Cutting Carbon Fiber Handlebars and Seatposts
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Cutting Carbon Fiber Handlebars and Seatposts
I will be cutting (trimming) carbon fiber handlebars in the near future
I plan to use a hacksaw - have standard blades and also have a Park blade intended for carbon fiber
( also have a Park cutting guide )
Do you have a preference - standard blade vs blade for carbon fiber ?
Any personal size experience with the Park blade for carbon fiber ?
.
I plan to use a hacksaw - have standard blades and also have a Park blade intended for carbon fiber
( also have a Park cutting guide )
Do you have a preference - standard blade vs blade for carbon fiber ?
Any personal size experience with the Park blade for carbon fiber ?
.
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Generally the finer the blade's teeth the less likely the carbon will tear or split. An abrasive blade has a far finer "tooth count" (80 grit is 80 teeth per inch, as example) then a 32, 24 or 18 tpi blade has.
Having said that I have cut dozens of bars and steerers with a sharp 32 tpi blade using light pressures and fine sand paper (actually production cloth) action of the cut's face to both smoothen the face and round/de burr the edges with no issues yet known.
Good tools are nice but experience is a greater factor. Andy
Having said that I have cut dozens of bars and steerers with a sharp 32 tpi blade using light pressures and fine sand paper (actually production cloth) action of the cut's face to both smoothen the face and round/de burr the edges with no issues yet known.
Good tools are nice but experience is a greater factor. Andy
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Andy,
Would you wrap the bar with masking tape where the cut is being made?
John
Would you wrap the bar with masking tape where the cut is being made?
John
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I will be cutting (trimming) carbon fiber handlebars in the near future
I plan to use a hacksaw - have standard blades and also have a Park blade intended for carbon fiber
( also have a Park cutting guide )
Do you have a preference - standard blade vs blade for carbon fiber ?
Any personal size experience with the Park blade for carbon fiber ?
.
I plan to use a hacksaw - have standard blades and also have a Park blade intended for carbon fiber
( also have a Park cutting guide )
Do you have a preference - standard blade vs blade for carbon fiber ?
Any personal size experience with the Park blade for carbon fiber ?
.
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I have cut a few seat posts and cf steer tubes. I do wrap the cut area, not where the blade cuts, with tape. I also use a regular thin blade and cut slowly with little pressure, and keep checking the alignment and the cut through out the process. Sand to smooth the edges. The only guide I have used is hose clamps, but an actual guide might make it easier and keep the cut aligned. I have never had an actual failure doing this. Andrew R Stewart, IME, gives good advice.
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I also use a 32 TPI new hacksaw blade with light pressure (basically just the weight of the saw). I wrap the cut line with tape to prevent splintering and to make the marked cut line more visible. I have a cutting guide that works well but have used the edge of a radiator clamp as a guide in the past. The most important thing is to "measure twice and cut once".
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BTW lacking a saw guide one can use two radiator hose clamps to help control the sawing line. I also find that when sawing tubes or bars if I start the cut all the way around the stock, creating a shallow groove, the saw blade will follow the path of lesser resistance (or better said the saw will want to cut where the starting groove is). I haven't had to use either of these techniques on a carbon piece as I have various guides to use on steerers and such. Andy
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Thank you Andy.
I was wondering if the tape would help to prevent splintering.
John
I was wondering if the tape would help to prevent splintering.
John
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I've always had easy and clean results on carbon parts with a fine-tooth hacksaw, tape, and a hose clamp as an alignment guide. A quick rub with fine sandpaper eases the edges to finish the job.
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This is timely advice as I soon need to cut a 400 mm CF seat post for a new build with a vintage (i.e., 2000) frame that has a horizontal top tube.
Eric F Andrew R Stewart HillRider delbiker1 Just buy two of these?
Everbilt 1/2 - 1-1/4 in. Stainless Steel Hose Clamp 6712595 (homedepot.com)
Other than sanding to deburr the new end, do I need to add some epoxy to prevent splintering in the future? Or would I end up supergluing the seat post in the frame?
Eric F Andrew R Stewart HillRider delbiker1 Just buy two of these?
Everbilt 1/2 - 1-1/4 in. Stainless Steel Hose Clamp 6712595 (homedepot.com)
Other than sanding to deburr the new end, do I need to add some epoxy to prevent splintering in the future? Or would I end up supergluing the seat post in the frame?
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This is timely advice as I soon need to cut a 400 mm CF seat post for a new build with a vintage (i.e., 2000) frame that has a horizontal top tube.
Eric F Andrew R Stewart HillRider delbiker1 Just buy two of these?
Everbilt 1/2 - 1-1/4 in. Stainless Steel Hose Clamp 6712595 (homedepot.com)
Other than sanding to deburr the new end, do I need to add some epoxy to prevent splintering in the future? Or would I end up supergluing the seat post in the frame?
Eric F Andrew R Stewart HillRider delbiker1 Just buy two of these?
Everbilt 1/2 - 1-1/4 in. Stainless Steel Hose Clamp 6712595 (homedepot.com)
Other than sanding to deburr the new end, do I need to add some epoxy to prevent splintering in the future? Or would I end up supergluing the seat post in the frame?
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The end of a seat post is a pretty unstressed spot. Not at all what i would suspect the top of a steerer sees. I have painted the cut face of a carbon tube with both paint and epoxy. Can't say that either addition made any difference. Andy
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Thank you, this is an excellent and logical point.
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I've cut several CF steer tubes and handlebar ends and one seat post with just whatever hack saw I have on hand, and no guide. I put tape on the tube, mark a perfectly "square" circle (or several marks on the right line) around the tube where the cut needs to be, and carefully and slowly cut so that the cut follows the marked line. Nothing special except go slowly, adjust continually and dress the cut afterwards.That said, for cutting down a seat post it really doesn't need to be square at all. For steer tube and handlebar ends, it should be decently square, but exactly square is not necessary. If it is not good enough with careful free-hand sawing, you can square it off better with a file to get it within whatever personal tolerance and/or aesthetics you need.
Last edited by Camilo; 06-22-22 at 12:03 AM.