At 03:38 PM 6/6/2005, you wrote: >If I buy strips of 4130 steel of the correct thickness from Aircraft >Spruce, can I use them as they are to make WAFs, or is there any treatment >(other that surface treatment) that I must apply?
You would get the steel in a Normalized (N) condition. After the milling process, the steel is raised to approximately 100 degrees F above its critical temperature and then allowed to cool in still air ( meaning slowly). The critical temperature is where the steel is no longer magnetic. It relieves the milling stresses and helps prevent subsequent failure. My generic reference manual, Marks' Standard Handbook For Mechanical Engineers, does not list 4130, but the typical temperature for carbon steel is 1500-1700 degrees F. Annealing temperature is typically lower by 100 to 500 degrees. If you can hold the steel in your bare hand while you are making your part(s), then the you have not caused any significant heat related change in the mechanical properties of the steel. If you do get it too hot to hold, then let it cool slowly in still air and it will be fine. Don Reid - donreid "at" peoplepc.com Bumpass, Va Visit my web sites at: AeroFoil, a 2-D Airfoil Design And Analysis Computer Program: http://aerofoilengineering.com KR2XL construction: http://aerofoilengineering.com/KR/KR2XL.htm Aviation Surplus: http://aerofoilengineering.com/PartsListing/Airparts.htm EAA Chapter 231: http://eaa231.org Ultralights: http://usua250.org VA EAA State Fly-in: http://vaeaa.org
