Sounds very similar to what AL did on the BBQB Bearcat.

Choose proper grain orientation, reinforce appropriately, should be fine. If needed, glue 1/16" - 1/8" upper/lower longer one to increase the glue surface for the molded blocks, and you should be fine.

Also, remember - tight joints to make it a monocoque structure (eggshell, not bomb casing).

Steve

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Should be plenty strong enough in general. The issue is that it gives you very little tolerance for sanding or misalignment.

    Brett

Should be plenty strong enough in general. The issue is that it gives you very little tolerance for sanding or misalignment.

    Brett

I will use the lost foam method to mold and cut the formers for the decks.  I used stringers on Endgame III turtle deck since it was 23" long.  Two years now and no sagging.  I am worried about sanding the fuselage joints so I will be adding soft 1/16" x 1/8" doublers on the inside top and bottom to make sure I can sand the curve.  Also makes mating the moldings a piece of cake.

I scrapped the 6lb 1/8" sides and remade them with 8lb 1/16.  They are 22grams lighter!  Thats 60+ grams I don't have to add to the nose to keep the CG. It all adds up.

Ken

I will use the lost foam method to mold and cut the formers for the decks.  I used stringers on Endgame III turtle deck since it was 23" long.  Two years now and no sagging.  I am worried about sanding the fuselage joints so I will be adding soft 1/16" x 1/8" doublers on the inside top and bottom to make sure I can sand the curve.

I scrapped the 6lb 1/8" sides and remade them with 8lb 1/16.  They are 22grams lighter!  Thats 60+ grams I don't have to add to the nose to keep the CG. It all adds up.

Ken

   I have been using 3/32 for a long time, but I went back to 1/8 on the last airplane because I have plenty of 4 lb wood, and the thickness makes it easier otherwise.

     Brett

I would also suggest an internal tripler around the wing opening to give yourself more "meat" for the wing to glue to.

Steve

If you make fuselage sides a little curved in fuselage cross section, that will increase the form stability a lot. L

I thought about that and even drew some formers but changed my mind.  I don't have any way of forming it without some form of jig.  You are absolutely right, curved surfaces would be better, just not do-able.

I got this idea from getting to see the inside of an aft fuselage from one of our better builders that happened to "land" spinner first at a very steep angle of attack under full power and literally exploded.  I got to thinking 8lb 1/16 is the same weight as 4lb 1/8 and I haven't seen anything lighter than 6lb in a decade.

Ken

TO Dave and Steve:

wing will have 1/4" internal and external fillets.  I use the old wingtip grip for the pull test.

Ken

Nicely done. I was thinking about that very thing, internal "Warren truss" framework on the fuselage sides.

Ken, if there's enough of us local, what do think of a group building session once a week? Can trade ideas and such. Building with friends is better than building alone.

Steve

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I would love to but I simply can't.  I am still working and the office is just too small.  It is a good idea though.

Ken

That truss method for stiffening the 1/16 fuselage sides works well enough.  I have been doing that for some time now with no issues.

What ever you do, be sure to warn your pit man just how thin the fuselage is.. I almost crushed Paul Walkers P47 one year as it was so very light and thin...

I noticed today just how how easy it would be to crush it if you think it is solid 1/8.  I am going to add a few cross bars once I have the pushrods in so I don't block them.  The frame is really solid and light.

Ken

Since my search for reasonably priced 1/16" plywood failed I am using equally expensive yet readily available .3 and .5mm carbon fiber sheet where I would use plywood.   What is the best glue for CF sheet, it is not pours like the CF tubes.  CA works well but I worry about it's brittle nature and what happens when things vibrate.  Does Epoxy have the same issues?  I have JB Weld.  It is the same color!  What say you?

Ken

Epoxy is best BUT secondary bonds are never as strong as the original material.  Back when I was designing boats for a living for Mark Twain Marine we had issues with motor mounts- set in to the hull later- cracking loose with engine torque.  We had to add in special shop instructions to grind the surfaces where the new bond was to be made before setting in the mounts.   Epoxies and other resins leave a slick surface and sometimes also mold release wax works it's way to the top.  Those carbon sheets may have some mold release imbedded.   Sand well and clean with alcohol and a soft rag before glue up.  Should be OK after that.

Dave