Getting down tube shifter bosses square

[JLP]

Hi guys. Thanks for all the information here. Normally I lurk, and I love picking up what I can here.

I know this sounds silly, but I struggle to get down tube shifter bosses square. Does anyone have a jig trick or ideas on this. I'm eyeballing the flat part to be square with the bottom bracket, but my eyeball isn't so great.

Thanks in advance.

[e-RICHIE]

Hi guys. Thanks for all the information here. Normally I lurk, and I love picking up what I can here.

I know this sounds silly, but I struggle to get down tube shifter bosses square. Does anyone have a jig trick or ideas on this. I'm eyeballing the flat part to be square with the bottom bracket, but my eyeball isn't so great.

Thanks in advance.

It doesn't matter that much atmo. The levers or the parts that are added to them always have enough wiggle room such that nothing is really in plane once the bicycle is assembled. Otoh most braze-ons are already mitered so you can keep removing metal until you are happy with the results, visually.

[Eric Estlund]

Making stuff to make stuff with:

[JLP]

Thanks to both of you. I'm glad to hear that a little wiggle room is OK even with you guys. That said, I am SO copying that little jig! Thanks again. Joe

[Cooper Cycles]

I lightly score the centerline of the down tube with a square on a surface plate, then score another line with a tube block that is at the correct distance from the head tube. Braze one on then braze the next the same distance from the centerline. Sputnik also makes a nice little fixture for this purpose, but it seems a little overkill unless your really pumping out the frames with DT shifter bosses.

Good luck!
Travis Cooper
Cooper Cycles

[Andrew R Stewart]

Attachment 48282Setting up the lever bosses (or any relitively small braze on) to be in line with each other is not too hard. It's keeping them that way during the brazing. This is where a fixture is nice (to do both at the same time) or some type of holder that could do other braze ons too. While not what i made for lever bosses this holder works well for many needs. Andy.

[JLP]

Well, I finally got around to making this with a scrap of tubing. Thanks so much. That will help. Joe