This has been discussed here and there on this forum but I thought I'd make an official post for discourse if anyone wants to get involved. Perhaps this can serve as somewhat of a progress report.
The point is to make a lower bearing cup that houses a 1.5" bearing and has a 44mm cup skirt that will fit into a head tube built to the Inset spec. This should allow us small builders to use tapered forks with a relatively low manufacturing cost output, using available tooling, materials and utilizing a (new) standard. (I'm going to go ahead and call it a standard now that King and Cane Creek are offering HSs using the 44mm I.D.)
For ti builders, a HT can be made using 1.5" Sched 40 seamless pipe. It requires about half an hour to an hour on the lathe to turn and bore the tube to a workable size. Steel builders should be able to source the same sized chromoly pipe. I admit that I'm a bit ignorant of steel alloys so you'll have to figure out the right stuff to use on your own.
One of the down sides with the seamless pipe is that the O.D. isn't quite big enough to fill out to the edge of the cup flange. The quickest way to deal with it is to skim off the edge of the flange on a lathe. I'm working with Mark @ Paragon to offer a weldable/brazable HT ring for those who don't want to skim the headset itself. I should be able to give him drawings next week.
Through a fortunate occurrence, I was just contacted by a huge local machine shop for a welding job, so I think I just found someone to make the parts. I'm probably going to run about 30 cups. I still don't have the price worked out but I'll certainly add an update here when I do.
I'm not really looking for input on the cups (though I won't ignore it) but if you guys want to have input on the size and shape of the HT rings, this seems like a great place to do it.
Sean
The point is to make a lower bearing cup that houses a 1.5" bearing and has a 44mm cup skirt that will fit into a head tube built to the Inset spec. This should allow us small builders to use tapered forks with a relatively low manufacturing cost output, using available tooling, materials and utilizing a (new) standard. (I'm going to go ahead and call it a standard now that King and Cane Creek are offering HSs using the 44mm I.D.)
For ti builders, a HT can be made using 1.5" Sched 40 seamless pipe. It requires about half an hour to an hour on the lathe to turn and bore the tube to a workable size. Steel builders should be able to source the same sized chromoly pipe. I admit that I'm a bit ignorant of steel alloys so you'll have to figure out the right stuff to use on your own.
One of the down sides with the seamless pipe is that the O.D. isn't quite big enough to fill out to the edge of the cup flange. The quickest way to deal with it is to skim off the edge of the flange on a lathe. I'm working with Mark @ Paragon to offer a weldable/brazable HT ring for those who don't want to skim the headset itself. I should be able to give him drawings next week.
Through a fortunate occurrence, I was just contacted by a huge local machine shop for a welding job, so I think I just found someone to make the parts. I'm probably going to run about 30 cups. I still don't have the price worked out but I'll certainly add an update here when I do.
I'm not really looking for input on the cups (though I won't ignore it) but if you guys want to have input on the size and shape of the HT rings, this seems like a great place to do it.
Sean