First off, I am using Robart 615 since a buddy in our club is using them in his Cat without any problems. The retractable tailwheel is my creation. I manufactured it for my H9 P-47 and it turned out to be a tad too small. So I decided to use it for my cat which is the perfect size for it. The little gear doors on my mains are hinged but not hooked up to close with the main gear doors, yet. I guess I am going to use simply small rubber bands to do that. It does not take much to close them. Now, for the tailwheel am building split gear doors as well. It will be a little bid more tricky to close them in sequence with the tail wheel going in, but it's possible. I will post more pix once I am done. How far are you, big bird?

Hello, I just flew my CMP Hellcat for the first time today. I've had it for about 2 years and finally got it in the air. I've got a new YS FZ110 on it which runs great, TONS of power. Question is, can I put a 14 x 7 three blade on that engine/plan combination? I currently have a Master Air Screw 15 x 7 2 blade on it.

Try MA new 15x7 3-blade. The 14x7 3-blade is slightly too small, and the MA 15x7 2-blade is definitely too small for the YS 110. Even my YS 91AC swings an MA 15x8 @ 9600 rpm. Do you have a tach? Better to be safe than over-revving.

Thanks. You're correct. The 15 x 7 2 blade that's on there now exceeds the recommended rpms at full throttle but I have'nt flew at full throttle yet. I'm glad you verified that for me. I'll get the bigger props right away.

P.S. Do you know where I can get a replacement cowl for that plane?

Thanks for the information of the Retracts. What Struts are you using? Thanks

Ben

I've got a long ways to go, I have my retracts are installed and the wing epoxied together and am currently working on getting the horizontal stab on so I can figure out where to put my air tank. The Siearra air tank is pretty long and having the cockpit kit, it will have to go behind the wing saddle in the fuse.

Nobody commented my post about the incompatibility of epoxy and polyester resin (which my source says the fuse fiberglassing is done with), You apparently don't get a long lasting bond using epoxy to polyester. I'm totally in the dark on this but if true would have a big impact on the mounting of the horizontal stab. I would hate to have to go buy the polyester resin and hardener when I only need a half ounce of resin. Anyone have any thoughts on this?

bigbird

Bigbird, I used 30 minute epoxy on mine for this and it has held just fine for well over 200 flights. I am building a new one ( with all the Luke mods) and used it again without hesitation the only thing is to make sure and sand the paint off down to bare glass. Also anything that you do to the inside of the fuse sand first where you are gluing. I use 80 grit paper to do this. If you don't scuff up the glass it will not stick for very long.

Randy

Hot Rod,

I'm going to use the same paints that you used. I a bit of a novice at detailing so here's a couple of dumb questions...
1. How do you prep the surpace of this Hellcat before you paint it? Do you simply light sand it and paint over the original finish?
2. Are you using spray paint from a can or a spray gun?
3. Can I apply the Minwax Poly from a spray can?

I roger that, big bird. This plane is takeing me forever, too. But I am almost done with the interior. Should be able to paint by this week end. I've got the wing painted but used the wrong blue. Now I need to sand it off some. Buddy of mine has a ton of exactly mixed blues and white for Navy warbirds. He said I can have some for my cat. Best part of this bird is my CG is right on the money without adding any lead to the nose. For the "flyfisher", I have the Robart struds mounted on my 615's. Bigbird, my CMP-Hellcat's fuse and cowl is all epoxy fiberglass, not polyester. If it doesn't have a strong odor, it is epoxy. Polyeste also has a typical pinkish shade to it. "warks62" is correct, you should rough up any surface before using 30min. epoxy.

I'll have to look when I go out to the shop this morning but I don't believe it has a pinkish shade. It does smell quite strong when cutting with a dremel though not when it's just sitting there. Is yours a knockoff or a real CMP? Mine is the knockoff.

I believe I'm going to use the rudder and throttle servo positions to have dual servos for the elevator. I'll use 4-40 nyrod with a good S bend in them to take up any slack. This should go a long ways toward eliminating flutter.

thevirginian, Have you installed your air tank yet?

bigbird

Hey, bigbird;
Here is a picture of my air tank install. My Cat is a CMP not a knock off. I bought mine from AKModels and Alex convinced me that the CMP version is worth the extra money. But even though yours being the knock off, I don't believe the would have used polyester instead of epoxy. The reason for my assumption is simply, you have to be extremly quick to lay up the glass work in such a confined space like a fuselage mold. Polyester is normally used for boat hulls and the glass/polyester resin sprayed in. Polyester sets very fast. You have to work quickly and with no interruptions. That doesn't work for small, delicate jobs like a fuselage. So I believe you still have a regular epoxy/fiberglass fuse, like we all have. Just rough up the areas where you wnat to glue and use 30 min epoxy for your glue joints.

Finally! I THINK I have my clone hellcat done ...here are the basics

mcculloch 25cc conversion ..using the flywheel and magneto ...

robart retracts and struts ...I hope they are gonna holdup I think I have 615's

no scaling it out, no decals or weathering until I get a few flights on it.

elevator servos in the back to balance gas motor.

tail wheel moved forward to more scale position.

But best of all..if my fish scale is correct I am around 12.5 pounds for the overall weight !

Having the weight that low will help as this is my first plane with retracts. I have flown for 17 years off and on, but never pulled the gear up until now...or had an airplane with flaps...

Unfortunately this time of the year is REAL iffy getting good flying weather and I probably won't do a test flight on anything other than a decent day....

one of the nicest things about this kit is how well it hides a 25 cc gas motor inside the cowl, I wish some nice videos were online of this model...I posted one from france on this board. It was rather dark though, and left me wanting to see more..

Dion,
Are you still around? Do you still sell custom parts for the CMP Hellcat?

That could be support for the polyester theory, they must do something to make these things so cheap! I did look this morning and there is no pinkish cast to the resin. You aren't doing the custom cockpit I see, the sierra air tank is at least as big as Robarts and won't fit anywhere up front with the custom cockpit in. Luckily it weighs practically nothing cause it has to go behind the wing saddle in the fuse.

I like your cowl, how did you do the vanes in the "smile"

I sure don't see any difference, from your pictures, in the construction between the knockoff and the real thing.

bigbird,
According to Alex from AKModels Iwas told that the difference between the "cheap" knock-odd and the genuine CMP version is in quality of the kit. Since I bought the CMP version I cannot tell you what the actual differences are. I only know that the CMP kit is not bad at all for $200.00 compared to H9 or GP. The scale vanes in the smile are made of balsa wood and glued in with 30 min epoxy.

Hi Randy,

I'm getting ready to do the horizontal stab so I installed the wing and leveled it by measuring out from the fuse on both sides and found the center on both leading and trailing edges. I then measured up from the table at those spots. OK, wing level. I put the horizontal stab on and aligned it with the formed fiberglass, measured out from the fuse and measured up from the table. If you look at the view from the rear it matches the wing pretty well.

My problem is that the horizontal stab has (If I understand this correctly) negative incidence. The leading edge is 1/8" higher. If I give it positive incidence it will be out of whack with the pre formed part of the fuse.

Have you or anyone run into this or even checked? I'm leaning towards just putting them on like that...

Any opinions?

bigbird

bigbird;
All I can tell you is that the Hellcat one of our clubmembers is flying flies great. He bought it already built and its previous owner was certainly no building genius if you look at the plane. I would clue the stabs on where the are meant to go and not worry about it. That's what I did.

That FPE looks like a great match with the cowl. Do you have any pictures with the cowl off and where you have the ignition module installed? Thanks for all the information about how you did the panel lines. BTW I'm still playing catch up here but did you strip and glass the wings? did you post pictures of the process. If so please just point me back tot he post.

Thanks again

Ben

I guess your right, I tend to worry about things I probably shouldn't. It probably comes from my lack of experience.

Thanks

bigbird

CMP HELLCAT-Servo suggestions anyone? I am looking at using futaba 3001's for every thing but the throttle.Will they have the guts to tame a hellcat.Also any info on gas engines.I'm thinking of a weedeater conversion around 25cc.This is my first post here at rcu,and I am totaly amazed at what some of you guys are doing.To all of you I wish clear skies,the sun at your back and gear down landings.Keep this thing going.My hats off to Alex @ AK a fair price on shipping and way fast service,and a classic example of the AMERICAN WAY of doing business.War birds rule !

Hey, flyfisher;
I am in the painting stage, right now. No installed motor at this moment. But I will post new pics once I am done painting. Yes, I did glass the wings and all control surfaces. I think I posted one picture of the finisched wing, but can't remember what page it was.
raptureboy, I would go with 9001 servos. They are only ten bucks more but give you more power. A converted 25cc weedeater may be too much nose weight. Go with either a Zenoah 20, or an SPE 26 from Brillelli or BCMA-Engines. I posted it before how nice a guy Alex from AKModels is. That's where I got my Cat from.

Thanks virginian, for the help on the servo and engine ? I have a bunch of 3001's fresh on hand and I thought about using them on 6v to gain the extra torque.Any thoughts on that would be a help.

raptureboy,
The 9001 is not a bad servo, per say. If you have them on hand you might as well go and use them. I thought you wanted to know what servo to use before you buy new ones. I always go with a little stronger than recommended servo.

Virginian,
The work you have done has inspired me. Stopped by the local library yesterday and found a book on the f6f that has a seies of wonderful drawings and color plates of the Hellcat. The research to building and bashing ths bird is going to be almost as much fun as flying her. I look forward to your next set of photos.

Ben

flyfisher,
be patient, pictures will be coming soon