While I could have welded the parts together, I wasn\'t too keen on the finished shape and I suspect that it would have to be machined in the end anyway.
I milled mine from steel. It is made so that it laps over the top and inside of the rails and its contours please me at least. To join it to the rails I drilled the support and frame for a 1/8\" dowel and silver soldered it together using a kit made for joining Band Saw Blades. I also machined the support bearing bore larger to receive a bearing. I made three, two fitted with ball bearings and one with a roller bearing. Both seem to work equally and I ended up using twin ball bearings.
Two join the rails to the support, I placed the steel rails on a flat surface (actually the magnetic chuck on my grinder) and clamped the side rails together with a set of 1-2-3 blocks in between using c-clams and a bolt through the trunnion holes in the side rails. A third block was used to assure tha the support was in place correctly and square. I clamped the block to the end of the rail, aligned and clamped the suport to the block and then aligned and clamped the second side rail to the support. This made sure that the rails were level, parallel and not staggered to each with no twist and that the support was square to the rails. The front block can then be removed and the support fluxed and soldered in place. This is made easier by the kit which contains a tin silver solder foil which is cut and and placed between the parts in the joint.
That how I did mine, your mileage may vary.
nitewatchman
