[CR]Do-it-yourself guide to cutting a steering tube


Example: Framebuilders:Brian Baylis
From: <OROBOYZ@aol.com>
Date: Sat, 5 Jul 2003 19:58:42 EDT
To: jerrymoos@sbcglobal.net, classicrendezvous@bikelist.org
Subject: [CR]Do-it-yourself guide to cutting a steering tube

In a message dated 7/5/2003 10:49:10 AM Eastern Daylight Time, jerrymoos@sbcglobal.net writes:

<< Of course, one can take the crude approach and just attack the thing with a hacksaw, but I'm thinking many on the list may have some techniques and tricks to share for getting an even cut, avoiding damage to the steerer threads, and getting the length just right. Any suggestions would be appreciated. >>

Well, the most important starting point is that last comment you made.. i.e., getting the steerer cut to the correct length.

The safest approach is to completely assemble the head set in the frame and then mark the steerer tube with an indelible pen...You will have to carefully measure the cap nut. Also measure & write down all the needed dimensions, so you can double check yourself. Better to add a few mms and have to add a washer than end up too short (disaster!)

Once you are happy with the amount to be cut off, run the top adjustable cup all the way down past the cut area, as far down as it will go toward the fork crown. A junk headset part can be used but even the good one is fine if you are careful.. (Maybe it WOULD be best if this part is steel rather than aluminum.)

As far as the actual hack saw cutting goes, I do not think a guide tool is necessary at all. I prefer not to use one in CDO and we have a bunch of them.. Clamp the steerer horizontally in your vise (brass or plastic soft jaws are always a good idea.) Start the cut at your mark, remembering that the saw cut is the width of the blade so maybe be on the "high side" of your mark... Here are important tips: 1. Do not try to cut completely straight through the fork steerer in that position, but instead rotate the fork around after you have made perhaps about a 1/8th of the cut, this will mean rotating the fork a bunch of times but you have plenty of time, right? This will allow you to accurately follow your guides and not "drift" off and get an out of square cut... 2. Use the hack saw properly, i.e., do not use a seesaw, back and forth cutting action but cut only on the forward stroke. Try to not force it but let the nice sharp(!) saw blade do the cutting. Relax and soften up on the back stroke... It will make a difference.

Once the fork steerer is cut through, use a flat file to shape the end by filing at an approximately 45 degree and to the steerer. Do not remove a lot of material but enough to make a clean effect and transition into the threads. A medium to fine round file can be used to de-burr the interior. BTW, an actual de-burring tool is handy here and a nice cheap addition to your tool kit!

Once the end is cleaned up, the threaded race can be removed, it will clean the residual gorp out of the steerer threads as it comes off.

A final cleaning on the bench grinder with a fine wire brush installed will polish the threads and make the fork ready to be assembled.....

Dale Brown cycles de ORO, Inc. 1410 Mill Street Greensboro, North Carolina 27408 336-274-5959 fax 336-274-6360 <A HREF="http://www.cyclesdeoro.com">cyclesdeORO.com</A> <A HREF="http://www.classicrendezvous.com./main.htm">ClassicRendezvous.com</A>