Cutting carbon steerer tube

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nrsnow
Posts: 269
Joined: Fri Aug 11, 2006 2:30 am

by nrsnow

Have you guys ever cut a carbon steerer tube? Do you just put it on a vise? Or bring it to a shop?

After you cut it, is it okay to use a starnut?
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by Weenie


kulivontot
Posts: 1170
Joined: Sun May 16, 2010 7:28 pm

by kulivontot

There's a special tool for it to prevent the carbon threads from fraying. Let a shop do it or Order the appropriate tool

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Martin.F
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by Martin.F

I cut mine with a 32tpi or more hacksaw. Tape where you are going to cut to prevent fraying and use a guide to make it straight. Never use a starnut in a carbon tube, you must use an expander of some sort.

system787
Posts: 138
Joined: Fri Mar 16, 2012 1:49 pm
Location: LA/OC, California

by system787

I use a tungsten carbide grit blades to cut carbon. It works well and doesn't fray, and the blades are relatively cheap.

Example: http://www.amazon.com/USA-Tungsten-Carb ... m_sbs_hi_3 (not the one i have but similar)

bricky21
Posts: 1405
Joined: Tue Sep 14, 2010 3:28 pm

by bricky21

I've cut lots of carbon steerer tubes. I use the finest tooth hacksaw blade I can find at the local hardware store, and I use a park tool saw guide to help keep the cut straight. It's not ok to use a starnut. Use a Compression plug which usually comes with the fork.

I know some people use electric chop saws, but I have not actually seen it done nor do I know what type of blade is used. :(

krzysiekmz
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by krzysiekmz

Orbea Oiz - xxxx
MSC Koncept Carbon Di2 - 6955g
Leichtkraft Team Carbon - 6868g.

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Sonny
Posts: 181
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Location: Hong Kong

by Sonny

If you cut the carbon tube by yourself -
- turn off the fan and close the windows around your cutting area.
- put some wet tissue under the cutting place of carbon tube to adsorb the carbon power.
- after cut the tube, use some wet tissue also to clean off the carbon power in/outside of the tube.
- finish !

Geoff
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Location: Canada

by Geoff

It is really no big deal, though I know it feels like it is.

Measure twice, cut once. Wrap the tube tightly with a bit of tape to prevent it from fraying. As others have advised, use the finest blade you can find. If it makes you feel better, you can use a cutting guide to ensure your cut I'd straight (you can also do it with a bench vise or freehand). Once you start to cut, use full strokes of the blade. Be careful, it will cut really fast. Only cut about halfway through, then complete the cut from the opposite side. Finish your cut with a fine file. I like to cut a very shallow bevel around the outside edge.

As others have noted, carbon dust is harmful to inhale. Do this outside if you can and wear a mask. If you push a rag down the steerer below where you will cut, then you will be able to pull it out after and you will not have carbon dust down the tube.

TheRookie
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by TheRookie

I cut A CF bash myself with a fine tooth jigsaw, used a dremel to deburr the surface, easy, no harder 9in fact easier) than ally.
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andrewh8877
Posts: 86
Joined: Mon Sep 14, 2009 8:51 pm

by andrewh8877

If it makes you feel better, you can use a cutting guide to ensure your cut I'd straight (you can also do it with a bench vise or freehand).

I made one from some headset spacers and duct tape, worked fine. You don't need anything fancy.

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devinci
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Location: Canada

by devinci

you can also use one or two old stem with a spacer on top (or not) as a cutting guide

Dont want to highjack, but I need to cut my alloy steerer. How do I make sure I push the starnut furter inside the steerer to avoid cutting it while making sure it is still sitting straight in the steerer tube?

Geoff
Posts: 5171
Joined: Sat Dec 13, 2003 2:25 am
Location: Canada

by Geoff

That's easy. Get a large dowel. Measure the depth of the starnut by placing the dowel into the steerer. From the outside, measure where you need to drop the starnut and mark your dowel. Knock the starnut down with the dowel. If the dowel is similar in diameter to the steerer, it will go down nice and straight. Cut away!

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devinci
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by devinci

thanks Geoff

by Weenie


02GF74
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by 02GF74

devinci wrote:Dont want to highjack, but I need to cut my alloy steerer.



you can use a pipe cutter on alloy steerer.

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