We use nothing new...we just do it ourselves.
Yes....the material just made me think...its the doing it "ourshelves" part that was my liability concern. I would like to build your plane spad3d...but I'm already thinking about "modifying" it....
Thats one of the most interesting parts of the SPAD thing...you can easily modify. Does that imply addition liability was my second thought...
Hmm, I just mark mine as "Experimental" on the wing...lol