Just to recap, a jig probably cannot withstand the stresses you will be putting the frame under when you build. If the jig could withstand these stresses, the tubing may not be able to do so. Either way, you may end up with a frame out of alignment. A bad thing all 'round. Thus most builders pin and tack, and then remove from the jig.
Its all good, thank you.
I have been tacking in my jig, then doing the rest of the brazing in a stand, but not pinning. Then I align it afterward on my alignment table. But I haven't been pinning, could pinning potentially help me on any way?
Pinning seems to be a newish fad (not a new technique). Been reading older books and they don't report a lot of pining or a lot a jigs. Both these seem to be modern crutches, not as modern as CNC MIG, however. Someone moving fast, but largely by hand wouldn't necesarilly want to pin if they could control the process without. It's more stuff to do. Some top builders today like to do it, as in the past. No one right way. Paternek does mention pining forks is worth doing, that the jig alone may not control the potential movement.
Bicycle Guide featured Richard Sachs in a June, 1990 cover article, "The Art of the Framebuilder." Richard discussed pinning and why he does it in the article. I have the seven page article as a 1.7 MB pdf file and would be happy to e-mail it to anyone that's interested. PM me with your e-mail address if you'd like a copy.
Last edited by Scooper; 12-16-08 at 06:21 PM.
Reason: Added cover image