The tubes are .125″ wall DOM (drawn over mandrel) tubing.
The mock-up made it this far before I realized the bevel drive was split down the middle, plus a few other small details, so it had to be made all over again.
Making the upper bevel drive covers has turned out to be difficult.
The flange is in the way for this side, so the milling head was angled 6.5 degrees to compensate. At this point I’ve worked on the Excelsior project slightly more than a year. They left the small sprocket on the right side, even though it wasn’t used with the bicycle cranks. Very complicated and almost impossible to duplicate, so regular shielded bearings were used. This is a rocker from the bottom of the front fork, to be cast in 4140, machined, then heat treated.
I bought an extra long centre drill, and extended the drill used for the holes. How those guys at West Cost Chopper can build an entire bike in 4 to 5 days is absolutely amazing. I made the pattern a little “chunkier” for added strength. The chips are small and curled; you can’t get that with a cheap steel. Bronze bushings (not shown) are machined up as spacers to position the side-to-side positioning of the cranks. Back To Top This is the pattern being made for the handlebar casting.
If this shape works well on the prototype, patterns will be made for future castings.