Ron Smith wrote: > > Hi Steve, I have some experience in doing what you plan to do. Adding that > foam for what? Drag reduction? The cowling will end up lower than > the fuselage plane right? More weight not needed. IMHO. If you did > decide to do it, you need to have one layer of cloth laminated to the wood > structure to create the sandwich panel, then on top of that foam and I > would use boat cloth too reduce the weight.
Drag reduction and looks is all. No strength to be had and nothing needs to be contained down there. I'll probably just skip it and save the time, weight, cost, and trouble. > If you are not careful with the resin and foam the weight will bite you in > the butt. Yup, but bagging everything tends to get rid of the extra resin. It goes through the peel ply and into the breather. Pull everything apart and you have a surface ready for paint with nothing more than a wipe down with MEK. > The standard KR2 was 64 lbs at the boat stage with center spars and > fittings. Mine is 80 lbs. I have streched mine to 24", and 6" wider and 2" > taller. I'm starting to think that I'll only need 6" in front since I can move the engine forward a bit, but back is tough. Won't be any wider, maybe a hair taller, and around 25" long between wing and tail, but it's a KR1, so things are a bit different. > Make sure you use the method as described by Mark Langford, where you say > out the cloth on plastic sheeting, so you can add just the right > amount of resin to the lay up. That really saves weight. He has a very good technique there, best way to do it if you don't have a vacuum bagging setup. I'll be doing quite a bit that way, actually. The wings aren't easy to bag since they're hollow and would get squished. Now if I build foam core skins with kevlar on both sides it'll be different. > See my fuselage construction @ the link below. What are you using for the skin? Just glass (or similar) or is there foam in there somewhere? -- Steve 33...@swbell.net N3343V- '75 C150M N205FT- KR1 #6170 He who seeks will find, and he who knocks will be let in.
