Built Log - P-47 Thunderbolt (scratch foamy)

[TVCasualty]

I started building this one last year right before it started snowing. In the fading hours of the growing shorter days I worked through two motors, finally getting it to take off and fly straight only to realize a horrific mistake I shall not make again so soon... Each time I went out to test fly, it had a strong tendency to tip stall to the left immediately after it was released. This had to be one of two things, or so I thought, one the angle of launch was too steep. To which the plane was rebuilt (as it was wrecked after the first launch) Or two, the motor just couldn't cut it. I ordered another larger 500XTH from milehigh RC and stuck the little red T into the SE5a I made.
Then it took one last flight in 2007... It started off beautifully, a nice straight line gaining about 15 feet in altitude, when I started to correct for the slight left roll it was beginning to take... Well, as it rolled further and faster to the left I pushed harder and harder on the stick. The really sad part about all this was the fact that the plane did a very nice roll at about 15 feet without losing any altitude. Buy the time I had realized that the ailerons were reversed I was upside down, correcting for pitch (as the plane was not trimmed at this point) which then tuned into a dive from about 30 feet. Well nothing out dove the P-47 in WWII, except maybe the ground.
The only thing left was the tail feathers, a crumpled up fiberglassed nose, and the pilot with canopy.

Fast forward to this past weekend. Using googles sketchup I designed up a new fuse to be made out of FFF using a vacuum formed nose. Most of my time was spent leaning how to do surface modeling. The final result was by far the best I have built so far*

*As told by my wife


Some neat new things and a few lessons to be learned:

It is possible to vacuum form over plain old pink extruded polypropylene from home depot. Use petroleum jelly as a release agent and it will pull clean out.

Buy some nice rare earth magnets from someplace like "magnets for less." With something like 7 pounds of pull force you will be hard pressed to use glue that holds as strong (into foam) and will need to do something like tape over them to keep them attached before the glue lets them go.

For example when I was testing the prop rotation in my garage I had the wing attached by these magnets. It started to vibrate pretty badly, and I struggled to kill the throttle. Then the hot-glued seem let go, BEFORE THE MAGNETS!!, thus allowing the entire nose to tear from the plane! I was very lucky the nose went the other way as the prop sliced the wing up pretty good, right clean through the fiberglass, YIKES!

The entire nose is now held on by magnets, 6 pair, and the wing is held on my 5 pair.

Having a nice airbrush makes all mistakes fade away when making warbirds. If it looks rough, just dirty it up, makes it look as if it's been in service.

Onto the pics:

[TVCasualty]

And some maiden aerial shots, followed by the finished product.

Almost forgot the specs:

Wingspan: 45 1/2 inches
Weight: 36oz RTF
Motor: 500XTH (milehighrc)
Prop: GWS 1280EP (The 1170EP will drive it though)
Speed Controller: 40A from lightflightrc, thanks to Dave and Sarah
Power supply: Dewalt A123s in a 3S config

[Grasshopper]

Nice job TV!

[gfdengine204]

That is too cool! Very impressive work.

[TVCasualty]

Thanks guys!
If anybody wants more info on vacuum forming a really good reference this is the DIY:
www.instructables.com/id/Make-a-good,-cheap,-upgradeable-sheet-plastic-vacu/

It’s very simple to make, takes a small learning curve, and is very inexpensive. The results are excellent as well.
The two hardest parts are:
Obtaining PETG plastic, which can be an easy cheap solution IF there is a plastic supplier near you.
AND
Making the frame to hold the plastic before you put it in the oven.

The frame can have a lot of solutions, my final one, was to buy some stock flat bar and braze them together, which cost a little bit, but will work for a long time. I’m sure a wooden one would have been just fine. I do recommend something robust though.

Anyway check it out, and as I said I’ve been making my molds out of foam, so it really opens the doors wide as to what can be done from my garage (and kitchen) in a very short amount of time. Heat that PETG up to around 250-275 degrees, so it starts to sag, keep it off the oven rack, vac to on, and you are good to go -one cheap plastic part for your whatever.

[TVCasualty]

WOOT! Finally got some vid for this one!

YouTube Video

[TVCasualty]

If anyone is interested, I've got a new build log up of this one over on my webpage, you are welcome to come check it out, I managed to dig up some old pics of the original before i completely trashed it on maiden...

http://foamcasualty.com/blog_p47_1.shtml

Thanks again for all the great praise and support you guys have always given!

[Voyager2lcats]

TVCasualty, ah those were your pre-Sketchup days. Still, the P-47 looked very good- and you built it with that stiff and brittle pink foam! Boy did you have moxy.
Okay, now for the magic question: When are you going to build that P-40E? What's the wing going to be? 40"- 42"? Looked like you were going with an 11" prop (we're talking similar size to an E-Flite P-47; nice plane).

P.S. I'm downloading Sketchup7 at this moment.

[TVCasualty]

I just sent Dave from lightflight an email on the out of stock motor I want to use on my P40... Currently I have it sized for 50"!
Should be just like my corsair, but I've been putting it off as storage is becoming a concern over here... Don't want my wife to "accidentally" start ruining aircraft... In the mean time I've been a modeling fool, it's gonna be a good summer!

[Voyager2lcats]

I am really looking forward to your P-40 build. I do like your P-47 as well. That's a big boy! I promise to post pictures of the P-40 maiden flight (I am serious- it's just going to be a touch-and-go!).

Bob

[TVCasualty]

Lightflight is still out of the motor I would like to use on my P-40.
I'm almost ready to find a new supplyer.

In the mean time, I've been making another F6F, of my original design, only with a folded wing (instead of hotwire). I've been spending longer and longer on my planes, I think it's because it's so cold outside and I have to move parts of workshop inside to be productive. But this give me all the time I need to refine details. I can't wait to fly this one!

[Voyager2lcats]

Hmm, I was thinking it is taking a long time for your motor to come in. You might try BPhobbies (shipping is more, but they always have stock status of their material).
That is a NICE looking Hellcat. My compliments to the chef. I was looking at your Foam Casualty website yesterday- you have done a nice job with that (your graphics really set it off).

Originally Posted by TVCasualty

Lightflight is still out of the motor I would like to use on my P-40.
I'm almost ready to find a new supplyer.

In the mean time, I've been making another F6F, of my original design, only with a folded wing (instead of hotwire). I've been spending longer and longer on my planes, I think it's because it's so cold outside and I have to move parts of workshop inside to be productive. But this give me all the time I need to refine details. I can't wait to fly this one!

[TVCasualty]

So I looked into BP hobbies, and found they were out of the motor also, so I then turned to ebay...

This ended up being a mistake, as I got a great deal on the motor, $16 each for 3, but then got raped on shipping! (The "make an offer" said the shipping was $10, but the listing clearly states $10 +$8 for each additional item. OUCH! 24 to ship, AND they are comming from HK.)

So I've got some other issues to deal with but I really hope to get the wing cut and made for my P40 next week.

BUT I've got another special project going as well -pics to come very soon -hopefully!

[Voyager2lcats]

I am sorry to hear that about your motor(s). Headsuprc is a pretty good supplier if you want to check them out ($2.00 shipping on ALL orders), but then I am not shopping to power planes with 50" wingspans(!). Your planes are great and I am really looking forward to your P-40 build (off-topic!).

Originally Posted by TVCasualty

So I looked into BP hobbies, and found they were out of the motor also, so I then turned to ebay...

This ended up being a mistake, as I got a great deal on the motor, $16 each for 3, but then got raped on shipping! (The "make an offer" said the shipping was $10, but the listing clearly states $10 +$8 for each additional item. OUCH! 24 to ship, AND they are comming from HK.)

So I've got some other issues to deal with but I really hope to get the wing cut and made for my P40 next week.

BUT I've got another special project going as well -pics to come very soon -hopefully!

[TVCasualty]

Maidened my new Hellcat on Friday, I'm not disappointed, but more washout would have really helped on this model. I've got half a mind to scrap the wing and try it again, but I may just try surgery. It has a very nasty spin characteristic... The motor I was using worked very well, although I'm not sure of the amp draw yet, I fear it may be a tad high. Anyway the paint job looks really good, and it was a fun build. I hope to get some pics and vid up of it soon.

Thanks for your help Cat!

[Voyager2lcats]

TVC, you are very welcome. Washout is always something of a mystery to me. I have read it described as a twist in the wing or seen it appearing like a more concave curve on the bottom of the wingtip relative to the wing/airfoil as a whole. At least that's what I have seen on the E-Flite P-47. Please correct me if I am wrong. I will be looking forward to your pics and vid.

Originally Posted by TVCasualty

Maidened my new Hellcat on Friday, I'm not disappointed, but more washout would have really helped on this model. I've got half a mind to scrap the wing and try it again, but I may just try surgery. It has a very nasty spin characteristic... The motor I was using worked very well, although I'm not sure of the amp draw yet, I fear it may be a tad high. Anyway the paint job looks really good, and it was a fun build. I hope to get some pics and vid up of it soon.

Thanks for your help Cat!

[CHELLIE]

Very nice build, I dont know how i missed this thread your plane flies great, keep up the nice work, Chellie

[TVCasualty]

Thanks CHELLIE!