I am looking for the best way to cut a home-made carbon fiber handle to get the cleanest, straightest edge to match up to a butt cap or other fitting. This carbon fiber handle will not go inside the adjacent fitting but instead will just butt right up to it. So the cut edge will be exposed and needs to be perfectly straight around the circumference. I am making the handles on my lathe. I am thinking that after the epoxy has cured and I have buffed the carbon fiber I will just use a sharp razor blade held very carefully as the handle spins and slowly apply the blade. Are there better ways? Do I cut it before or after applying the Perma Gloss? I want to make sure the carbon fiber edge does not start to unravel over time.

Thanks in advance for your help.

No, best not to try to cut it with a razor blade. Simply use a sharp parting tool or vertical scraper to cut the part square.

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Thank you. I will make an extra length to practice a few cuts on. Do you recommend I cut it before or after I apply the Perma Gloss?

If I was doing it, I would do it after the Perma Gloss.

In contrast to Mr. Kirkmans comment, I would use my 6 inch long razor knife.

But, either will work.

I'd but it first.

There was a similar post on this forum just a couple or three weeks ago with someone asking the same question. The parting tool/scraper was the ticket. It's made for this type thing. The carbon is too hard for most knives to do more than make a mess of things. But if you have an extra length available you can certainly test and find which method works best for you.

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As Tom states, a knife is not best on the carbon fiber, two reasons. 1.) Carbon is hard! 2.) A knife can wander while cutting.

Apply your finish so that the fibers are encapsulated and will not fray, then use a sharp parting tool at high speed.

Phil,
Copy that.

Of course any parting that I would be doing on such a grip would be with the grip spinning at 3600 rpm and then use the tool that would work best for the particular need.

I do this all the time and the tool I use is called a micro parting tool. I got it at Penn St. Industries. It is a little over a 1/16” in width and when sharp does a great job. I cut the handle after my two coats of epoxy but before I sand down and apply the finish. After you cut it you will get a few small fibers around the cut and you can use a razor knife to trim those off. I then take a black sharpie around the cut edge as you will sometimes get a little discoloration around the edge. Then I sand it down and finish.

Dick,
I looked at Penn State, but did not see any micro parting tools.
However, I did find this tool available from several suppliers. Is it the same one?

[www.discountcutlery.net]

The tool certainly looks like it is the perfect tool for the job.

Take care

No Roger that’s not it. I forgot that I had to buy a set. When I bought mine it was 3 tool set, now it’s a 5 pc set. $45 on the big "A."



Edited 2 time(s). Last edit at 06/16/2020 07:51AM by Tom Kirkman.

Dick, the micro parting tools I am finding look like small gouges (u-shaped blade). I am also seeing micro skews with a 45 degree angle. That seems more like what would work? Do you have a brand name I can search?

No mine is shaped like a regular parting tool just smaller. I found them on both Amazon as a set, and woodturnerscaralog.com as separate units.

I have a Robert Sorby parting tool that is 1/16" thick, works great on carbon fiber grips! Google it and you will find multiple sources.

Phil,
Are you speaking of this tool?

[www.amazon.com]

yes Roger that is the parting tool I use on carbon fiber. Cuts very cleanly!

Very similar to what I use.