Today is the day the Bridgeport and I became good friends, really good friends. As I said yesterday I’d completed the top tube miter on the head tube end. Today I started working on the top tube to seat tube miter. The formula that I mentioned yesterday was indeed correct. Basically the formula is this: subtract the head tube angle from the seat tube angle, then move the mitering jig the Bridgeport up that amount. Insert the tube “upside down” and ta-da. You’re done. If the universe was only fair. I did this, and one of two things happened. 1. I screwed up when adjusting the jig. Or 2, the jig was off / incorrectly calibrated / the phase of the moon was wrong etc. Since the jig worked for Clifford and Daniel I suspect number one, but can’t discount that some force in the universe is out to get me. We had similar problems getting the top tube to head tube miter angle correct yesterday, there was a bit of trial and error from the measurement the math gave us so who knows, maybe the thing was off a bit.. but anyway, I digress. I took a test cut near the end of my tube, smoothed off the burrs and gave it a test fit. I was off by a degree or so. I repeated this process a few times trying to compensate a little at a time and finally found the correct angle. It took fewer tries than the head tube miter, but still took a bit of futzing. After we found the right angle in the jig I cut my top tube with a hack saw and finished up the miter while Doug was out at dinner. When all was said and done the miter got done and the angles were correct. The tube was about 1mm too short (which is not a big deal by any stretch of the imagination, even for a princess like me) so we brought the front end in to compensate for it. Doug’s frame jig is really slick for this, two bolts and a small slide and we were all done. I took a look at the two other jigs in the shop to see what I’d have been in for to do this operation on them…. I’m glad to be using Doug’s jig in this case.
Today was also the first day of learning to braze. The morning started out with some instruction on using the torch, what knobs do what, how to control them and what we’re looking for in a flame. I’m still struggling with this. I know what the flame should look and sound like in the end, but struggle a bit in getting the torch to do that.
We started doing practice brazes of sleeves over tubes. Both of these seemed to go okay, I felt much better about the second. Doug made sure to let us all know we were doing okay and the instruction of Doug and Herbie (Doug’s assistant) was pretty good. It’s a ton of information to take in at once, and Doug’s in there trying to prevent you from learning bad habits right from the get go. The first braze was a bit stressful, the second went a bit better in the stress department and felt good in the process. Once cleaned up the second joint looked pretty good.
We then started to prepare scrap bottom brackets and tubes for more practice. I didn’t do anything with mine besides prepare it for brazing, the other guys I think both completed theirs (I was finishing up my top tube miters so Daniel could get his time in on the Bridgeport).
Tacked bottom seat tube to bottom bracket shell (not mine)
I did tack my bottom bracket shell to the seat tube (the real ones). I’d gone in early this morning to finish up the filing (it took about 20 min, sometimes you just need to take a brake and come back later). Doug came back out after dinner to do some stuff and walked me through the tacking and aligning process. Doug ended up saving my bacon when I got all tense with the torch and started to overheat the joint. I’m very thankful to have a teacher how can see a problem coming and react before it happens, rather than me muddling through this all on my own. I hope to get in some more practice with the torch tomorrow and will hopefully feel a little less jumpy and nervous with it. I’m sure its just a matter of time in the saddle.
All in all day three was good. Still lots more to learn. Still having fun. I’m really impressed with Doug as a teacher, he seems to be one step ahead and anticipating where a situation is going to go before it happens and gets out of control, this is huge when you have three folks out on the fringe of their knowledge who hope to end up with a decent bike in the end.
One thing I’m noticing is that its hard to find time to get other stuff done while I’m here. I’m supposed to be making time to get on my trainer and keep training for a race I have coming up soon as well as just keeping in shape. Hopefully tomorrow I’ll get my act together and remember to carve out some time.
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