Ivy-T stem
This is the first stem that I’ve built. I did this one jigless, just counting on accurate miters to hold everything in place. That worked pretty well, except that my front clamp was about 1mm off center (fixed that with a file, but that made it slightly narrower than I wanted.
Some details:
- 1″ x 0.058″ extension (9cm long), 1.125″ x 0.058″ spacer, 1.125 x 0.051″ clamp. I’d prefer to have more material on the clamp in the future, and may buy some thick wall 1.25″ stock to turn down.
- roughly 95 degree angle (not measured precisely because it doesn’t really matter)
- roughly 9cm long (same reason)
- integrated cable hanger and spacers
- non-stainless bolts for strength
- the cable hanger fully pierces the top and bottom of the stem
double miter for the clamp and front
Checking the miters. Not done yet, there is too much of a gap under the handlebar clamp.
Brazed up. No burnt flux here!
I haven’t fillet brazed in quite a while, and was very happy with how these joints came out. They didn’t require too much cleanup.
“the cable hanger fully pierces the top and bottom of the stem”
Does this mean that on the stem extension tube, there are four small holes that the hanger wires were inserted into and then brazed in place?
Also:
“I did this one jigless….” “not measured precisely…”
Are you sure you aren”t Alex’’s evil twin? Doesn”t sound like the Alex I know.
Yes, there are 4 small holes. You can see the tiny rings of brass in the photo of the top of the steerer extension. I don”t feel like there is enough surface area if the hanger is just brazed under the extension.
I”ve been putting off building stems for a long time because I didn”t have time to build a jig first. I just wanted to get this one done, and Alistair pointed out that going jig-free would probably be fine since I can get very accurate miters on the milling machine.
I do measure things that matter (like tire clearance and frame alignment) very accurately, but I”m pretty fuzzy about some other stuff. For instance I don”t think I”ve ever measured the actual C-C seat tube distance on Gifford. It doesn”t really matter too much where the top tube intersected the seat tube, having accurate miters and something that looked right was more important than having exactly a 5 degree sloping top tube.
This is the photo where you can see the rings of brass:
http://alexandchristine.smugmug.com/Bicycles/Projects/Ivy-T-Stem/16013359_zpD7z#1201444613_ZScah-XL-LB
Given the lightweight theme of this build, I have to ask what the weight is? Some newer alloy stems are incredibly light but even if it’’s a tad heavier I like the integration of hanger, spacer and the fact that it’’s handmade from steel.