonna" add spoilers but so far I have all the room I need to land where I fly now- and between the soaring, the roaring climb and the videopod downlink it won't be this season either!

I had the wing stripped down and the ribs flattened for the cheaper Graupner spoilers but realized I would have a big permanant flat spot on both wings at the high camber point. I restored it to its former camber and discarded that idea. I do like the popups tho so I might do them ... someday!

Til then, the Spring Air is bouyant and suddenly HERE! It's easier to transport in my lil car than my 2 Meter Aspire convert.

FoamCrusher
03-27-2007, 05:42 AM
Great to hear you got your BOT going. Sounds like the little mishaps were minor. Well, almost minor. I opened the covering tonight and the sheeting over the spar was punky so I had to splice in about a 6" long piece of new sheeting. Everything is drying now and I will patch on new sections of film tomorrow night. Not a big deal, but larger than I initially thought.
I am switching everything over to metal clevises as well - much easier to adjust and a bit safer. I have always liked plastic clevises since they are tighter on the threaded shaft and on control horns, but now I see their downside. I have an old metal one on my Electric Storm that has a separate metal locking tab and that is what I am going to try and find. They just DO NOT come off unless you take them off.

I have a pair of the "pop-up" Graupner spoilers to install.Those will certainly do the job. I was too cheap to pay 1/5 the cost of the plane for the fancy spoilers and made my own.

Did you have any issues with the main dihedral? Also, how did your color scheme work out? Any flight photos?Not sure what you mean about the dihedral. The laminated aluminum/ply/aluminum glued wing rods worked fine. They took a little sanding to get a snug fit, but otherwise the system seems to work great. I did not glue them in and remove them when transporting - less change of poking a hole in the covering of another part of the wing or one of the other planes in the truck.

I have used the same colors on other planes and it works very well. If I had had enough neon safety red to do more than just the tail I would have used that since it is much more visible, but the neon light green does the job. I did up a Multiplex EZ Glider with the tail, bottom of the wings, and bottom of the fuse in the safety red, with white wing tops and Krylon darker green neon spray painted wing tips and it looks like the colors are battery powered. No trouble telling which one is mine in the air and it is visible about 2X further away than the others at our field. My older eyes need all the help they can get ;) I should have taken up this hobby when I was younger and could see!

Sorry, no pictures. There was just myself and another flyer dumb enough to attempt flying that day so there weren't any "interested bystanders" to take pictures....and I was a little busy to try and fly with one hand and take pix with the other :rolleyes: Maybe next week if the weather is better.

Thanks to you and the others who combined all the information that gave me the courage to make the conversion. Although I still like EPP foam and its cousins like Elapor (thus the name), but I am sort of getting used to balsa dust. One of these days I may attempt a complete plane. Something like a Bubble Dancer or Big Bird.

FC

Franny
03-27-2007, 04:15 PM
Sounds good Foam. I'm a big fan of balsa and would have to say is my most favorite material to work with.

The Dihedral issue I was referring to is the center of the wing that was set at the factory (ARF). Mine made a loud crack on the maiden and I was just wondering if anyone else has experienced problems. I have a few large dia needles with a syringe (We have a 19 year old kitty that gets sub-Q fluids now and then) that I thought I would use to poke through and deliver some epoxy with out tearing the whole thing up. I think the sound was just the sheeting center joint cracking and not really a structural problem, but I can't be sure...

Hey, I have a question for you: Exactly where did you mount your flap servo? I just don't want to start cutting blindly through the center of the wing and run into something. I still have to figure out some kind of linkage.

Yeah, I know those spoilers are pricey... We'll see if they are worth it. I'll post some pictures as I get to it.

I would encourage you to go for it and build a kit from the ground up. It really is fun! You might also want to look into the Goldberg Gentle Lady. I just e-converted one I built a while ago and it is a dream to fly. It is kind of trainer like, but really soars well. With an E-Flight 400 or 470, it climes out quite well. They aren't very expensive either... There are soooo many gliders out there to choose from. I would say I have four; two "real" gliders and two converted free flights that are a blast to fly and are really unique in the sky.

Have fun in the sky. I'll be up there soon too...

Franny

FoamCrusher
03-28-2007, 01:46 AM
The Dihedral issue I was referring to is the center of the wing that was set at the factory (ARF). Mine made a loud crack on the maiden and I was just wondering if anyone else has experienced problems. Sorry, but I can't help you there. The center section sits reasonably well on the top of the FG fuse wing saddle. This is the three piece wing (the older ones were two pieces with the wing joined in the center) so it sits right where it is supposed to sit. The center section is already glued together and since it was not winch launched didn;t make any funny noises.

Hey, I have a question for you: Exactly where did you mount your flap servo? I just don't want to start cutting blindly through the center of the wing and run into something. I still have to figure out some kind of linkage.
I cut away the film between the ribs and left the sheeting alone. Starting from the panel joint to the outer wing panels, the first bay is actually a half width bay. I left that as is. My spoiler takes up the next three bays going toward the wing root, leaving two full bays untouched before the center wing sheeting. The spoiler blade is hinged on the sheeting with 3M hinge tape with the covering film over the top and covering the blade - sort of a poor man's live hinge.

See the pix below:

FC

Franny
03-29-2007, 08:16 PM
Hey FC, that is nifty! Looks like a little magnet action to keep it down until you need it. Sounds like they are pretty effective.

I opend up my wing last night and have started fitting the Graupners. They run 3 1/2 bays I think. They don't pop up all that high, so I'm hoping they will still be serious... I'm taking a few photos and I'll post them when I get it all done. My biggist issue is how to set up the linkages. each spoiler has a tab that stickes out one end to control the deployment. Just pull to deploy and push to retract and then a tad more to lock. I could mount a return spring at the spoiler end and use a single pull thread. This is the method I'm leaning towards. Other than that, I will need some type of rigid push rod. I am using a single flap servo mounted in the center of the wing like a strip aileron servo. I would rather not use two servos if I can get away with it as I already have a throttle servo (to raise the canopy when the motor is running), an elevator, and rudder. Since the spoiler servo will be lifting the spoiler vertically, it won't be pushing against wind resistance and won't need to be super strong. That is my theory at least...

I'll let you know how it turns out...

Franny

Franny
04-20-2007, 05:27 AM
Hi All,

Well, I finally got to installing the Graupner "Teck" spoilers for the BOT. These spoilers are meant to be controlled with a push-pull linkage from one or two servos. When the are down, the mechanism allows for a little additional travel which locks them in the collapsed position. The construction is lightweight Al for the most part. One of them worked very smoothly but the other required a bit of futzin' with because one of the little compression-fit pins kept working loose and jamming the mechanism. For $50 bones I was a bit bummed about that...

The installation was easier than I thought really. I removed the covering (pretty much all of the white on the center section) and cut a well for them in the ribs as far from the center as I could get them. I realized part way through that they would need to be a bit below grade and have a thin piece of balsa on top of them to attach the covering to and to allow a flush mount.

My next issue was just how to activate them... I wanted to use only one servo and there isn't much room in the center. I thought about two servos mounted in the wing and in hindsight, maybe that would have been the way to go. Instead, and just to be different I'm sure, I set them up to return automatically so all I have to do is to pull a line attached to them. I used a small piece if very small shock cord to supply the returning force. I then ran a control line to the center section and out through a couple grommets. The lines were attached to the servo arm and all it has to do is pull. Seems to work well. It does put a little strain on the servo, but they won't be up for long.

They do look cool and really have a very tiny footprint on the wing. I replaced the white and black trim and added some yellow to the bottom wing tips because I just couldn't tell which the heck way it was going on its first few flights.

As far as that audible *crack* I heard in flight, I had to get some glue inside without tearing everything apart. Well, I have a very old kitty named Spiro and he has had a few medical issues lately. Mostly he has been a bit dehydrated so the Vet gave me a fluid bag and I have administered sub-Q fluids several times. The needle for this can only be used once and is extra large. This, attached to a small syringe that his thyroid medicine comes in worked great for applying thin epoxy to the inside of the center section leaving only a few small holes. Thanks Spiro!

With all that taken care of, I believe the Bird is all set. All I need is the right day to get her back up. I'll let you know how it turns out!

Thanks,

Franny

photors
04-20-2007, 04:35 PM
Franny,

Nice job on the spoilers.
Bob

Franny
04-20-2007, 09:32 PM
Thanks Photors! I sure hope they work or I'm going to have to install a tractor beam to get this thing to finally plant its butt on the field ;)

Franny

Spoonwasher
04-24-2007, 10:53 PM
Excellent work Franny.I hope the spoilers workout well for you. I went more conventional, no spoilers but i figured if I need to the extra drag I'll kick up the motor at Idle and let the prop cause some drag.Now behind the scences ,my Dad recieved a BoT for Xmas...When I ordered one I new he'd love one so it made a great xmas gift under the tree. So he ,along with myself, have been putting along making our electric conversions.We have been very sucessful,maidened his today. It almost went straight up,he has the same setup as I ,2200mah 3 cell battery,35amp esc,10x8 graupner folder, brushless outrunner motor but no spoilers.A little breezy when he got up there but man did this bird want to soar.One climb on the motor is all we needed for the first 30min test.Now with out spoilers we were a little hesitant about getting the bird down, but just flew it too the grass with no issues.The one thing of note is it was a clear day,little cloud cover and that big white wing almost dissapears when you get it up there a ways,so some dark graphics will be applied to the underside of the wing . If you had to take your eye off it ,you just may never see the bird again.The white underwing blends very well into the stratus.I had to work yoday so Dad beat me to the maiden..being retired helped him get the edge on me...lol...When I & both birds and the two of us are together, I'll send you a pick....oh ya,just for your info Franny, he built an SE5a like mine,so he can be my wing man when we do low ground passes looking for that Triplane of yours...lol..
Great job Franny and nice to see more of your fine work
Don

Franny
04-24-2007, 11:18 PM
Hi Don,

That's great news! Glad you had great success! It sure does like to soar...

I was able to maiden (re-Maiden, if there is such a thing...) with the new spoilers. They worked great! Just pop them up and down it comes. In fact, I will be mixing in a little elevator (up) to keep the nose up. The exact opposite on powered climb - Mix in a bit of down to keep it from going vertical! It sure is fun though! It hooked a thermal a couple minutes out of the gate and floated and floated. The wing seems really strong now and my worries have gone away. It does fly a bit different than my Gentle Lady... The BOT rudder is really only very effective with a bit of airspeed. If it slows down too much, the turns can get awfully sluggish. It's all in the wrist I guess... I agree about the white wing... It couldn't be a worse color... I applied quite a bit of yellow to the bottom side of the tips and that help quite a bit although more would have been better and I might put a bit more on still.

Have fun with your Dad. Soaring is an activity best shared...

Thanks,

Franny

TeslaWinger
04-24-2007, 11:47 PM
It does fly a bit different than my Gentle Lady... The BOT rudder is really only very effective with a bit of airspeed. If it slows down too much, the turns can get awfully sluggish.

Franny

That's so true! My 2 meter gliders could turn tighter and recover from a momentary stall with much less fuss. The BOT likes to be flown like a big sailplane, keeping a bit more speed and being a bit less forgiving of flying too slowly.

I flew it with the video pod out in the breeze most of the last season but this spring I have flown it clean for several hours and went for some serious soaring. Got it too! I am still in awe of the way it rises in a level attitude and just goes up as it circles.

Light wind thermal soaring is my favorite style but I had an amazing day of wild rodeo air soaring on a small hill that focused my attention so intently that I had to land after awhile from sheer exhaustion! After 3 hours of wild wind soaring I was a very happy camper and went home smiling!

Glad you guys are having success with your BOTs and spoilers. She is a fine ship!

Green air to y'all!
TW

FoamCrusher
04-25-2007, 04:18 AM
I agree about the white wing... It couldn't be a worse color... I applied quite a bit of yellow to the bottom side of the tips and that help quite a bit although more would have been better and I might put a bit more on still.
See this article about how to pick the best colors so you don't lose your plane: http://www.ultimatecharger.com/color.html

The companies who put these planes together pick the colors to look great on the box or hanging in the LHS, not so you can see them from the ground when they are flying at 1000ft AGL. They are interested in selling planes and if yours flys away, they make another sale.

I bought a 2m sailplane that came all in transparent red. Man did it look sharp. The only trouble was I couldn't tell when it was upright or inverted. It now has BIG stripes added to the bottom of the wings.

I have tended to either having all black on the bottom of the wing or "invasion stripes", and use bright colors - safety orange, yellow, neon red-orange, safety green or stripes on the top of the wings, so I can see the plane. So far it works for me.

FC

TeslaWinger
04-25-2007, 04:54 AM
They are interested in selling planes and if yours flys away, they make another sale.FC


LOL! FORGET radio range! These weary peepers have the same limitation- if you can't see it you can't control it!

Tie a big yellow balloon to it! There goes the L/D!

photors
04-25-2007, 03:33 PM
I ALSO ADDED A TOOTHED GLIDER SKID TO THE FRONT. IT WORKS FAIRLY WELL AND REDUCES THE ADDED WEIGHT FOR BALANCE
bOB

Franny
04-25-2007, 05:00 PM
I've been wondering just what to do about that... I built a ply "chin" for the bottom and on my second landing I hit a rock and it just about sheered it off. At least it didn't hit the spinner!

Franny

Spoonwasher
04-26-2007, 01:26 AM
Thanks for the colour suggestions guys & galsI'm going to do something, just want to keep it pretty and something that suits the plane.Franny , I enjoy every chance I can get to go flying with my Dad, as i know all too well one day he wont be there so I definitly make the best of our outings.The bugger snuck out again while I was working today ,had the BoT up again and at our field landings on the grass are fairly easy and uneventful.You mentioned your gentle lady Franny,Dad & I have ward to getting mine up with him. My Lady works real well, 6 between us,they've been upfitted with electric brushless folders like our BoT's, Great plane for just simple soaring.Have a great time soaring guys and gals, the BoT is great
Don

Veber Chagas
07-31-2007, 12:29 AM
Read with interest your article on BOT conversion to electric. A few questions arise:
-which version are you now at and how the BOT flies?
- are there additional drag due to lack of motor cowl?
-have you ever tried a lipo battery and additional nose weight?
Thanks for your comment. Veber

Spoonwasher
07-31-2007, 01:05 PM
Hello Veber,
My BoT is the ARF version. I used 4200mah Lipo batteries(2x2100 20c 7.2 volts) and then added 5.5 oz of lead in the forward compartment to balance the bird. I kept everything in the cockpit as far forward as possible and used a hitec carbon gear micro servo in the tail. A tip here to help , twist the long servo wire lead wire to help reduce RF noise from the long wire lead going to the tail,this will help reduce glitching that may occur from the long wire leads in your plane.
Don

Dazzaz
08-01-2007, 04:00 AM
I just completed an Electra 2m with a brushless upgrade using a e-flite six series motor. The plane will go vertical on this setup and hits altitude in just a matter of 10 - 15 seconds. Using a 2200mah 3s lipo I can go out and fly almost all day long without having to re-charge.

I have been eying the BoT for a lonnnnnnng time now. After seeing this thread I think the BoT will be my next plane... The conversion doesn't look that difficult to do and I really like Franny's tech spoilers!

Franny
08-01-2007, 04:30 AM
Go for it Dazzaz! You're right, it isn't that hard. Even those spoilers weren't that difficult to get in. As ARFs go, it is a really nice one. If you do ARF-Bash, make sure you do something to those lily-white under-wings. It is a might difficult to see against a gray-ish sky...

Hey Veber? You might want to think about mounting the motor from the inside of the fuselage. It isn't that bad and it is a cleaner look.

Franny

Dazzaz
08-01-2007, 03:42 PM
Go for it Dazzaz! You're right, it isn't that hard. Even those spoilers weren't that difficult to get in. As ARFs go, it is a really nice one. If you do ARF-Bash, make sure you do something to those lily-white under-wings. It is a might difficult to see against a gray-ish sky...

Hey Veber? You might want to think about mounting the motor from the inside of the fuselage. It isn't that bad and it is a cleaner look.

FrannyActually... if I do go with the BoT I would be doing a kit build instead of the ARF. I really don't care for ARF's much especially the color themes they tend to use. Since I'd rip off the ARF covering anyway it would cost me more going with the ARF over the kit.

Do you think I'd be able to fit a 6 series e-Flite inrunner with a 3s lipo inside the fuse? I'm sure the BoT would take the place of my current Electra, so I'd like to use the equipment currently inside my Electra. Also, with the BoT rudder/elevator... is there a way to do a pull pull system? I have one on my Electra and love it as it has saved a lot of tail weight.

FoamCrusher
08-01-2007, 04:09 PM
Actually... if I do go with the BoT I would be doing a kit build instead of the ARF. I really don't care for ARF's much especially the color themes they tend to use. Since I'd rip off the ARF covering anyway it would cost me more going with the ARF over the kit.

Do you think I'd be able to fit a 6 series e-Flite inrunner with a 3s lipo inside the fuse? I'm sure the BoT would take the place of my current Electra, so I'd like to use the equipment currently inside my Electra. Also, with the BoT rudder/elevator... is there a way to do a pull pull system? I have one on my Electra and love it as it has saved a lot of tail weight.Dazzaz:

All the kit built and ARF's have in common are the wings and possibly the tail (unsure about the rudder foil). The ARF with the fiberglass fuse is very tail heavy so they put in a 15 oz iron plug in the nose to balance the plane as a glider. When you convert it to electric, removing the plug and replacing it with a motor/gb/battery is just about a wash, so balancing is not a problem. I imagine the balsa kit fuse is less tail heavy, but you should get input from someone who has built one.

The conditions where you fly might dictate how heavy you want the plane. My converted ARF came out at 51.5 oz for the fuse with servos but without motor/gb/battery. It is 66.7oz AUW; just about the AUW of the stock RTF glider version. At this weight it deals well with winds up to about 8 mph and can fly in winds up to 10 mph, but at over that there is just not enough rudder authority to control the plane- plus it just hangs in the air with no forward speed unless you convert altitude into speed. When I add a little weight it helps, but the lift is compromised. Lighter is better, but only to a point with this plane.

The twinned packs of TP-2100's will sit side-by-side or over-and-under with plenty of room, but this is the FG fuse.

FC

Dazzaz
08-01-2007, 04:19 PM
Dazzaz:

All the kit built and ARF's have in common are the wings and possibly the tail (unsure about the rudder foil). The ARF with the fiberglass fuse is very tail heavy so they put in a 15 oz iron plug in the nose to balance the plane as a glider. When you convert it to electric, removing the plug and replacing it with a motor/gb/battery is just about a wash, so balancing is not a problem. I imagine the balsa kit fuse is less tail heavy, but you should get input from someone who has built one.

The conditions where you fly might dictate how heavy you want the plane. My converted ARF came out at 51.5 oz for the fuse with servos but without motor/gb/battery. It is 66.7oz AUW; just about the AUW of the stock RTF glider version. At this weight it deals well with winds up to about 8 mph and can fly in winds up to 10 mph, but at over that there is just not enough rudder authority to control the plane- plus it just hangs in the air with no forward speed unless you convert altitude into speed. When I add a little weight it helps, but the lift is compromised. Lighter is better, but only to a point with this plane.

The twinned packs of TP-2100's will sit side-by-side or over-and-under with plenty of room, but this is the FG fuse.

FCHmmm... I thought that the kit built BoT still had the Fiberglass fuse. Perhaps I need to think a little more about getting the ARF and just strip it bare and recover. I really like the look of the FG fuse on the BoT and that is one of the reasons I want it.

FoamCrusher
08-02-2007, 06:12 AM
Hmmm... I thought that the kit built BoT still had the Fiberglass fuse. Perhaps I need to think a little more about getting the ARF and just strip it bare and recover. I really like the look of the FG fuse on the BoT and that is one of the reasons I want it.I seem to remember reading a post that the kit had a balsa fuse, but I could be wrong. Just to be sure you could call Tower Hobbies at 1-800-637-6050 and ask. The kit stock number is TG2525 at $64.99.

BTW, my latest Tower catalog came with a $15 off coupon for an order of $150 or more. That would be just about the cost of the ARF version at $139.99 plus some servos, folding prop or Rx. "Refer to AD #010GY - Enter this ad number into the yellow box on our web shopping cart." www.towerhobbies.com

If you are really into building a BOT you could buy a kit for the Big Bird XL with a 110" wing from Sky Bench Aerotech at www.skybench.com From what I have read it is a very high quality kit and can be made either with a balsa fuse or a FG pod with a CF boom. They have several sizes, down to a 2m MiniBird.

I would call and discuss options with them rather than depending upon their webpage since their presentation is not the greatest - lots of info but very poorly organized. If you poke around on it you can eventually get an idea of what they have. With the FG pod and CB boom I think the kit is about $300, where the Dynaflite kit is $65. Obviously there is a big difference in quality of the kit parts and you would get a premade fuse.

FC

Veber Chagas
08-15-2007, 01:11 AM
Spoonwasher and All: Thank you for valuable the information. I just wonder if the ARF BOT electrified can still be considered a floater in calm weather.This question is due to the increased weight of the fiberglass fuse and electric gear.

photors
08-15-2007, 09:31 PM
You will be quite amazed that the finished weight of the glass kit is 2 to 3 ounces less than the kit built without power. And yes, it still floats.
Bob

Spoonwasher
08-22-2007, 11:26 AM
hello Veber, Myself, I still consider this big bird a floater due to the wing span and wing loading.There are lighter more efficent planes but I enjoy this bird just the same.Very few days without wind here so far this year so the extra weight was neaded.

Spencer J
08-23-2007, 06:46 PM
Did that gearbox some with the mega? :cool: :confused:I have just gotten my new BOT together - maiden flight tomorrow :D

Thanks to Franny's description and pictures, I got up enough nerve to cut the nose off and put in the motor. From a link on RCGroups I found pictures in the October issue of Soaring Digest that showed how to add spoilers. Thanks to a another local flyer who showed my how to use MonoKote, I recovered the plane in colors my older eyes can see at thermal height. A big thanks to all who have contributed to this thread and convinced me to get the BOT.

What it has:

Mega 16/15/3 in a Kontronic 5.2:1 planetary gearbox
3S2P MaxAmps 2100 HV lipos
HS-81MG for rudder servo, HS-65 for elevator servo
CC45, Hitech 555, Turbo Spinner and Aeronaut 15x8 folding prop. (16x10 on order)
Spoilers - Hand made 0.75oz glass/30 min epoxy blade held in place with rare earth magnets and lifted with HS-55 servos in a Y-harness.
AUW = 65 oz.
With the current prop MotoCalc says 66 oz of thrust @ 40 mph tip speed from 30A gives 1100 ft/min ROC. With the correct 16x10 prop it should give 78 oz of thrust @ 46mph at 40A with a ROC of ~1500 ft/min.

It should get about 7 min of WOT which is about 8 to 10 climbs to winch launch height. While not LMR performance, it should be entertaining :cool:

FC

photors
08-23-2007, 09:57 PM
Yes, it came with the motor. From your description it sounds like you might be tail heavy. If so you might consider putting the elevator servo in the bottom of the rudder fin. Just where the 2" hole is.
Bob

FoamCrusher
08-24-2007, 02:53 AM
SpencerJ:

If you are asking about the Mega, then no, it is a Kontronic planetary box with the adapter to fit the Mega case. http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXGFN9&P=ML

Mega has planetary gear boxes but none with that deep a ratio. You can run a 16/15/4 in a 4:1, but the /3 at 5.2:1 allows a larger prop at the same current and better in-flight efficiency. I have been told, but never done it myself, that I could run a 17" prop, but it is waaaaaay over the motor's current limit. Mega's are good at that, but this is not for competition, so I keep it within specs. A 6:1 box would be even better, but the only one I found for this size motor case was a custom order job from Germany - not worth it for this bird.

Note: The Tower description is wrong when it comes to the shaft size of the motor that fits this gearbox. It says it is for a 3mm shaft but really the pinion fits a 3.17mm (1/8"). I had to cross reference it with the part numbers on the Kontronic website to be sure it worked and then just gambled it would fit. It did. I sent several emails to Tower about the error but they never have fixed the tech specs. I guess they just don't want to sell very many of them ??

I have found this combination to work very well on a wide combination of planes. Right now I have it in the BOT on 3S2P and in a Gentle Lady on 3S1P at 25oz AUW. It will lift just about any plane you can stuff it into.

It is not cheap, but like many things in life, well worth the $$$$ IMHO.

FC

Spencer J
08-24-2007, 03:14 AM
Ah.

Yes, you do get what you pay for. :) Very neat though. planetary gearboxes can really be up there $$$ wise...

FoamCrusher
01-17-2008, 05:44 AM
This thread has been dead for awhile and I just discovered something that might be of interest to those considering a BOT electric conversion.

I got a new BOT for Christmas because the original crashed into some trees and took out both wing tips (I found someone now with an extra set of tips and am negotiating for them - the original may fly again and I would have 2 complete planes....not a bad thing)

Anyway, when I got around to cutting off the nose to add the motor mount to the new fuse, I found that Dynaflite has done away with that big block of pig iron in the nose used to balance the plane and they have replaced it with some sort of hard black glue in which is embedded a hand full of 2mm steel ball bearings.

This conglomerate does not come out with one solid whack with a punch and hammer like the iron block did. It must be chipped out in little pieces with the tiny ball bearings coming loose from the matrix and falling all over the floor. It was a huge PITA to chip most of the goo out and then Dremel the inside smooth so I could glue in the motor mount.

I goofed with the fiber cutoff disk I was using to grind out the goo and made a single 10mm long slice all the way through the glass of the nose in one spot. That's not too bad since I reinforce the nose with a little glass cloth and 30 min epoxy since I use a rather high powered motor/gearbox. If I don't reinforce it, I can open the throttle too fast and twist the nose right off the plane.

The cut will be patched when I flair out the nose skeg since it gets cut in half when the nose it cut off, and no one will ever know it was there, but it did add a few more steps to the conversion.

I still love the way the plane flys which is why I got another. The conversion only takes beginner skills and a few evenings beyond making the glider version airworthy. Ultimately with two planes, even if one is damaged I can still have one to keep in the air.:D

If you have enough skill to not crash a glider very often this conversion is well worth the effort. If you are still crashing a little too frequently, start with a Multiplex Easy Glider which is far tougher and move up to the BOT as your skills improve.


FC

Franny
01-17-2008, 03:52 PM
Thanks FC,

So, they changed out that nose block... Interesting. Is it a bit bigger? I bet it would have to be. Well, thats a bummer... I used mine as the actual motor mount/heatsink. Will you be adding spoilers to your new one? Mine would be half way to Kansas before I got it down without them. It is cool looking in the air though... Did you make any color changes for visibility?

I will have the new receiver in my for this spring summer - can't wait. With the temps here in the single digits and teens, there isn't much thermal activity. Bummers... Another cool thing about electric is that motor can sit and sit and be ready to go without a bunch of cleaning. I'm really looking forward to some real stick time on the Bird this year. Have fun with yours!!!

Franny

FoamCrusher
01-18-2008, 05:53 AM
Franny:

My #2 is going to have a 2.4 GHz XPS setup while I will keep a Berg 5 in #1.

The block of glue is about the same size as the cast iron block and because it cannot be as heavy as the iron since it is mostly glue, that has me a little worried about the CG as well as the AUW. Is the fuse heavier? Is the tail heavier now and will the CG which was right on before with the packs I am using be so far off that I will need to add lead???? I will report back when I am finished.

And yes, the new one has my home-made spoilers like the first one. Since I wanted to be able to mix and match center panels and tips, I recovered the new set to match my old center panel - I think I posted a pix in this thread - with the burnt orange 70's top wing color replaced with Oracover safety neon green and the movable section of the rudder a safety red. The under side of the wings and tail are recovered all in black so I can tell top from bottom.

The one thing new I did do was when I had the covering off the rudder I thinned the rudder frame and ribs and replaced the material I removed with CF strips, just like the hight tech Eastern European planes. The caps are made from 0.003" thick x 0.250 wide CF strips cut to width and CA'd to the balsa. It is astonishing just how much more rigid that makes the tail - no twist at all when the control horn pushes and pulls on the bottom of the rudder.

Now I can see how shops like Vladimir's httphttp://airplane-model.com/ava.html:// can make such large and super light birds like the Ava. All that CF capping of the ribs allows you to use less wood and still have the necessary stiffness.

The Dynaflite BOT is no lightweight at around 60 -65 oz at 3.0m when compared to the Ava at the same weight but at 3.2m, but then again it only costs $140 vs. the Ava's $720 + shipping.

FC

photors
01-18-2008, 04:08 PM
i HAVE NOT SEEN THE "NEW" BOT, BUT I WILL TRY ONE. I WILL ATTEMPT TO HAVE SOMEONE HOLD THE FUSELAGE WHILE I DRILL THROUGH THE NOSE PLUG. I WILL START WITH 1/4 DRILL(VERY SLOWLY) AND SEE IF ENOUGH HEAT IS GENERATED TO POP THE PLUG. THANKS FOR THE HEADS UP

FoamCrusher
01-19-2008, 04:53 AM
I was holding and chipping all myself. It would certainly be easier with someone else holding the fuse.

I don't think heat is the answer (I don't think that goo is going to melt and if it did it would make a big mess) and drilling would be difficult with all those tiny ball bearings in the matrix. The drill bit would tend to grab and hold. If it caught it could either break the nose or hurt whoever was holding the plane.

The plug is some sort of cheap epoxy that crumbles more than chips when struck. It only took about 30 min to get it out, and about another 10 minutes with the Dremel to smooth the edges where the dark stuff stuck somewhat better to the fuse fiberglass. It is just compared to two or three good whacks with a hammer and steel bar to pop out the old pig iron plug, it was a major PITA.

What bothers me most is that this is a VERY good plane at a great price right out of the box, but they have done little things that are just "off". It is all the more frustrating since the changes would not cost a thing.

For example:

1. Cover the underside of the wings/tail in a dark color so the plane is visible at altitude. This is a 3m unlimited size plane, and once in a thermal it will spec out in a hurry. The white underwings are all but invisible against a cloud cover.

2. Dump the orange-brown accent on the top of the wings. Go with any light color....all white even, but yellow or light orange would be better, so you can see the plane as it banks.

3. Go back to the pig iron plug so it can be easily modified for electric flight. It is certainly easier to glue in place and is also less potentially toxic.

4. Skip packaging a bag of lead or iron shot with the plane. If I am going to adjust the CG, I will do it with lead weights. Use the money saved to make new molds for the fuse that are just a little thicker in the tail cross section to you can use a longer servo horn to get more throw on the elevator.

Anyway.....I am making the new motor mount tonight. Hopefully I can glue it in this weekend and the plane will be ready to fly next weekend.

Good luck with your conversion photors. Let us know how it works out.

FC

wing man9
01-13-2011, 01:14 PM
hi all Im new here and Im on my second Bot wow I thought chipping all the small BB's out was going to be hard, they came right out on the second strike , almost in one piece. my first Bot was a kit and I made a lot of FPV flights with it untill the wing broke in mid flight right as a friend showed up and told me some thing just came off my plane it was almost half the right wing. It was at 2000 feet up at the time. I had turned on the auto pilot to say hi to him. thats all that was keeping it flying straight untill I took controll and crashed into the ground at 80+ mph. I should have left the auto pilot on .
well I have the ARF now and I have been reading this forum for a time so I have some questions whats the best outrunner motor to use and how about the ESC . I plane to use 4s lipo's 2650mah each. the power plant is next up on the build so Im looking for some tips here. any one?
you can check out the flight video's of my last Bot on www.youtube.com (http://www.youtube.com) under camaro92026
may she rest in pieces

wing man9
01-16-2011, 09:31 AM
I am gonna be running a justable votage regulator to my vtx, they say 6 to 15 volts input power. so whats the best voltage to run the tx at. in the past I have used a 4s straight to the tx and rx but I think its best to regulat it to 15 volts . a 4s can have a voltage of over 16 volts . same with the vrx they say 6 to 15 volts input power. both should perform best at a specific voltage but what voltage . more voltage is not always better and every tx rx is different. the one Im using is a 5.8 modo 500mw vtx from www.iftrontech.com (http://www.iftrontech.com) and a yellowjacket 5.8 vrx.
should I use a voltage regulator on the reciever as well? my range was best with two 4s 5000 lipo's in parallel on the reciever and ground station ,and I used a 4s 3300mha flight pack that was also running the vtx. or was this to much voltage?

wing man9
01-16-2011, 09:31 AM
any one here?[popcorn]

rcers
01-16-2011, 02:22 PM
any one here?[popcorn]
Nope the thread you picked is over three years old! :)

kaindub
01-17-2011, 10:51 AM
Your anwwr will be on the suppliers website. Unfortuantely the links to the information on the suppliersd website does not work.
Contavct the supplier directly and ask the questions to them

oem flyer
01-20-2011, 02:40 AM
There is an excellent build thread on this same forum titled "Bird Of Time Electric Conversion" by sundevilpilot. It is the one that inspired me to build mine. Lots of great ideas and info.

kyleservicetech
01-20-2011, 05:53 AM
hi all Im new here and Im on my second Bot wow I thought chipping all the small BB's out was going to be hard, they came right out on the second strike , almost in one piece.

Many years ago I also used lead shot/epoxy for balancing a sailplane. When they were electrified, also had the problem of removing that lead shot.

Didn't take long to heat up the epoxy with a heat gun (In a ventilated area!!!) and digging out the epoxy/lead shot stuff with an old screw driver.

Nice thing about epoxy or yellow carpenter glues, they will "Let go" under high temperatures, in case you ever need to fix anything.

Don't try it with CA glue joints though. Doesn't work, and stinks like heck. Probably not good for your lungs either. (Don't ask how I know)

Edwal07
01-23-2011, 03:39 AM
Hi guys,
I know this thread is old but has new posts. I just got my BOT on Thursday and planning on the conversion. I have a G15 1250KV outrunner with a 45amp ESC and using 3S 30C 2650 lipos. I have read and looked over SunDevilPilots thread and love the pics. Franny also has a great thread so I plan on using both for the conversion. Will keep up to date on this thread if anyone is interested.

wing man9
01-23-2011, 08:35 AM
yes and Im doing the same and have fpv gear going into my bird so I can share the video's with every one. keep it alive here! I would love to see your build pictures as you get it built and share info too. 770kv or so motor and a 4s with a 60 amp esc and 12x10 prop. is a sure winner. I tried a 1200kv motor but it burned out at full out throttle with 4s and a 12x10 thats why I went with this 770kv motor on the kit bot but it may not fit in the ARF.
Im not sure yet if it will fit gonna try thou. you can run it full out till the battery quits to a mile up+. 5582+feet in 4 minuts or less with no burn outs. here is the monster moter 32 I used on the late BOT kit http://www.hobbypartz.com/monsterpower-32--770kv--outrunner-brushless-motor.html caution this cobo will cuz very high alt very quickly and turn your bird into a dot in the sky under full power. with out fpv gear you may loose sight of it up there. I love being above the clouds with my bird and fpv gear. the sun set from up there is a wow.
http://www.youtube.com/watch?v=L1KJUYb7Bqw
http://www.youtube.com/watch?v=twoBaCiFWnI

Edwal07
01-23-2011, 05:47 PM
Looks good to me. I will stay with the G15 as it is a cross of the AXI2820 and Eflite E15. I will use a 12x6 cam and spinner, on 3S that should be fine right at 500 to 550 watts. I don't need a zinger to get to altitude, I just want enough to get me into High Start range. We have good thermals here at times, some really monsters at one field I fly at, a couple of gliders have gone on to glider heaven in them never to be seen again.
I hope to start in the next week, I have vacation coming up and will be out of the loop for awhile. I also have a gasser I am trying to finish up also before then, just to get off my table.
Will post pics and updates when I start. Thanks for the info and look forward to the build's of yours and mine. Nice to have someone to share experience with.
Ed

wing man9
08-15-2011, 10:17 AM
check this out http://rangevideo.com/forum/showthread.php?p=16154

Leadchucker
08-16-2011, 04:19 AM
Just a heads up on flying a Watt-BOT, they don't do well when forced through a stand of hickory trees.

wing man9
08-17-2011, 12:48 PM
may it rest in pieces . sorry about your loss:sad:

kyleservicetech
08-17-2011, 03:41 PM
Just a heads up on flying a Watt-BOT, they don't do well when forced through a stand of hickory trees.

Ouch Ouch Ouch, a lot of glue needed here.

(Learned decades ago, absolutely never allow your model to fly below the level of the trees on the other side. Depth perception on anything more than 100 feet is lousy. We need to have our eyes about 5 feet apart!)

Leadchucker
08-17-2011, 05:38 PM
Thank you very much for the sympathies. This wasn't a case of depth perception per se, however it is the result of flat out pilot error. She was my backup ship for ALES competition and having dorked my main ship (Top Model Avia) two days before the contest, she went with. 7 planes ranged pretty far upwind circling in lift and one moments inattention I had keyed in on someone else plane and was "flying" it.

Meanwhile the Watt-BOT is off on her own with no pilot input and proceeded to screw herself straight down into a patch of hickory trees leaving parts amd debris from the tree crowns to the ground. I had though her profile would have been distinctive enough that getting mixed up would be a non event, actually I never even though about ever getting mixed up but it happened.

It's most embarrasing to crash at a contest in front of a gaggle of other pilots. And in fine sailplane people tradition, after retrieving the carnage I was offered at least 8 sailplanes to fly so I could continue in the event. I wound up flying my bud's OLYII that I built over 30 years ago and that I gave him to convert to an ALES ship.

kyleservicetech
08-18-2011, 01:05 AM
Thank you very much for the sympathies. This wasn't a case of depth perception per se, however it is the result of flat out pilot error. She was my backup ship for ALES competition and having dorked my main ship (Top Model Avia) two days before the contest, she went with. 7 planes ranged pretty far upwind circling in lift and one moments inattention I had keyed in on someone else plane and was "flying" it.


Reminds me of a sailplane cross country race in Illinois in the early 1990's. The course was 45 miles through country roads in one giant round robin. One guy set a record back then by flying his giant 14 foot wingspan sailplane six MILES! Yup, he was flying the wrong airplane. His model was found several days later by a farmer some distance from the launch sight.

They were flying so high with these models, if you took your eye off the model, you'd never find it again. One was verified by a full size plane at over 5000 feet.

I was there, saw it happen. :(

Desertdog
09-30-2011, 11:24 PM
I recently bought a futaba 7 fasst 2.4 with a 617 reciever so i could fly longer distances away from me and at a higher altitude. What a fantastic bird this makes as i can fly at much greater distance and feel more confident. i also adjusted the rudder throw to the third notch in to make it turn tighter. I adjusted the duel rates at 50% on swich d so when im just soaring around i can make gental turnes. I also got rid of the bag of fishing weights in the nose and used stick on tire weights and slid them up under the motor to get more weight up front reducing the cg by overall weight. also if you use meguires paste wax i think it makes it cut through the air better and turn better?

cliffkot
09-23-2014, 03:27 AM
I ordered a BOT from my LHS that I'm planning to electrify. Went to pick it up last week but discovered (in the shop) that UPS had shortened the fuselage by a half inch so a replacement was ordered. However, I was rather dismayed at the absolutely horrible Monokote job done by the factory. All the edges were badly wrinkled.

Is this normal? Can it be fixed? I wasn't figuring on the additional cost of covering - iron, heat gun, material, etc. Plus I wanted the ARF because it was an ARF. What is it supposed to look like? I have never done any covering so your inputs would be appreciated.

Cliff :confused:

rcers
09-23-2014, 01:28 PM
...However, I was rather dismayed at the absolutely horrible Monokote job done by the factory. All the edges were badly wrinkled.

Is this normal? Can it be fixed? I wasn't figuring on the additional cost of covering - iron, heat gun, material, etc. Plus I wanted the ARF because it was an ARF. What is it supposed to look like? I have never done any covering so your inputs would be appreciated.

Cliff :confused:

Cliff that is super common, especially with Monokote. The issue is the work is done (and quite well actually) in the factor in China. Here is what happens next:



It is more humid there and drier here - stuff shrinks and wrinkles form
Wood is typically a bit greener it dries and shrinks
It comes to the USA in a super hot shipping container, yep more shrinking
It sits in a warehouse, gets shipped out
Sits for a year on the store shelf (not a hot, moving item)

You get it - wrinkle city.


I have only had ONE ARF ever not needing work.


You should be OK using the home iron, or a travel iron to re-shrink. Super simple! Search YouTube for Monokote vids - there will be good ones... And yes it can be completely fixed (98% of the time).


Mike

Yakfishingfool
09-23-2014, 06:01 PM
Had the same, put in a good war movie and sat down with an iron and cleaned her all up in a matter of an hour or so.

cliffkot
09-24-2014, 12:01 AM
Cliff that is super common, especially with Monokote. The issue is the work is done (and quite well actually) in the factor in China. Here is what happens next:



It is more humid there and drier here - stuff shrinks and wrinkles form
Wood is typically a bit greener it dries and shrinks
It comes to the USA in a super hot shipping container, yep more shrinking
It sits in a warehouse, gets shipped out
Sits for a year on the store shelf (not a hot, moving item)

You get it - wrinkle city.


I have only had ONE ARF ever not needing work.


You should be OK using the home iron, or a travel iron to re-shrink. Super simple! Search YouTube for Monokote vids - there will be good ones... And yes it can be completely fixed (98% of the time).


Mike

I guess I just didn't expect the need to "fix" an ARF kit, especially one that hadn't even flown! Yakfishingfool, I'll probably work on it while watching a new episode of Downton Abbey.

rcers
09-24-2014, 12:20 AM
ARF does not equal zero work. Try building that beast from plans (yes I have) and you will feel fine with 15 mins of iron time. :)

cliffkot
09-25-2014, 12:26 AM
QUOTE=rcers;957926]ARF does not equal zero work. Try building that beast from plans (yes I have) and you will feel fine with 15 mins of iron time. :)[/QUOTE]

I hear you. Thought about getting the kit, but I just don't have the time in my life right now for a project like that. Once I retire the story will change, but until then I have to follow a simpler route. In any case, the ARF is certainly not a bad deal. It does weigh more, but you get a fiberglass fuse out of the deal. Besides, it's awful pretty lookin'.

rcers
09-25-2014, 01:56 AM
Yep, same here, hard to get the time even for an ARF. I look forward to more building time in a few years (if I can actually ever retire LOL).

You will love the way this flies too! It handles the extra weight just fine.

Mike

cliffkot
09-25-2014, 11:32 PM
Yep, same here, hard to get the time even for an ARF. I look forward to more building time in a few years (if I can actually ever retire LOL).

You will love the way this flies too! It handles the extra weight just fine.

Mike

Mike,

Do you happen to know exactly what the ARF BOT weighs WITHOUT the lead in front? Haven't been able to find that spec anywhere.

Cliff

rcers
09-26-2014, 02:30 AM
Not sure but as is the case with most, nose weight is needed. I would not worry too much.

cliffkot
09-28-2014, 09:50 PM
Picked up the BOT at my hobby shop yesterday. The owner took care of the mess involved with the first one that was damaged in shipment and got it replaced in less than a week. What a difference. The covering on the second bird was absolutely flawless. (Many thanks UPS. You did me a favor this time.)

Although this is going to be an over-winter project, I had some time and the wife was out of town so I couldn't resist gluing up the wing braces. I had no idea what a 3 meter plane would look like in the house. This thing is simply gorgeous. Can't wait to fly it.

rcers
09-28-2014, 11:00 PM
Awesome sounds like the 2nd ship is MUCH better....

Those ARF's that sit on the shelf for months/years are tough on the covering. Yours will likely wrinkle a bit but again - it is a quick touch up. :)

Mike

cliffkot
09-29-2014, 03:39 PM
Is there any real CG or weight benefit achieved by moving the elevator servo from the back to the front? When you consider the extra hardware needed, it seems it would be a wash, unless you could also eliminate some of the ballast up front.

Any opinions?

Cliff

cliffkot
10-11-2014, 03:52 PM
The weight of a bare BOT fuselage is 12.05 oz. (342g). This weight does not include the portion of the nose cutoff to remove the ballast shot (20g). For further clarification , this is the weight of the fuse alone without ballast, servos, control rod(s), rudder, horizontal stab, etc. Just the fiberglass with integral wooden shelves and spacers.

The weight of the shot and glue plug is 8.4 oz (238g)

Measured on a Soehnle scale with accuracy of 0.05 oz. or 1.0 g.

Hope this data will be of help to all ARF BOT builders.

cliff

Crashchez
06-30-2015, 03:26 AM
Thanks to all for the info on BOT upgrades and conversions.
I bought my BOT arf about a month ago and still haven't had her maiden, due to the upgrades. So far I have added a scratch built bellcrank for the elevator then moved the servo foreward. Aluminum plating for the bellcrank and bailing wire for the control rod. Then I finally got the nerve to cut the nose off! I've made the motor plate, and will be epoxying it soon.

Up&Away
07-01-2015, 08:35 AM
I am now on my 2nd e-BoT. Lost the first one to flutter at more than speck altitude.

I've written extensively on the "other" forum, and there's also a write up in the December 2007 RCSD issue.

The BoT is a lovely glider when balanced properly. In both I installed spoilers in the top of the wing, with the spoiler hinged on top of the main spar. I easely compete with her in local friendly F5J competitions, and only loose out in so-so weather conditions. Spot landings take a bit more care than with full house wings, but it can be done.

A word on the bellcrank; make it as large as humanly possible. The flutter death I had with my first one allmost certainly came from a malfunction of the small bellcrank I had installed. My current BoT has a HS65 in the tail.

The Monokote it comes in is on the heavy side, and can be replaced with lighter Ultracote.

Crashchez
07-07-2015, 12:43 AM
Thanks Up&Away!
I'm always trying to new tips all the time. I'm taking your suggestion about making a larger bellcrank for the elevator.
As for my progress with the motor insall: after I dremel cut the nose off, I removed the steel ball blob with my air chisel... Hee hee. Stuff flew everywhere! I love safety glasses. That took but a half minute to get it all, without damaging the fiberglass.
The motor istall was a success. The CG was way off, so I made this new blob with the steel balls and epoxy, which is held in with velcro.
Maiden will be within next few days...181216

181217

Crashchez
07-21-2015, 12:21 AM
Maiden flight on July 18th. I would have to say it was a success for sure. The wind was very calm, and there was minimal trim adjustment.
I really loved how she glided. After the first trip getting some elevation, I was able to keep her up for around 15 minutes or so. Total flight time was about 40 minutes on one 2200 MiliAmp battery. There is currently an 11X7 prop, so I'll have to upgrade to a 13 or 14 inch.
Now I'll have to mount my GoPro...:D

Larry3215
07-21-2015, 06:54 AM
Congrats!

kyleservicetech
07-21-2015, 10:20 PM
Thanks Up&Away!
I'm always trying to new tips all the time. I'm taking your suggestion about making a larger bellcrank for the elevator.
As for my progress with the motor insall: after I dremel cut the nose off, I removed the steel ball blob with my air chisel... Hee hee. Stuff flew everywhere! I love safety glasses. That took but a half minute to get it all, without damaging the fiberglass.
The motor istall was a success. The CG was way off, so I made this new blob with the steel balls and epoxy, which is held in with velcro.
Maiden will be within next few days...181216

181217

Really nice job on the motor installation on your model :D :D