I forgot to ask if you will only be making a frame oR will you be making a frame and a fork? In your construction there will be diameter critical areas. BB, head tube, fork these may be difficult to acquire if you have very exact expectations. You may have to machine a significant amount from solid bar of 6 series eg 6082 T651 or 7 series eg 7075 T651. The 7 series has a higher tensile value and you could even design lighter sections. Then theres the issue of TIG/WIG welding. Wow welding is a heck a lot of fun but it takes a lot of time and skill to have the correct aesthetic appearnce (or ripples) in the weld seam. You also need correct settings to ensure good weld penetration and good preperation to ensure no weld impurities or pitting. Do try to use a certified aircraft welder for the sake of safety. Maybe somebody can test your welds. At least with a dye penetration test as a minimum. More advanced would be x-ray. Remember welding involves heat ( alot of heat) to melt the base material. So there is alot of expansion and contraction. Distortion is inevitable. therfore you have been well advised by Johan about a jig table to hold everything in place VERY securely to 'choke' distortion. This is costly but essential. You must invest in a strong bed and several versatile or adjustable and strong clamps. These must also be tube friendly at the same time. The appropriate filler wires should be in the area of a 5083 preferably and not 5356. Use this mindset as you proceed: I look at the picture of this beautiful bike that you posted and think: (1) if the head tube and the seat tube are not absolutely parallel, you will feel it. (2) if the BB is not perpendicular, you will feel it (3) if the seat clamp is not welded straight, it will p#ss u off....etc. No jig ...no go. So prep is the key to position, quality the key to safety.tarboy2009-08-28 15:59:25
