CRs:
There has been a lot of recent CR discussion about getting a clean cut when trimming a fork's steering tube down to size.
My method:
I first install an old steel headset cup and tape it into place (using duct tape) to mark where to cut. How to measure accurately is your business.
I then use a Dremel Tool cutting disk (instead of a hacksaw) and slice thru the steering tube. I use the "Cut-Off Wheel Number 409" (which is about 0.7 mm thick) with a special collet to secure it. I wind up the Dremel to about 8,000 RPM and just have at it.
It takes me a fair number of passes, going around the outside perimeter, and sometimes the disk breaks (wear your safety glasses) but I've always been able to remove the broken part of a disk from the freshly cut part of the fork, if it gets stuck there.
This method doesn't require a bench vise, which I haven't had at home. I brace the fork by wrapping it in a towel and putting it on top of a table, covered with some telephone books.
I then use both flat and half round files to square off the top and taper (de-burr) both the inside and outside top edges.
I've done two or three forks this way without problems. And I'm very, very fussy!
Andrew Gillis (Long Beach, CA)