Scotsman
Posts: 79
Joined: 3/19/2004
From: Westford,
MA, USA
Status: offline
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Ron,
Sorry for the slow reply. Nicks instruction #73 is talking about the mounting tabs from the center section to the outer panels, but I didn't use Nick's system of plywood tabs to hold the outer wing panels on. I used a system described and suggested to me by Merlyn Graves. It is a 6-32 socket head cap screw that is around 1-1/2" long and goes diagonally through the root ribs from the outer wing panel into the inner panel/center section. Here is a picture of the outer panel root rib fit to the center section with hardwood blocks cut and sized for the diagonal screw.
There is not a ton of force pulling on the wing in that direction, so don't worry about the system being strong enough, it is plenty strong. The wood mount you see the screw going through is birch and there is a similarly shaped piece on the inside of the centersection root rib with a blind nut on the end for the screw to thread into. After the outer panel root rib is built up with the outer panel, I glued some filler balsa drilled for the screw head diameter to fill between the birch block and the inside of the sheeting. I glued it on before sheeting and shaped it to the airfoil when sanding the frame work during sheeting prep. Then you can sheet right over the top of it and drill out the sheeting by using a drill from the rib. It's a slick little system because it clamps the wings together in the end. makes for very nice fitting wing seams in the end. I never had to do the bondo trick on the ends of the ribs to get a good seam and the screw holds that seam nicely. Making the diagonal block is not that tricky either. I took a piece of birch block about 1/2" square and 1" long and cente drilled it for the #6-32 screw. I installed the blind nut and secured with some Hysol. Then I simply cut it in half on a 45 degree bias. With the block being 1" long and the ribs and rib doublers being 1/8" thick, the total length of all of that is a scootch over 1-1/2". It's a slick system and if you look closely in this picture you can see an oval hole in the bottom wing sheeting that is about in line with the wing joiner tube and that is all that you see in the end to hold the wings on. It is cleaner than Nick's design because you don't have a big rectangualr tab to fit into the outer wing panel.
Hope that helps. Give it a try, it is a lot easier than it may sound. One last picture. In this one you can see the oval hole in the centersection root rib that the diagonal bolt goes through and you cn also see the rectangle aft of the bottom spar that was filled in. That is where Nick's plywood tab would have been installed. If you already have yours installed, then you could very simply cut them off flush with the ribs.
One huge advantage of this system is that you can build and align the system working with just the root rib of the outer wing panel and the centersection and you will end up with the alignment of the outer panels dead nuts because the outer panel root rib is securly and repeatably held in place. You'll smile when you finish buiding the outer panel and slide it on joiner tube, tighten up that screw and the wing panels are very nicely aligned.....
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All Forums >> RC Airplanes >> RC Warbirds and Warplanes >> RE: P-38 Ziroli designed, built and aluminum plated by Metal-morphous 
RE: P-38 Ziroli designed, built and aluminum plated b... - 
Now let me see if I have this correct, the F-86, F-100, P-38, P-47 and now the P-51 all on the other side of the Rockies,,,, yup I am going to have to move just to stay in touch with those beauties!!! I cant wait to get this plane ready for our plating but I think this one is going to take some time to get right. Keep checking on the progress Ron and as soon as you and Joe are ready to fly your 
are they talking about the 1/4 tab on the centersection or is this something differant? If it is the centersection tab how does it attach to the wing? 
