Cutting carbon fiber handle bars?

tonyride

Don't piss off the red guy
I got an 800mm carbon fiber handle bar and that's just way too long for me and I need to get it down to around 740mm to match the bar I'm replacing (so about 30mm from each end). I know special care needs to be taken to cut carbon fiber so you don't end up damaging the bar and your lungs (I know carbon fiber dust is toxic). So has anyone here done this themselves or took it to a shop? If you did it yourself what tools and mask did you use? If you took it to a shop what shops in the central NJ area can do this? Thanks.
 

goldsbar

Well-Known Member
Hacksaw with a fine blade. Sandpaper cuts through carbon shockingly fast for touch up. You should also probably use some type of guide, though that's not mandatory.
 

stb222

Love Drunk
Jerk Squad
Hacksaw with a fine blade. Sandpaper cuts through carbon shockingly fast for touch up. You should also probably use some type of guide, though that's not mandatory.
This.

And it is such a small amount of dust, don't need a mask.
 

onetracker

Well-Known Member
Use the Park Tool fork steerer/hbar cutting guide. The fine tooth blade is essential. Use a standard respirator if you are really worried; you should own one anyway if you use spray paint with any regularity.
 
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Karate Monkey

Well-Known Member
Wrap the cut area in 4-5 turns of heavy masking tape. Helps reduce blow-through, and makes the cleanup of the cut easier. Make sure you sand down any loose splinters to keep them from propagating.

An abrasive blade works with less tearing. You can buy the super-expensive bike specific one, or just buy a carbide grit blade at the box store for cutting tile/glass.
 

tonyride

Don't piss off the red guy
Thanks for all the advice, even the one to trade. I don't have most of the tools needed to do it myself and the expense of getting them would probably be more than if I have a shop do it. I have a hacksaw but I'll need to get a finer blade. Given my hacking skills I know I'll need a cutting guide to keep it square. I have sandpaper and duct tape but no mask. I suppose I can hold my breath and do it outdoors but it's too cold outside. I can barely handle the temp in the garage. As for trading? It's a OneUp Components bar and it only comes in 1 length. The bar is for my bike park bike so I won't be riding it during the winter months so I suppose I can wait and try it and see if I can live with the 800mm bar while hammering down the trails. Bar end strikes against trees is what I'm worried about most.
 

Patrick

Overthinking the draft from the basement already
Staff member

SmooveP

Well-Known Member
Just did this. Used blue tape as a guide and a regular fine tooth hacksaw blade. Put the bar in a vise. Wrapped the bar with a rag and used the pipe jaws (below the the main flat jaws on most vises). Don't clamp too hard! Go slow with the hacksaw. Whole process took less than 5 minutes.
 

stb222

Love Drunk
Jerk Squad
should be under $10 for a hack saw blade for cast iron - i think that is the the type @Karate Monkey is talking about.
use a lock ring from a grip (or two rings) as a guide?

edit:
https://www.jensonusa.com/Park-Tool...fovDhKD6dbjhhd8vNHROcah1KO4vLXEhoCtzUQAvD_BwE

or like you said - play with it first.
--

i have sawzall version - i can mail one to you. probably 8" long - could use it to cut by hand. un-used, i got a pack to cut some pipe.
Actual footage of @Patrick working with his bar cutting machine.
yankee_workshop.jpg
 

Patrick

Overthinking the draft from the basement already
Staff member
Actual footage of @Patrick working with his bar cutting machine.
yankee_workshop.jpg

i have a planer. it is a very messy tool. - what i want is a jointer, for the once every 3 years i actually care the edges match.

was trying to figure out how to make a jig for no $$$. i've got some white (well, when new) grips that the ends are a mess, so the lock ring would work out great.

here is the blade on amazon $10 - will just assume everyone has a hacksaw frame.
https://www.amazon.com/Park-Tool-Carbon-Cutting-Blade/dp/B00426GT1W/

the guide is relatively expensive - https://www.amazon.com/Mighty-Saw-Guide/dp/B07BTH746Y/ - but might be worth having around.
 

stb222

Love Drunk
Jerk Squad
i have a planer. it is a very messy tool. - what i want is a jointer, for the once every 3 years i actually care the edges match.

was trying to figure out how to make a jig for no $$$. i've got some white (well, when new) grips that the ends are a mess, so the lock ring would work out great.

here is the blade on amazon $10 - will just assume everyone has a hacksaw frame.
https://www.amazon.com/Park-Tool-Carbon-Cutting-Blade/dp/B00426GT1W/

the guide is relatively expensive - https://www.amazon.com/Mighty-Saw-Guide/dp/B07BTH746Y/ - but might be worth having around.
giphy.gif
 

Magic

Formerly 1sh0t1b33r
Team MTBNJ Halter's
@Patrick I know a place you can visit once every 3 years with all the cool machines in North Plainfield. Let me know if you ever need to use something.
 

jklett

Well-Known Member
I've never cut carbon bike parts but I've cut 100's of carbon fishing rods and arrow shafts and I've always just wrapped some masking tape over where the cut will be then used an abrasive cutoff wheel for a Dremel. Comes out perfect whereas with a saw there was always tearing.
 
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