![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
(no subject)
Nov. 14th, 2017 11:07 pmMy coworker, the guy with the hillary-for-prison-2016 sticker, sigh, has a 1930 Model A. The shifter keeps coming apart, which makes an already interesting car more interesting. He doesn't mind so much as he can get it back together, but his daughter, in high school, likes driving it to school because nobody else can figure out how to shift it. Well, if the shifter's broken, she can't either. I volunteered to fix it.
Henry made a one-piece shifter. The way it's designed, the end that engages the baulk rings wears out quickly, and a market has sprung up in making reproduction ones. They make the end out of harder steel, but the handle out of softer steel for price concerns, and the two screw together, until the screw joint fails and it comes apart.
So I welded it together. This required removing most of the nickel plating at the end through anodic stripping, and the remainder by judicious application of a dremel sanding pad.
If that breaks, he has worse problems.
Inside the chunky tower is a big spring under a lot of compressive force. In an ideal world you press out roll pins in the baulk rings, slide them open, access roll pins in the linear shafts the baulk rings slide on, press them out, remove the shafts, then remove a c-clip around the base of the shift lever, at which point the spring shoots out and hits you right in the face. I decided that instead of doing that, I was just going to weld it very fast. With a TIG you can concentrate the heat where you want, so I put all the heat in the handle (as the joint didn't transmit heat well) and then would quickly bridge over to the heat-sensitive side and blast it for a fraction of a second, long enough to locally melt it, then spray the whole thing down with water, wait for it to cool, and do it again. It's a slow way to make a weld, but it means the shifter tower as a whole never got hot enough to be uncomfortable to the touch and even the bell that prevents grit from getting into the mechanism only got hot enough to steam mildly rather than actually boiling water that I sprayed on it.
Henry made a one-piece shifter. The way it's designed, the end that engages the baulk rings wears out quickly, and a market has sprung up in making reproduction ones. They make the end out of harder steel, but the handle out of softer steel for price concerns, and the two screw together, until the screw joint fails and it comes apart.
So I welded it together. This required removing most of the nickel plating at the end through anodic stripping, and the remainder by judicious application of a dremel sanding pad.
If that breaks, he has worse problems.
Inside the chunky tower is a big spring under a lot of compressive force. In an ideal world you press out roll pins in the baulk rings, slide them open, access roll pins in the linear shafts the baulk rings slide on, press them out, remove the shafts, then remove a c-clip around the base of the shift lever, at which point the spring shoots out and hits you right in the face. I decided that instead of doing that, I was just going to weld it very fast. With a TIG you can concentrate the heat where you want, so I put all the heat in the handle (as the joint didn't transmit heat well) and then would quickly bridge over to the heat-sensitive side and blast it for a fraction of a second, long enough to locally melt it, then spray the whole thing down with water, wait for it to cool, and do it again. It's a slow way to make a weld, but it means the shifter tower as a whole never got hot enough to be uncomfortable to the touch and even the bell that prevents grit from getting into the mechanism only got hot enough to steam mildly rather than actually boiling water that I sprayed on it.
