CEF speed contest Design Discussions

Starting to look like a Super Corsair. Well, pieces of a Super Corsair...


Jim

OVERLORD wrote:Great site, Jim. A few days ago, I looked at pictures of the Tsunami, also mentioned on this site.



Below the CL version: 1 picture, 2 birds



Lieven

That's a great plane Lieven. Are you planning on building it?

Jim

Sneak preview:

Hi Jim,

No not at the moment. I started building another one already. It'll be a racer as well. The main wood parts are cut. Just need to find the time to continue. I saw the pictures of your plane when I was writing this post. Looks real good, and this IS a Corsair indeed.

Lieven

JPvelo wrote:Sneak preview:

Looks fabulous Jim!!! I can understand your dilemma with scale-like gear now.

I'm trying to visualize a bell-crank/lead-out arrangement for that wing... Maybe a perpendicular 1/8" plywood bell-crank plate mounted in the fuse just above the wing's cathedral panel, with lead-out "eyelets" at the extreme wing-tip would work... without inducing stress on the angled wing-joint?

roddie wrote:

JPvelo wrote:Sneak preview:

Looks fabulous Jim!!! I can understand your dilemma with scale-like gear now.

I'm trying to visualize a bell-crank/lead-out arrangement for that wing... Maybe a perpendicular 1/8" plywood bell-crank plate mounted in the fuse just above the wing's cathedral panel, with lead-out "eyelets" at the extreme wing-tip would work... without inducing stress on the angled wing-joint?

That's the plan. The plane I'm doing had flat plate wing tips that extend past the actual wing all the way around.

I will make them of 1/32 ply and drill for lead out guides.

I thought about slotting the fuse for the bellcrank but ended up not. Replacing part of the thinner sheeting with ply was just too easy. On the super corsair I doubt you have any other choice that will work well.

I hope you have a plan for stiffeners in those joints. Maybe some plywood sawn into slots?

I need to weigh my model still.

Phil

pkrankow wrote:I thought about slotting the fuse for the bellcrank but ended up not.  Replacing part of the thinner sheeting with ply was just too easy.  On the super corsair I doubt you have any other choice that will work well.  

I hope you have a plan for stiffeners in those joints.  Maybe some plywood sawn into slots?

I need to weigh my model still.  

Phil

I am going to glass the bottom of the joints and the trailing edge as well.

Jim

I'd show a picture of mine, but a couple pieces of uncut sheet balsa doesn't look like much. 

I will say I am doing a Spitfire though.

Cribbs74 wrote:I'd show a picture of mine, but a couple pieces of uncut sheet balsa doesn't look like much. 

I will say I am doing a Spitfire though.

I'm keeping up with you Ron. 

I did cut thefuse for one plane last night. But I don't know if I'll use it for the contest. I'm going to build the RC Gee Bee that I liked so much also. For the contest, I might go with and P-40. I do like the Spitfire too. It is one of the best looking planes our British friends ever made. And it looks fast, which should help.  

duke.johnson wrote:

Cribbs74 wrote:I'd show a picture of mine, but a couple pieces of uncut sheet balsa doesn't look like much. 

I will say I am doing a Spitfire though.

I'm keeping up with you Ron. 

I did cut thefuse for one plane last night.  But I don't know if I'll use it for the contest.  I'm going to build the RC Gee Bee that I liked so much also.  For the contest, I might go with and P-40.  I do like the Spitfire too.  It is one of the best looking planes our British friends ever made.  And it looks fast, which should help.  

You could always do a Supermarine Spitefull, the spitfires baby brother:

My F8F-2 has a serious nose-heavy condition with the Babe-Bee  although it's a bit premature to make that determination without paint, push-rod, tailgear etc... I am glad I left myself a little room in the length... because it looks like I may go with a "horseshoe" back-plate. The cowl should be a better fit with a shorter engine too. I'll need to re-drill my firewall anyway... and then I can make the choice later on.

That's what makes this contest such a challenge...

roddie wrote:My F8F-2 has a serious nose-heavy condition with the Babe-Bee  although it's a bit premature to make that determination without paint, push-rod, tailgear etc... I am glad I left myself a little room in the length... because it looks like I may go with a "horseshoe" back-plate. The cowl should be a better fit with a shorter engine too. I'll need to re-drill my firewall anyway... and then I can make the choice later on.

That's what makes this contest such a challenge...

I'm crazy nose heavy too. Generous paint can make it tail heavy in a hurry.

Phil

pkrankow wrote:I think the elevator is getting Monokote as an expedient.

Phil

Actually, that'd be scale, too. Many of the WW II warbirds had metal covered wings/tail surfaces, with fabric covered elevators, rudders, and ailerons. You're just following suit...

The Suitable Mark

JPvelo wrote:You could always do a Supermarine Spitefull, the spitfires baby brother:

I've always liked the Spiteful better than the Spirfire.  Also designated as the Seafang.  Maybe it's because of my Navy heritage.

The Wet Feet Mark

batjac wrote:

pkrankow wrote:I think the elevator is getting Monokote as an expedient.

Phil

Actually, that'd be scale, too.   Many of the WW II warbirds had metal covered wings/tail surfaces, with fabric covered elevators, rudders, and ailerons.  You're just following suit...

The Suitable Mark

Well, yea, but I am modeling a modern crop duster that has metal control surfaces.

I do agree that many WWII era aircraft had fabric skinned control surfaces, a large number of prototypes and early versions on both sides of the war are reported this way.

Phil

(anyways I lost the elevator and might need to make a new one.)

[/quote]
Nice looking plane also.

pkrankow wrote:

roddie wrote:My F8F-2 has a serious nose-heavy condition with the Babe-Bee  although it's a bit premature to make that determination without paint, push-rod, tailgear etc... I am glad I left myself a little room in the length... because it looks like I may go with a "horseshoe" back-plate. The cowl should be a better fit with a shorter engine too. I'll need to re-drill my firewall anyway... and then I can make the choice later on.

That's what makes this contest such a challenge...

I'm crazy nose heavy too.  Generous paint can make it tail heavy in a hurry.

Phil

There's a couple of ways we can effectively deal with c/g issues even after the model is built and painted. Remember... "nose-heavy" will fly... and we're going in a straight-line. With models this size on 42' lines... we'll need to offset the drag of the control lines. Anyone building "super-light" is not going to meet their speed potential. If you designed for a 5cc "tanked" engine; you can switch to a "horse-shoe" style back-plate alone... which places the engine cylinder "back" 1/4" and an external "wedge" tank can be mounted further back too. Drill your firewall with both patterns, and you'll have a choice. If you're still nose-heavy, obtain or make a pair of lightweight wheels... (they only have to work once...) An .062" Music-wire push-rod weighs about 4-5 times that of a carbon fiber push-rod. Glue sm. steel washer(s) to your tail-wheel if you have to.

I started building as well. I cut fuselage, wings and stab.



I didn't know how to start cutting the slot for the wing 'cause I never built a profile fuse before. I think, in general you first drill a hole and then start cutting with a saw. In fact I should buy one of those machines. I ended up chiselling it out which worked rather well.



All fits together quite well.



Lieven

Looking really nice Lieven!

Very nice! I got a couple pictures up in the Traveling Prop thread, I'll repost the links here.

My building board staged with extra stuff I am working on. (flite streaks)





Oh, current weight as pictured 123g or 4.3 oz. Trim paint, elevator, fuel system and controls are needed.

Phil

Thanks. When I was sitting in my car at the traffic lights, I realized I forgot to mention what plane it was. It will be the 1936  Greve Trophy and Thompson trophy winner, the Caudron C460 "Rafale" s/nr 6909.  Vive la France!!





This plane crashed on 19 Dec. in the same year during a record speed attempt.

But there's more, and this also confirmed my choise, in 2008 or so, a Californian workshop decided to build a replica of the C460. So it's now sort of Franco-Américain.

https://www.youtube.com/watch?v=ekG_jy7RhiM&list=PLD7E2942CA91CA6FA

Lieven

Looks really fast. Are you going with the same paint scheme?