Looking for reactions of any type. I’m interested in clamp/flange couplers CNC’d from 17-4 stainless. In my case they would be used like S&S couplers or Z-couplers commonly are; one on the top tube and one on the down tube near the seat tube. Shown is Ritchey 31.8mm (1-1/4”) clamp, an envisioned 1-1/4” version (least cost design) and flange, and a 1” version and flange. The tube OD at the bottom is 1” as reference. The flanges have an anti-twist wavy surface, which is my own design. These were rendered in FreeCad. The flange design could be butt-weld, internal or internal braze, whatever.
What’s the value proposition?
Custom sizes.
Cost. Using Xometry’s oversees CNC option as a basis, the unit cost for as little as 5 couplers is $210, which is cost competitive. The unit cost for 25 couplers is $80. At 25 couplers it becomes cost effective to mimic the Ritchey shape, which looks pretty nice.
High Volume. Amendable to lost wax casting and Metal Injection Molding (the later followed by debinding/sintering).
I was under the impression that a compression coupler probably does not need any kind of "teeth"or “wavy surface”. These probably could be CNC machined with all 30 degree mating surfaces. The clamps are probably the more difficult pieces . . . ?
It would be nice to have an affordable alternative to the Santana or S & S couplers. Not sure how you would deal with Liability Insurance and who would be qualified to install these things ?
I don’t disagree a wavy or toothed surface for the flange is not needed, just being conservative. What I really like, even with the wavy surface, is that the clamp and flange are amendable to metal casting or MIM (metal injection molding) as mentioned, which Z coupler and S&S are not. I bought a Ritchey clamp to see it up close and the two halves were indeed cast. It cost just $35 direct from Ritchey.
Any reason liability or qualified installers is unique here, any more than S&S for Z couplers? Or for that matter 3D printed yokes.
