Do you still have this problem when you have the Diehl wing skins? Instead of foam and fiberglass, you have a prefab fiberglass shell over wood spars and foam ribs. almost everything else is wood. I had been thinking of a military motif which would have a lot of dark green. >From a new builder (half way there - bought it that way). Ray
--- Oscar Zuniga <taildr...@hotmail.com> wrote: > Netters; > > Mark Langford knows what he's doing. The critical > temp for extruded > polystyrene foam (blue Dow or pink Owens-Corning) is > about 165F, a > temperature that can be exceeded when a "KR of > color" sits out on the ramp > in the sun at your typical fly-in. However, > urethane foam (polyisocyanurate > or other) does not have this same critical > temperature at which it loses its > dimensional stability, and I believe Mark has used > urethane foam for the > majority of his construction. > > One of the main problems with polystyrene foam and > the temperature > limitation that indicates the use of predominately > white paint is that the > plane will develop a case of the "bulges", where > bumps and blisters, and > later sags and valleys, as well as ridges, develop > as the plane's structure > heats up into that temperature. These are the > things that can lead to > delamination of the fiberglass skins and also make > the plane look plumb > ugly. > > This is besides the thermal effects on the > structural airframe epoxy and the > fiberglass skin epoxy, both of which have their own > problems but not like > the polystyrene foam. > > What was it Virg always says, "build to the plans"? > If you don't know what > you're doing, paint it white and you'll be on the > safe side... > > Oscar Zuniga > San Antonio, TX > mailto: taildr...@hotmail.com > website at http://www.flysquirrel.net > > _________________________________________________________________ > Express yourself with MSN Messenger 6.0 -- download > now! > http://www.msnmessenger-download.com/tracking/reach_general > > > _______________________________________________ > see KRnet list details at http://www.krnet.org/instructions.html __________________________________ Do you Yahoo!? The New Yahoo! Shopping - with improved product search http://shopping.yahoo.com
