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Dwight's Framebuilding Tips.
- He built a headtube plug/heatsink that helps to avoid warping in the headtube when brazing it to two large frame tubes, which he has had trouble with in the past. It has tapered wedges so it holds firm but can be readily released to get it out even if there has been some slight warping or problems with thermal expansion and contraction.
- Also to reduce warping, he screws old cups into the bottom bracket threads. To prevent problems removing them after brazing, he lubes the threads with Permatex anti-seize compound, which is available in a formulation that resists breakdown up to 2000 F!
- One of his best purchases was a good 5 mm die that allows him to cut garden variety quick release skewers to any desired length (for seat clamps or whatever) and make cheap custom QR's.
- He installed the barrel of a micrometer onto a straight aluminum bar. Resting the bar on the faces of the BB shell he can check the alignment of the tubes after brazing.
- He recommends Sioux hole saws for cutting frame tube fish mouths. They are much cheaper from some sources than from others, though, so do a little comparison shopping and try for $6-9 apiece. Like any hole saw they wear out pretty quickly, but they cut well and at that price they are fairly disposable. Mark seconded this recommendation, but says he takes his own little jig with him to the store (accompanied by much rolling of eyes by the store staff, no doubt!) so he can buy just the ones that are most concentric and true, which is definitely not always the case.
Marks Comments; All holesaws cut a slightly oversized hole. A little touch-up at the base of the fishmouth with a half round file will get you a good fit. However when punching a head tube hole through a large monotube frame, you need an exact fit. So, I made a toolpost grinder for my lathe from an old die grinder. I chuck the holesaws in the lathe and grind them to size. I'm not sure Tim got the part right about holesaw prices. $6-$10 is the range I've seen for holesaws in general, but I've never seen the Souix (The best I've seen) for less than $9.
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