Eindecker,

I found myself in the same situation and posted the same question about a month ago. I live in the Chicago area and thought it possible to buy anything. I tried specialty wood companies, lumber yards and the super home supply mega-stores. No luck. I received two thumbs up on the use of carefully selected pine. One was a kit manufacturer. Pine if used, must be knot free and have straight grain. I went to Home Depot and they had a select grade of premium clear pine. It is sanded very smooth and is extremely hard for pine. There is not a knot to be found in an 8 foot board. If you find it, try to put a mark in it with your thumbnail. Then walk over to the construction grades and do the same. You should find your nail will mark the lesser grade much easier. This is in no way intended to be scientific proof or a comparison test done by engineers. It will only help you select a harder grade of pine. It is not expensive.

If you do want to use spruce, try www.aircraftspruce.com They sell spruce dimensionally cut to your needs. And, you can specify length. I placed an order only because the designer of the 40% 126" wingspan I am building calls for spruce for the fuselage longerons(almost 7 feet) and wing spars(over 6 feet). I contacted the designer and even he admitted the use of pine as a substitute would be okay, as long as the grain was straight and knot free. I look at the price of the Zenoah GT 80, Futaba PCM radio system and the little stuff that adds up to big $$$'s quickly and based my decision to use spruce on that factor. The designer agreed with my math. However, the designer implies no warranty should the spruce OR pine fail, but it is, I feel, better to go with was it known to work.

I have the pine here and ripped to dimensions, and, I REALLY want to start on this. In the back of my mind, there will always be the "Should I have waited for the specified material ?" question. I am now pacifying myself by cutting the rest of the formers.

Well, that's my two cents worth. But for the length of this reply, it's turned into two bits.

Base your selection of material on the cost of the finished aircraft, how long you intend to fly it and your time involved vs. the cost of spruce and pine. The pine, in most likelihood, will not fail, but....

Jim