Yogi
Well-Known Member
I'm currently building a Fauvel AV 361. There are 64 nose ribs. I just weighed the wood it takes for a typical nose rib then cut a piece of 1"thick 2lb. foam to the same shape and weighed it. The foam,to my surprise,was 34% lighter. I think I will use foam for L.E. ribs in lieu of wood for all but those at tip,hinge and fuselage juncture. I have seen several designs that use this technique. Pros: easier fabrication,more horizontal support for D-tube skin so,NO VARNISHING( getting between gussets is a bugger ),no chance of rot, more gluing surface, and less weight. Cons:Need careful clamping during skin application,not as ding resistant?( no springback ) The extra glue required for the skins appears to be about the same as that required for the gussets and verticals of the wooden ribs. I built a Mitchell Wing in the 80's that used this same method. Any thoughts?