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-   -   Advice please- Large slow stick (http://www.Wattflyer.com/forums/showthread.php?t=73346)

swaps 03-15-2014 09:12 PM

Advice please- Large slow stick
 
Hi all,
Im looking to scale up a slow stick to a 4ft (48") X 9" cord wingspan made with correx corregated plastic. The type SPAD planes are made of. Im wanting to get at a minimum 30 minutes flight. Im still a learner so most flight will be at half throttle or less but I do want a lot of power so if I get in trouble I can pull the nose up and power my way up high and safe. Im expecting fully loaded the plane may be 1 -2 lb. Can anyone give me a guide to what power brushless motor, speed controller size and battery would be the best fit ? I know slow sticks are usually very low on weight and battery power but I have no problem with hanging a plastic box under the plane for the extra batter weight. Thanks for looking.

Alan

Mivins 03-15-2014 09:47 PM

Large Slow Stick
 
1 Attachment(s)
Hey Swaps: You are in luck, check out Chellie's Slow Stick build from 2010. I built one over a year ago kinda like it, and my 6 year old grand daughter drives it around in the sky. Mine will fly til your neck is tired on a 2200 mah 3S battery. It flys well at about 1/4 throttle and has way too much power at full. You can hand launch in rough terrain by just holding it up giving it about 2/3 throttle and let go it'll go straight up. (I used a Hobby King Turnigy ST3007 Donkey motor and Turnigy 35 amp ESC.) Way too much power, but then I like to have enough power to get out of trouble, like when the little one is heading straight at the cell tower in her back yard. Attachment 174068;)

Check out the link for a plan and a scheme. If you have a Dollar Tree store near you their foam board is much lighter than cardboard, and very cheap and easy to work with. If you are in a hurry use hot glue, if you are not use Elmer's Carpenter Glue. I took the paper off the foam for the wing, but left it on for the ribs, (easier to draw on).

http://www.wattflyer.com/forums/showthread.php?t=16392

swaps 03-15-2014 10:08 PM

Thanks, Just what I needed. I can get hold of foam board but the corregated plastic is much stronger so thought I would use that but may consider a change.

Thanks Alan

Mivins 03-15-2014 10:33 PM

4 foot slow stick
 
4 Attachment(s)
Swaps: I don't want to bore you to death, but thought I'd send you some more details on the Foam Stick. I've flown mine to death and back and its one of my favorite planes. I recently built a new wing using the original carbon leading edge spar, and center mount made from scrap ply.
Attachment 174069
The plane with 2200 mah battery is just under 29 oz all up weight. That's with the 2nd wing which has ailerons and two more servos than the original three channel version. Note I used drywall tape to reinforce the center glue joint, and a strap underneath to prevent any twisting and it also is under a bit of tension to add washout to prevent tip stall on slow lazy turns.
Attachment 174070
I stuffed the rudder and elevator servos on kinda facing in to make the control rod runs a straight shot. I didn't use any tubing to contain them, just some drink straw guides glued to the 1/2 x 1/2 stick. Radio, ESC, and battery held on with zippy ties. (There is a ton of room to experiment with CG changes.)
Attachment 174071
Ultralite weight 3" wheels and tires are made from scrap liteply and foam caulking bead. Motor mount from scrap ply. I used 4-40 screws and blind nuts from Home Depot to mount the tail, the wing, the motor.
Attachment 174072
Good luck, if you have any more questions drop me a note, I'm on most all the time I'm not fishing, flying, or riding the bike. Retirement is good for me. :ws:

hayofstacks 03-15-2014 10:45 PM

My stock wing slow stick fly's for 30-45 minutes on easy throttle with an 11x8.5 prop on a headsuprc 480 plus motor and 2200 3 cell battery. its a bit of a porker now, weighs just over 30oz.

My only question, why build up a corroplast wing for a $25 airframe? I've used mine in several streamer fights with between 3 and 5 slowsticks and there is hardly a scratch on it. I've had probably at leaks 5 head on collisions with it, and everytime I've been able to land it without any real damage. Twice without even a motor mount.

If your using the stock fuse, glue a dowel into the center with the foam expanding gorilla glue. adds weight, but you will almost never have to worry about it splitting or twisting again.

swaps 03-15-2014 10:54 PM

Hi,
This will be a scratch build, I don't have anything at the moment just working out what I need. I can get foam board but only in A2 size anything bigger is too expensive over here. I can get the correx about half the price and its comes in 8 x 4 sheets so just a straight cut across for my wing and plenty left for another plane when I'm ready. It would just be easier and cheaper than foam board and from what I have read over here the paper is real hard to get off. its not the same as your dollar tree board.

Alan

fhhuber 03-15-2014 10:55 PM

The coro will be heavier than the foam-board even if you can find 2mm coro. More weight = higher minimum speed to sustain flight and more power needed to maintain that airspeed. If duration is your goal then minimizing structural weight will be important so you can carry more battery.

Note that more battery will actually reduce duration after some point. You can only find that point by experimenting.

swaps 03-15-2014 11:06 PM

Hi,
Yes, I know it will be heavier but also more crash resistant and I think 30 mins fight time will be enough. As long as I can get that I would be happy. I can always have a spare battery if I have not has enough and giving the motor time to cool will help the lifespan too.

Thanks

Alan

fhhuber 03-15-2014 11:20 PM

If it is not overloaded you can run your motor continuously and never overheat it.

Mivins 03-15-2014 11:20 PM

large stick
 
I tend to agree with Fhuber, the foam is more than just a little lighter, it is incredibly strong after its bent, and probably 1/5 the weight, depending on the thickness. I would consider using cardboard sheeting such as my beer carton plane, or some other single thickness cardboard, maybe sheeting both the top and the bottom will make it very strong. I'd still use some kind of foam for the ribs as they're so easy to cut and shape, and much cheaper than balsa. My small beer carton stick wing has been cartwheeled numerous times and is still flying.:) Where are you located that they don't have any kind of foam board for mounting posters and photographs?

hayofstacks 03-15-2014 11:34 PM

My opinion, don't bother with an ubdercambered wing. its very draggy and not very efficient. if you want it to fly for a long time with minimal power, you'll need something like a sail plane wing. I doubt you could build that out of correx and have it strong and light. I use 4mm correx for my tail surfaces on my slow stick, and it works very well and is extremely tough.

If you make the wing strong enough, it will carry plenty of weight with a ubdercambered wing. my plane weighs nearly 12oz more then my first slow stick. You could easily add another 2200 3 cell and have the same weight as my slow stick, almost doubling fight times. but you will have to keep it light

fhhuber 03-16-2014 12:38 AM

For slow flying... underchambered + saran wrap n tape = flat bottomed.

Underchamber for really slow flight is just fine. The drag isn't an issue until you get more airspeed. You can easily experiment with the saran wrap to see which works better for your plane.

swaps 03-16-2014 09:32 PM

Thanks guys
 
Hi all,
To be honest I was going to go with a single sheet flat cambered wing or possibly a Kline–Fogleman stepped aerofoil. Any view on these ? or would underchambered be better ?

Thanks Alan

swaps 03-16-2014 09:38 PM

I can get A2 foamboard but everyone over here says its very hard to get the paper off, needs to be soaked. anything above A2 size is about $8 a sheet. Im in the UK. I can get polystyrene and depron but both of these are very brittle so not great for me as I do expect to crash more than a few times. Most of my experience is on RC flight sims.

Alan

Quote:

Originally Posted by Mivins (Post 942642)
I tend to agree with Fhuber, the foam is more than just a little lighter, it is incredibly strong after its bent, and probably 1/5 the weight, depending on the thickness. I would consider using cardboard sheeting such as my beer carton plane, or some other single thickness cardboard, maybe sheeting both the top and the bottom will make it very strong. I'd still use some kind of foam for the ribs as they're so easy to cut and shape, and much cheaper than balsa. My small beer carton stick wing has been cartwheeled numerous times and is still flying.:) Where are you located that they don't have any kind of foam board for mounting posters and photographs?


swaps 03-23-2014 10:32 PM

Marty.
Thanks for the advise. I have just bought the ST3007 Donkey motor you recommended. Got another month or 2 here before we get some flying weather so hope to have a slow stick built and ready to go when the good weather arrives.

Thanks Alan

CHELLIE 03-23-2014 10:44 PM

Hi :) This is a very Fast Build and Cheap Like me SS, just 1 sheet of Dollar tree Foam board 2- 3/8" bass wood sticks and some 1/4" bass wood sticks, for a wing frame and some 5 min epoxy and your out flying in no time :)

http://www.Wattflyer.com/forums/atta...2&d=1171937869

http://www.Wattflyer.com/forums/atta...0&d=1171966221

http://www.wattflyer.com/forums/atta...8&d=1172535694

the wing screws on so you can move it around to get your CG

http://www.wattflyer.com/forums/atta...1&d=1172535694

http://www.Wattflyer.com/forums/atta...9&d=1172954970

CHELLIE 03-23-2014 10:49 PM


Mivins 03-24-2014 01:53 AM

Motor advice
 
Swaps: Advice is really cheap, but thanks are very appreciated. I think unless you build a lead sled you will be happy with the performance of the ST 3007. I have stuck my big slow stick in the dirt hard enough to shear the wing just off the center through the foam, and glued it back together and had it flying the next day. I was really impressed with the fact that the motor took a nose in first with enough impact to snap the wing and not damage that motor. When I was have landing gear issues, I could hold the plane stationary and give it full throttle and it would fly away without even a toss. Good luck, and happy flying.;) Marty

swaps 03-25-2014 10:35 PM

Sounds perfect, was C rating do you use on the LIPO ? I will get a 2200 mah 3S but not sure of the best C rating.

Thanks Alan

Quote:

Originally Posted by Mivins (Post 943432)
Swaps: Advice is really cheap, but thanks are very appreciated. I think unless you build a lead sled you will be happy with the performance of the ST 3007. I have stuck my big slow stick in the dirt hard enough to shear the wing just off the center through the foam, and glued it back together and had it flying the next day. I was really impressed with the fact that the motor took a nose in first with enough impact to snap the wing and not damage that motor. When I was have landing gear issues, I could hold the plane stationary and give it full throttle and it would fly away without even a toss. Good luck, and happy flying.;) Marty


swaps 03-25-2014 10:37 PM

That's looks nice and just the sort of thing I am aiming for !

Thanks Alan

Quote:

Originally Posted by CHELLIE (Post 943421)
Hi :) This is a very Fast Build and Cheap Like me SS, just 1 sheet of Dollar tree Foam board 2- 3/8" bass wood sticks and some 1/4" bass wood sticks, for a wing frame and some 5 min epoxy and your out flying in no time :)

http://www.Wattflyer.com/forums/atta...2&d=1171937869

http://www.Wattflyer.com/forums/atta...0&d=1171966221

http://www.wattflyer.com/forums/atta...8&d=1172535694

the wing screws on so you can move it around to get your CG

http://www.wattflyer.com/forums/atta...1&d=1172535694

http://www.Wattflyer.com/forums/atta...9&d=1172954970


fhhuber 03-25-2014 11:05 PM

C rating isn't really important any more with all packs being 20C or better. How often do you plan to demand enough power to drain the packs in under 3 minutes?

Sure you can get marginally more power with higher C, but for the aircraft you are working on it won't matter.

Back when you might commonly find 4C or 8C rated packs, you did need to watch to ensure the packs could deliver the current you were going to demand.

hayofstacks 03-26-2014 03:41 AM

Higher c packs generally weigh more as well.

CHELLIE 03-26-2014 08:09 AM

this motor will work great

http://www.headsuphobby.com/Emax-Mul...ombo-E-121.htm

motor mount

http://www.headsuphobby.com/Stick-Mo...tors-A-205.htm

esc

http://www.headsuphobby.com/HURC-22-...-ESC-E-126.htm

lipo

http://www.headsuphobby.com/111v-150...tery-F-120.htm

lipo charger if needed

http://www.headsuphobby.com/Emax-EC-...rger-E-103.htm

Rockin Robbins 03-28-2014 12:09 PM

All these posts are from normal sized Slow Sticks. Here's a guy who wanted to attend the DeLand Festival of Giants where mondo expensive planes hang out and try to impress each other, but he wanted to show them that flying pleasure is unrelated to the number of dollars in the airframe. So he built an 8' Slow Stick.
YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.


Of course the details aren't in the video but you could shoot the man a message and get the lowdown. Note that it is definitely a Slow Stick in appearance and flying characteristics.

CHELLIE 03-28-2014 12:15 PM

Thats a Nice Big SS :D :D :D


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