Dear Greg, I see that several people have offered replies to your quest for wood info. They are all good, but Ron Freiberger and Roger Mitchell are the closest to technical reasons for why most of us builders buy from reputable dealers such as Aircraft Spruce & Specialties and/or Wicks Aircraft Supply. While, as Roger Mitchell accurately reports, there are many possible woods to choose from, doing so reduces our chances of a safe and reliable end project. FAA has a book EA-AC43.13 which describes those things about wood that make it desirable for aviation use. To begin with, the lumber industry has carefully plotted how to get the maximum number of 2x4s and 2x6s from a given tree. This is great for the home builder, but tragic for aviation. The book shows an entirely different way to cut the tree for maximum strength. This jacks the price of the wood we buy, but it is much better and stronger because the wood is cut according to grain direction and strength, not the max 2x4s that you can get from it. Next, once we have properly sawn tree trunks, we have to dry the wood. There are two kinds of moisture in a piece of wood. First is the moisture between the fibers of the wood, and next is the moisture found within each fiber cell. Most ordinary lumber fails to dry both kinds of moisture, leaving us with wood that is heavier, less dense, and weaker. This means that if we buy ordinary lumber from Home Depot (not to pick on Home Depot), it is substandard for aviation use in probably three ways (often four ways). I am sorry, but that is MORE than enough to end any possibility that I will include any of that wood in my airplane. While we are all free to follow our own mind, heart and pocket book, I will fervently hope that you will eventually decide to be moved by the same logic that directs me. Wishing you many happy hours of building and many more of safe, happy flying,
Richard G. Alps PS. In direct reply to your letter, I would be reluctant to buy Spruce "locally." Again, that is because I would want to be certain that it was first CUT properly, and second, that it was dried properly. The very TERM "locally" suggests that it is not aircraft grade wood at all, but simply house grade wood that happens to be from a Spruce tree. Pretty scarey to me. All my best, RGA ----- Original Message ----- From: ggrabow...@lwtm.com To: kr...@mylist.net Sent: Tuesday, November 04, 2003 2:06 PM Subject: KR>Aircraft lumber Given the obvious safety implications of using the correct lumber for building an aircraft, I certainly understand the wisdom of using aircraft grade material. After reviewing several catalogs and magazines, it seems that spruce is the timber of choice. Unfortunately, spruce it not locally available in many areas, and shipping increases the cost considerably, particularly if it is not normally stocked. I am wondering if there are other timber choices that might be locally available, but without a significant decrease in safety over spruce such as poplar or white oak. I would appreciate any expertise anyone has on this subject. Thanks. Greg S. Grabowski ggrabow...@lwtm.com _______________________________________________ see KRnet list details at http://www.krnet.org/instructions.html
