Machinists? Framebuilders? Seatpost insertion problem
Cross posting this, thinking maybe someone here has run into this problem on an older bike, or perhaps specifically on a UO-8.
OK I'll do my best to describe this. I am replacing the steel seatpost on my Peugeot UO-8 conversion with an alloy post. The seat tube is 25.4mm (so is the alloy post) but the original steel post is something like 22mm with a shim.
The problem is that there is a raised seam of metal on the inner diameter of the seat tube - like a "ridge" running down the back of the inside of the seat tube . (It's a cheap old bike and I'm assuming the tubing was rolled and then welded along this seam rather than the tube having been extruded or drawn.)
Anyways, with the original 22mm+shim setup, this seam of metal was a non-issue. But now that I'm trying to fit a 25.4mm post in a 25.4mm tube, this seam is creating interference, and I can't get the post in the seattube more than about an 1.25inches.
What, in your professional or non-professional opinion would be the best way to remove a raised seam of metal on the inner diameter of a 1inch tube? I would like at least 3 or 4 inches of seatpost insertion. My dremel can only reach about 1-1.5inches. Would a "pencil" extension/adapter for the dremel be the best plan? A round file?
Thanks for the help,