Converted from rubber "Sparky"

[ZL3VML]

I built this especialy for SoS and was concerned some about how it would turn out weight wise. I gotta say I am impressed with both the model and my efforst. Somehow I dont think I will build another in a hurry though.... too fiddly for my ham fisted mitts!

The Sparky is a 32" rubber model by Ed Lidgard (1941) and has micro radio and 2s 350mAh LiPo's and a homewound cdrom drawing 2A on full throttle.
Weight is 5.3oz and all tissue covered but with laminating film on the fuse as well.

A good climbout (I am disappointed by the very limited range of the radio though) and about 20-30 minutes flying time per charge depending on thermals etc. Whoo-hoo ! what a blast to have it slowly circling around overhead just like a proper rubber one. :D

Mark

[Sky Sharkster]

To ZL3VML, Hi Mark, Welcome to the O/T'er Forum! Great Job on the "Sparky"! I know what you mean by "fiddley", every time I build an Old Timer I swear I never want to see 1/16" square balsa again, but somehow I keep coming back for more.
If the limited radio range is still an issue you might want to check out either the new micro Berg RX from Castle Creations or the sub-micro RX from FMA Direct. Both are full-range FM's. I'd hate to hear a strong thermal took that beauty away!
We have a twice-sized "Sparky" flying here, built from a short kit. Powered with a "2800" series AXI outrunner, covered with Ultracote Lite transparent. Flys very well, R.O.G.'s, floats around in a stately manner, won't come down; Just like the original!
Good Luck!
Ron

[ZL3VML]

Thanks Ron.

I did look at them before I started but as I allready had the rx I decided to use it. I will try lengthening the antenna wire and see if I can improve it somewhat.

Yes - thermals are allways a worry :(

Hmm - 2x Sparky sounds like a damn good size. Might be just the thing for my next A-Texaco :D

We are looking at changing the local rules to fly both electric and gas models in the same events and on equal footing - but somehow I dont think it will be a simple process.

Mark

[ZL3VML]

Hey - just came across this old thread so thought I'd update.
Sparky is still floating around, a real joy to fly.
I lengthened the antenna - doubled it, to around 42" and had to wind it around the fuse to stop it hanging out the back.
The range is fantastic now.

Flies best on about 1/3 throttle and being just gently steered around.

Mark

[jeffb]

Mark,

What type of wire did you use to lengthen the antenna? Was curious. Also, do you know of a site that would have specs on some of the older kits from guillows? In particular a 1976 spitfire? Thanks,
jeff

[ZL3VML]

Jeff
I just used some thin orange wire I have. It is the same colour as the fuselage so not easily seen in the air.

Guillows kits - sorry, I have no info on them at all.

Mark

[chaz345]

Mark,

What type of wire did you use to lengthen the antenna? Was curious. Also, do you know of a site that would have specs on some of the older kits from guillows? In particular a 1976 spitfire? Thanks,
jeff
Guillows appears to be alive and well and still producing their old kits.

Is this what you are looking for?

http://www.guillow.com/GuillowDetail.asp?UID=2992159&prod=403&SeriesId=20&FamilyId=1

[normblitch]

To ZL3VML, Hi Mark, Welcome to the O/T'er Forum! Great Job on the "Sparky"! I know what you mean by "fiddley", every time I build an Old Timer I swear I never want to see 1/16" square balsa again, but somehow I keep coming back for more.
If the limited radio range is still an issue you might want to check out either the new micro Berg RX from Castle Creations or the sub-micro RX from FMA Direct. Both are full-range FM's. I'd hate to hear a strong thermal took that beauty away!
We have a twice-sized "Sparky" flying here, built from a short kit. Powered with a "2800" series AXI outrunner, covered with Ultracote Lite transparent. Flys very well, R.O.G.'s, floats around in a stately manner, won't come down; Just like the original!
Good Luck!
Ron

I seem to recall a published article/plan on a 2X E-Sparky; can anyone jog my memory??

Norm

[WingTips24]

cool lookin planw looks like a real floater

Tips

[Eric_N57105]

I seem to recall a published article/plan on a 2X E-Sparky; can anyone jog my memory??

Norm

It appeared in the July '83 Model Aviation (AMA rag). Plan #00414. Not cheap, $19+shipping. A small version of the plan is included in the article so you might have some luck enlarging it.

Skybench has a short kit and a full kit for it. Probably the one Ron was talking about in his area above. The kits don't include the plan, so it gets pricey pretty quick.

http://www.skybench.com/electkit.html

There's also a Sparky ARF @ 57". Can't vouch for it, but the photo looks pretty good.

http://www.acehobby.com/ace/TTR4307.htm

I ordered the AMA plans. Love that big pointy snout!

Eric

[Dereck]

Hi folks
THis is fascinating stuff - I have an old KeilKraft Senator 32" rubber FF kit I hauled over from England when we moved here in 1994. I recall buying it because I always wanted one as a kid, but could never afford it - it was one of KK's biggest and priciest!

Of late, the idea's been growing to build one off the plan - keeping the kit intact to eventually pay for my retirement by e-baying it :D - and add three channel RC and a baby lecky motor.

Struck me I could even trim some weight - it has 1/8" square longerons, etc, to take the strain of a pretty hefty rubber motor. 3/32" would probably do for an electric.

Have most of the RC gear lying around - the motor and battery will take some researching I suspect. While the idea of building motors is intruiging, it's way beyond my spare time these days. Have to scrat around, see who's peddling RTR versions.

Was chatting with Dave Robelen last weekend at an indoor meet - he had a couple of tissue covered large scale models of OTs and the covering was superb. Turns out, no smelly dope involved. Tissue stuck on with Elmers, shrunk with rubbing alcohol (okay, that's a bit smelly) to tighten and then sprayed with a couple of coats of dear old clear Krylon from a hardware store.

Thanks for the prod!

Regards

Dereck

[Sky Sharkster]

Hello Dereck, If you want to get that Senator flying, there's one RTR motor I can recommend, the HiMax 2208-1260
http://www.maxxprod.com/mpi/mpi-26.html
I've been running this in a (5/8th Scale) 33" W.S. Playboy Sr. pylon version for over a year now, it's great! Quiet, powerful and trouble-free. The Playboy has 2 Hitec HS 50 servos, FMA Direct M-5 micro RX, Hacker 9A ESC (Too big, but it's what I had in the drawer!) and 2s 840mAh LiPoly (also too big, but the model needs nose weight), covered with Microlite transparent red + Opaque white. RTF weight slightly over 7 ounces, but could be lighter.
As a side note, this is the second version I've built, the first was tissue-and-dope finish with a LensRC CD Rom motor. Had to retire that one, too many puncture/patches and the tissue has faded to light pink.
Here's a couple more links to micro motors, both RTR and DIY:
http://www.strongrcmotors.com/
http://www.gobrushless.com/store/cgi-bin/cp-app.cgi?usr=51H5288847&rnd=1310092&rrc=N&affl=&cip=207.200.116.130&act=&aff=&pg=cat&ref=motors
Also some photos of the twice-sized Sparky (photo # 4. 38)and the Playboy (# 11, 34). In # 49, third from left, the CD, Travis McGinnis is holding his Sparky and directly beneath him, facing the camera is Jerry T's version. I'm to the right of Travis, with the Playboy.
http://imageevent.com/sipphoto/events/vintagefly2006
Good Luck!
Ron

[Dereck]

Hi Ron
Thank you for the links. I'll have to look that one up - though my kit mountain is being whittled down (mostly by sales), I am hanging on to the "Senator". If it takes to being steered around - FF models can be iffy about that - I have one indoor venue handy for odd trips out in public. Strikes me, the hardest part will be hanging a motor inside the nose to start with and then keeping the profile the same.

I suppose I could take a leaf out my old RC scale book and make a 'scale' prop of rubber motor sizes to put on for pits posing duties ;) ? Stop it sitting there looking odd with an itty-bitty e-power prop on it.

I've been running a couple of motors from Model Airplane Engineering http://m-a-e.com/ These are ready-mades that I understand are close relatives to CD ROM motors (could be wrong on the latter though). With Castle Creations T'bird 9 ESC, I have been pleasantly surprised by how well they 'throttle down' compared to some of my larger outrunners and by their power. My 17T on a mere 7 x 4 was taking my 31" span Cobweb II vertically to the rafters in the National Building Museum, on all of 2S.

Something new to do at last! I never fancied building the Senator for a whining geardrive

Regards

Dereck

[Eric_N57105]

Got the AMA Plans (#414) and Sky Bench short kit two weeks ago. Wing and tail went together with no problems. Because of the 50" length, it was tough keeping the fuselage straight during the build

Out of the blue, a friend e-mailed me about Olen Rutherford's tip on page 116 of the Mar 07 AMA mag not knowing I was scratching my head about how to build a jig at that very moment. I happened to have the issue sitting on a file cabinet where I had quickly tossed it after thumbing through it.

Olen made cardboard "formers" for 3 stations of his Piper Super Cruiser. I made mine a little differently. First I drew them up in CAD, printed them out and pasted them on foam core board. I made them all the exact same outside dimension, 6x7". The foam core makes them strong and allows accurate cuts. By making them the same dimension, once they were in place, I could work on the fuse right side up, upside down or on either side and it would still lay perfectly straight. You can take out any twist by pinning the formers to the board or by quickly hotgluing temporary battens or stringers along the side of the formers.

The Sky Bench short kit eliminates the tedium of cutting accurate ribs and fuse formers, but Sparky is still mostly a pile of sticks. The plans are reasonably clear, but there are still enough puzzles to figure out to make it interesting.

The short kit included laser cut firewall parts. Unfortunately, they were cut for a huge Astro 05 (this was 1983), so I made a new one for the much smaller outrunner I plan to run. I mocked it up in Alibre Design Xpress (free 3D CAD) to check for clearance and mounting problems and to give me a 2D cutting template to take to the scroll saw.

Not sure which motor yet. I'll have to see how the weight comes out. The original allowed for a 1 pound (!) power system and a 4-6 ounce MINI receiver (!). It came in at 43 oz AUW. I should be just a little more than half that with a Berg 4L, outrunner and lipo battery. The bones as they sit in the picture are 10 oz. I might need to stuff a full beer can in the fuselage to keep it from floating away.

Should be an interesting addition to my hangar. Maiden weekend after next with any luck.

Eric

[Eric_N57105]

Maidened Sparky a week ago. All up weight with Hacker A20-20L, Berg 4L, Phoenix-25 and TP 3S2100 is 28 oz. Running a 10x4.7, but I think it could use a lower KV motor that can swing a larger prop. I'm looking for something around 900 KV.

Using HS-55 servos. They look SO TINY inside that huge fuselage, but they seem to have plenty of torque to handle it. The control surfaces are pretty small, and the plane is not flown aggressively. I used Sullivan Golden Rods mostly because they are non-metallic. The fuse is long enough that I can string the antenna entirely within its length and I didn't want to have two metal pushrods wires roughly the same length as the antenna that might set up weird resonances.

It's a very stately flyer. I haven't tried any aerobatics other than an inside loop which was rather ugly. That might change with the new motor.

No matter. When the sun lights it up through all that transparent yellow Ultracote, it makes my day.

Eric

[Sky Sharkster]

Hi Eric, great job on the Sparky! Man, that's fine workmanship, the nose looks perfectly formed and the way the shadow on the ground shows the tinted color is awesome. A beautiful bunch of "sticks"!
They do fly great, don't they?
Ron

[Eric_N57105]

Hi Eric, great job on the Sparky! Man, that's fine workmanship, the nose looks perfectly formed and the way the shadow on the ground shows the tinted color is awesome. A beautiful bunch of "sticks"!
They do fly great, don't they?
Ron

The 64" Sparky has a "floor" at the midline in the nose which keeps everything in alignment. Before it is installed, the nose looks like an old tennis shoe. Well, not quite, but any variation in stiffness in the stringers causes it to distort. One the 3/16" floor is installed, it holds everything in place.

I don't believe the original 32" rubber model had it. At least the ones I've seen at the SCAMPS field nearby don't. You would have to carefully select the stringers to make sure they were equally springy, I would think.

Another potential problem area is the LOOOONG skinny fuselage. I had to build up a jig with foam core formers to hold everything in alignment for gluing. As usual everything stiffens up nicely once you get the covering on.

It's a great looking plane in the sky and flies very nice. I had to relearn depth perception flying it, though. It's so big I keep thinking it's closer than it really is. I hit a huge light pole with the wing as a result. The wing hit, Sparky rotated 360 degrees around the pole and took off in the same direction without missing a beat. I landed to assess the damage, but there wasn't any. Not even a scratch. One again, my admiration for stick and tissue construction goes up.

Eric

[SaucerGuy]

You guys did some excellent work, I think I've been hanging out in the wrong forums seeing we actually have stick builders here.

I agree Eric, too many people think the balsa creations are too weak and you show through experience that it clearly is not as fragile as most people perceive, especially if you are beefing it up to handle the e-flight gear.

Again, good job people!

[Dereck]

Hi Eric
That's a beauty!

No sweat on the fuselage strength - if it can take a rubber motor, hanging an electric on the front is hardly going to be noticed!

Building a straight fuselage was a real test of skill - I don't recall anyone using jigs way back when (mostly on account of they cost money that could be better used elsewhere!) It always amazes me that they didn't use diagonals or geodetics more in this sort of model - that sort of thing is hardly heavy or rocket science and would have made life a lot easier.

If anyone else fancies something like this, there's a great article on fuselage jigs in last month's Flying Models magazine. It's aimed at smaller scale indoor models, but would adapt to something like this.

Can see that Senator of mine flying after this winter!

Hoping you enjoy your Sparky for a long while

D

[ZL3VML]

Hey Eric - well done, that is a great looking Sparky you have there.

Mine is still flying well - but it has nearly no glide, Too much propellor I think.

However as long as I keepjust a 'tad' throttle on it it will float around as if it was filled with Helium!

Hmm - would a folding carved Balsa prop perhaps be the answer?

I have heaps of fun with it anyway and I am sure yours wil be even better Eric.

Mark

[SaucerGuy]

Hey Eric - well done, that is a great looking Sparky you have there.

Mine is still flying well - but it has nearly no glide, Too much propellor I think.

However as long as I keepjust a 'tad' throttle on it it will float around as if it was filled with Helium!

Hmm - would a folding carved Balsa prop perhaps be the answer?

I have heaps of fun with it anyway and I am sure yours wil be even better Eric.

Mark

I'm intriged old man, you are a true old timer, I have much to learn from you !!!

[stinkweed007]

Now I know why I can only fly Foam... Thats some intense and awesome balsa work there..

LOOKS GREAT!!!

[SaucerGuy]

I pulled down my SE5 several times this week to do some work on it, I'm making it up as I go along conversion to e-flight wise, needless to say, I had only a few hours of actual work on it, the rest of the time was trying to figure out the game plan for the next few steps and prep for it. Foam is so much easier to work with, I'm going to tinker with it more soon enough "have a few 4X8 sheets ready for exploitation right on hand, just have one more stick build already blown up plans from yet another Guillows kit to build at the same time but I gotta get the SE5 out of the way first. Stay tuned for details along everything kiddies !!!.

[Eric_N57105]

Hey Eric - well done, that is a great looking Sparky you have there.

Mine is still flying well - but it has nearly no glide, Too much propellor I think.

However as long as I keepjust a 'tad' throttle on it it will float around as if it was filled with Helium!

Hmm - would a folding carved Balsa prop perhaps be the answer?

I have heaps of fun with it anyway and I am sure yours wil be even better Eric.

Mark

I was surprised by the same thing, Mark. My 2X Sparky is definitely not a floater. It has a relatively steep glide path given its free flight roots. But it flies on very little power as you mentioned.

What's really fun is to watch the tail as it lands. With a flying tail, the skid is off the ground with any forward speed at all. In fact, it will lift in a brisk wind before the plane starts rolling.

It's fun to fly and the best part is just watching it cruise around at half throttle or less on a partly cloudy day. Visually, it's hard to beat.


Eric