Hello:

I am currently working on a Guillows Hellcat, and I have a couple of questions. I've redesigned the fuselage for 1-piece formers aligned with a horizontal keil. I'm using the design in the kit for the built-up tail feathers, and I plan on redesigning the wing to include a hardwood spar. I plan on sheeting the wing and fuse in 1/32" balsa.

1) I plan on using an AP .061. Does anyone have any experience running it inverted? Any problems or notes with fuel tank placement?

2) Any recomendations on thrust line or wing and stab incidences? I've heard to come to 0-0-0 with Guillows kits. Also any recommendations for the CG, I was thinking 30% MAC.

3) I plan on using silkspan to cover the entire model and painting it. I've never used it; will it be strong enough for a gasser?

4) What torque servos have you used on these sized Guillows conversions?

Thanks for your assistance! I will post pictures as they come along.

Thomas, take a look at this thread to get started:

http://www.rcuniverse.com/forum/m_3713170/tm.htm

As you pointed out in your post, the Guillows are good for the outlines and require a lot of re-engineering to reach r/c status. Search this forum, I think there are some other build threads for Guillows planes.

I'm sure others will post with more info.

David

Watch what you paint it with. The higher nitro fuels need proper butyrate dope or something exotic. And if you're using one of the exotics then they get heavy really fast.

I'm assuming that it's the 32 inch span Hellcat. There's still not a lot of wingarea on that puppy so watch your weight buildup carefully. I sure would not want to see the ready to fly weight get over about 18 oz tops or you'll find it's a snap rolling monster at the worst possible times. Add up the weights of all the radio components and engine plus fuel tank and any other fixed overhead weights. Subtract that from 18 and you'll have a target weight for the total airframe and covering. Tissue and dope will add about 1.5 oz roughly so deduct that as well.

Silkspan will certainly work for you but japanese tissue or even light art store tissue will work fine as well. On this size of model you're just trying to use the paper to act as a grain filler over the sheeting

If you're planning on adding a better spar plus sheeting to the wing I'd suggest you just scrap all the wing parts and go with a better airfoil than the simple flat bottomed one. Using a new airfoil will make it a lot easier and lighter to make the wing in the end.

Out of all the Guillows kits that have ever been sold it would be interesting to know how many ever get completed, especially for 1/2A RC? I built a FW 190, and it ended up weighing about a pound with 3 HS 55 servos. The throttle servo is a waste of time, waste of weight, waste of space, because these planes need to fly at full power to keep from falling out of the sky. The AP .061 will run just fine upside down, especially if you have the carb wired wide open. With one of these models, you don't have a lot of choices for tank height, just do a good job of padding it. The front wing dowel former makes cramming a tank and battery in a real treat, do this before covering. The keel pieces really hog a lot of space.

Everything should be set zero-zero-zero.

Brodak has a complete line of old school finishing and covering products [I would just get some drab iron on covering and call it good]. Good luck, not many completed and good flying Guillows kits have been reported here. It was kind of funny when one guy reported here that his RC conversion flys great, but won't loop from level flight and tends to spin in if it is forced to turn too quickly........

I did an RC conversion on the Guillows Zero in late 2005: [link=http://www.rcuniverse.com/forum/fb.asp?m=3713800]Guillows Zero RC Conversion[/link] It's stable and flies very well, as long as you keep the airspeed up and don't horse it around. Doing exotic maneuvers at below half-throttle, or giving sudden, full-deflection control inputs WILL cause it to snap & spin - Kinda like the full-scale WWII fighter planes... Senor Matthews offers good advice about the airfoil - converting to semi-symmetrical is slightly more work but will yield a much smoother flying plane.

I sheeted the wing and the fuse back to the trailing edge and ended up slightly on the heavy side. Strength-wise I don't think it needs it and next time (next time??) I'd only sheet the cowling area, the center section of the wing, and the underside of the fuselage around the wing (for landing strength). Over the years I've developed a love/hate relationship with silkspan. I love the way it covers and finishes but hate the way it punctures if you look at it the wrong way. My current fav is koverall, with the caveat that it's slightly heavier than other fabrics so you have to be careful not to glob on too much dope when finishing.

Hitec HB65s for the aileron / elevator, HS55s for the throttle. HS55s all around probably would have been fine, but the HS65s weigh nearly the same and have almost twice the torque.

Please do!!!

EG

Do you think the .061 will be enough, or do I need to go up to a .074 or .09? It looks small in there....

In the meantime, I framed up the tail assembly, awaiting finishing sanding, and built the keel for the formers. It serves no structural purpose other than to serve as a guide for aligning the formers. You can see a rough design for a former right below. This should reduce weight and free up a lot of space. The stringers and sheeting should provide the strength for the fuse.

I like Doculam for covering. Do a search for it over on RCgroups to find out all about it.

Im glad to see that Im not the only one making this venture. I bought a Guillows Vought F4U-4 Corsair not too long ago. I plan on converting it as well to rc. Havent made up my mind yet as to how Im going to power it.
This thead should be interesting to keep up with,cause Im looking for all kinds of ideas on how to ease this conversion.

I have a couple of questions about these guillows conversions.

Micro Servos- Are they all pretty much the same size? Ive got a couple that dont work,but was wondering if I can use them to get an idea of how much space to allow for them. Mostly on the wing area for Ailerons.

Also , I am sheeting the leading edge to the main spar with 1/32 sheet balsa,and am being very picky about seems showing through the covering. In these smaller models , is there anything that I can use to fill any seems or gaps with in the sheeting that wont add hardly any weight ?

Oh and I guess I have 3 questions. Has anyone tryed these guillows kits yet on a brushless setup?

tonywp, lightweight spackle works pretty good. It is probably lighter than balsa when bone dry.

hey thanks. this stuff works perfectly, and is as you said. its lighter than balsa when dry


tpallas , How is the build on the HellCat going BTW.

Not bad, things have been a little hectic, I'm in the process of transitioning from the Army to grad school. I cut out most of the formers and they fit quite well on the keel. From there I'll start on the innards. I'll post pics as soon as I can.

OK, here's the formers test fitted on the keel. So far not so bad. Once I have enough stringers in I can cut out the cross pieces to make room in the interior.

Sorry for the long absence, was on vacation. Did a little work on the Hellcat. I glued all the formers into place and began on the bottom stringers. Still debating on engine size - what do you guys think, .061 or .09? So far weight is nil. Sorry for the low quality pictures, but you can see the general progress (or lack thereof). All in all the project is much fun. I think there is a need out there for 1/2A's with more scale outlines and features - what do you guys think? For whatever reason I like the challenge of small, scale models.

I think an .09 would be way too big unless it really need weight forward for balance.

A .061 should be all you need. The .09 will be waaaaay heavy for your wing area.

EG

Looking good on the Guillows conversion! They look like a lot of work with all the stringers and such! I just did a B-29 job for a friend in TX where I used the Guillows plans, and cut it out of Blue Dow foam. He's going to use carbon fiber for reinforcement and is going electric as well. Good luck on you project![8D]