JL07

On 10/31/2006 at 2:27 PM, EZ AHAB said:

I've been doing some research on the foam used in the flying surfaces of both the Long-EZ and the Cozy. What I've found is that the original "2 lb/ft^3 Styrofoam FB" called for in the plans doesn't seem to be made any longer. A/C Spruce still sells what they call 2 lb/ft^3 Styrofoam FB so maybe they stocked up on it? Wicks sells "POLYSTYRENE Blue Large Cell expanded 1.6 lb. density". I called both suppliers and the lady I talked to at A/C Spruce had no knowledge beyond what was printed in their catalogue. She gave me a phone number to their distributer which led to a dead end. Wicks sells 1.6 lb/ft^3 pipe insulation. I ordered samples from both suppliers and they are indeed different. The foam from A/C Spruce

is, in fact 2 lb/ft^3 and has a larger cell size than the stuff from Wicks. What concerns me is that the original Styrofoam FB had a compressive strength of 35 psi while 1.6 lb/ft^3 pipe insulation has only 20 psi. That's less then 60% of the strength. Also, there are warnings in the old canard pushers about using only the correct type of wing styrofoam called for in the plans. It specifically says not to use different types with less strength. There is also, by the way, a specific warning against using dock floatation foam which I have heard others say is the same stuff.

 

I would just order the stuff from A/C Spruce and be done with it but A/C Spruce is really expensive. The price difference between suppliers for foam for 1 airplane is $260. Add to that the fact that I would have to pay for shipping from A/C Spruce while I could go pick up the other stuff in my truck and you get probably more like $500 in price difference. Do any of you have any further insight/information on this? Perhaps a Cozy builder could find out since it is still a supported design.

Hi EZ Ahab,  

Since the Cozy Mark IV design plans only mentioned Wicks Aircraft and Aircraft Spruce, who did you end up ordering your foam from?  

Or, did you end up using floatation foam from your local dealer since you are able to bring your foam back home with your truck?