What is the rest of the story?Check with your sign-off authority before committing to laminated spars. I know of a Tiger Moth wing that failed pre-cover inspection because a spar had been laminated, even though it was in accordance with factory instructions for laminating a spar.
A Moth has eight wood spars in it, there was enough good wood available on hand to do seven solid spars and one built-up. The de Havilland instructions for lamination were engineered for just such an occasion and were followed to the letter. Inspector didn’t like that there was an odd one out at the pre-cover (the DH ‘STC’ for lack of a better term was presented to him) so while while three wing panels were covered right away the fourth was disassembled and a good blank for the eighth solid spar was sourced and machined before reassembly. I don’t know whatever happened to the laminated spar, it could have been sold to someone who could get it approved or maybe it was cut up to be used in other projects (rib cap strips and such) as often happens.What is the rest of the story?
Of course it will be weaker when cut to smaller sizes! The strength is proportional to the cross-sectional area. It will also depend on the grain orientation.Choosing wood has become a very challenging part of my build but I have found that if you follow proper grain run out and other regs. required it becomes much easier to achieve your mission. You can take a 2"x2" stick and may feel very strong at that size but when ripped to say 3/16"x 5/8" you can feel the strength just by hand pressure. I can't count the many pieces that were thrown into the burn pile after the feel of the piece was not to par in my view. I can't express enough how each and every stick of wood should be hand tested and meet your standards. How many builders have grabbed a stick from the pile that was ripped to size and went straight into the rib jig or fuselage sides without even being bowed by hand to see if a crack is heard or a splintering is seen to start ? Wood is such a beautiful type of construction to do and at times it's a shame to see so much not pass the needs for a aircraft build.
What do you mean by "lets go at 10.5 inches"? Do you mean your hands were 10.5 inches apart?Yes Aerowerx it really is a PAIN when you need a 12 inch piece and you fiddle with it and Snap it lets go at 10.5 inches. While building my tail group I had a assortment of different lengths that failed the stress test some got used and some kept my bottom warm near the fire
If the wood originally met the specifications then it should still be OK when ripped to smaller pieces.
So...... "look before you leap because he who hesitates is lost?"Keep in mind that wood is not uniform, obviously. You might have a board that is find in one area but not in another.
Although on occasion I look at the wood at the big box store, and think:"If I set my table saw at 47 degrees, rip that beam, and then square up the sides it would be a nice piece of Douglas Fir." But I would be throwing away 70% of it....It’s not the wood you walk by and say, that’s some pretty wood. At least I have never seen anything in the last 20 years.