How to cut thick carbon fiber?

Other than a laser cutter, try sandwiching it between plywood and using a high carbon blade in a good jig saw. (What I used for Kevlar)

Have a look at the previous thread on the subject.

http://cr4.globalspec.com/thread/34968#newcomments

Yes, I've read that thread before to post mine.

That is more for carbon fibers cutting only, not epoxied carbon. The rest of the discussion is about moderate and sophisticated cutting, but that kind of cutting is out of the game for me. Unfortunately in the area that I live there isn't such equipment like laser, water jet, ultrasonic cut... everything is left on the hand tools... and if it does I do doubt that it'll worth to cut small piece on that machines. Total length of cut I need is about 6 foots, mainly straight cut and some routing.

Thanks anyway :)

Hello ModulusMK, Is the epoxied carbon fiber for cosmetic or structural?

I would think it would work like epoxied fiberglass. In automotive they use saws, grinders, and any other tools to cut and shape.

I would think with the epoxied carbon fiber the band saw should be ok.

If the carbon fiber was NOT epoxied then the tooth of the blade would pull strands as it tried to cut it. I would think a shear cutting method would be best.

Last I would check with people that make race cars or components for such.

I know I may not have answered your question directly. But from what I've read ans seen in fiberglass production and a little on carbon fiber use seems similar.

Charles

metalSmith's

Hello,

Structural use has the priority.

Of course the cut edges have to look nice too, not to be teared apart or something. I think of to use jigsaw but somewhere I read it's not recommended and I don't know why! Somewhere it says it's ok to use jigsaw with special blades like here mentioned high carbon or carbide blades with 31-34 tooth per inch. Elsewhere I find that carbide are not good for cutting carbon. There is A LOT of missinformation about this and now I'm almost confused, don't know what to use!

I don't have much excess of carbon to experiment with different tools and blades. And if the piece would be thinner it would be easier to cut with regular tools and blades, but this one is 1" thick.

I did a search on eBay about high carbon jigsaw blades, there are only a few, but I think I would buy some to try.

And yes, fiberglass and carbon are similar and are epoxied almost the same way, just fibarglass is weaker and with some different specs than carbon. I've never cut before none of them just know how are they made.

I used to work making fiberglass signs. We would cut up to 1" thick with a diamond blade on a table saw. A carborundum metal cutting blade will work but won't cut as straight. You can use a sabre saw (hand held jig saw) with a tungsten encrusted blade if accuracy is not as critical. I believe a tungsten encrusted blade for bandsaws is available but it would probably be hard to control if accuracy is important. We occasionally cut carbon fiber sheet with the diamond blades but it was not 1" thick. I think it was only 1/2" thick since that's all we could get. Diamond blade is the way to go. Don't have blade depth set any deeper than needed to cut through. If the blade gets too hot it will warp and not cut straight. You can also use a diamond blade on a skil saw. NOTE! Use a good respirator and eye protection. A dust mask is not good enough. If I was going to cut it on a regular basis I would use a helmet with a window in it and fresh air pumped in. Trust me you don't want that stuff in your lungs or your eyes. Carbon fiber stinks like it's burning when we cut it.

There is a company called Fein that makes a tool that cuts fiberglass with an oscillating blade. Don't know how the toothed blade will last on carbon fiber but you could give them a call.

I don't know why you would be told not to use a band saw. Both the carbon fiber and the epoxy are very abrasive and they will eat your band saw blades. I just use an inexpensive coarse blade or one that is already a bit too dull for aluminum then throw it away when I am done. If you have a lot to cut you can invest in a carbide tipped blade. Be sure the blade is coarse to give room for the dust especially cutting thick material. Otherwise you will get a lot of heat build up. A bit of wax such as parafin will also help.

I will like to add here that Carbon particles may be extremely harmful to the health of the person exposed during cutting of Carbon/Graphite material, hence some kind of nasal air filter to be used while implementing such cutting work which can easily through Carbon particle dust in air.

Yes you are very correct. We in US take special care by providing face protection for air and airplug for sound and eardrum

If it is under my supervision I will force this in or quit my job but thanks God I work in electronic and have implimented lot of check and balance to protect fellow member who come to help us grow.

This is also we implimented in our electronic adhesive manufacturing facility in Chennai India which has websit www.globalappliedmaterials.com and is worth looking in which we took work safety as our first responsibility since they are real assest Global applied materials have

Msyood

try the hydraulic way : punching out for circular cuts ; chopping for straight cuts

For cutting thick carbon fiber...
Use a wet-saw (tilesaw). You can find one that operates like a regular skilsaw as a handheld so you can get into the project vs sitting the CF on a table.

If you can't get the wet type (which attached to a standard hose bib or garden hose).. the carbon fiber will fracture slightly around the edges...

Tip or end fractures are no big deal if you're impregnating it into a coating system such as with fiberglass resin.

You can find this wet saw in stores like Home Depot, Lowes, Menards and Ace, Lehnarts, etc... for about $50 tp $75. The two I own are yellow and made by an offshoot brand called Workforce.

Goodluck!

How about some more information when questions are asked.

You are not cutting carbon fibre you are cutting a carbon fibre composite. There is a big difference.

How many parts are you cutting? One, one thousand, fifty thousand?

Is the part flat? Is it curved? What tolerances do you need?

How did you make the part? Was it hand-layed up? Did you vacuum bag it? Was it made in an autoclave?

What are you doing with it? Is it a really expensive floor for your dog kennel? Or is it part of an advanced aerospace system?

What resin did you use? Did you really use epoxy? Or did you use polyester?

I ask this with all due respect, but the lack of thought that goes into questions on this forum results in misinformation and wasted time.

Good people are trying to answer your question.

Advanced composite materials are difficult to machine. If you cut this using the incorrect tools and procedure you are guaranteed to compromise the physical attributes of your part. No point in using these materials if you don't first educate yourself on what it required to make them work for you.

First, do not cut with a band saw or any other kind of reciprocating saw. You will tear the fibres and destroy the bond between the fibres at their termination and the matrix. This will be the start of premature failure.

Your best bet is to use a 3 or 5 axis router and DVD coated tools to do your cutting. You must use coolant in this application.

Cheers,

Bloefeld

First thanks very much for this huge response! I appreciate this very much!

I did search google about this but I didn't find anything more useful for me about cutting thick carbon composite. Just what to use and what not, in different places different info without telling me why it is like that so can figure out something myself.

Thanks for the link aurizon, I didn't search for that myself. There is some info on some of the links I checked from it.

The machines that you are mentioning are not available in my region, I'm not from USA, I'm from Europe, Macedonia. Therefore I can't think of using them, all is left on hand machines.

Bloefeld asked for more info on the piece, here it is:

Yes, the piece is carbon composite, I believe with epoxy resin, not polyester. When I bought it it was stated as aerospace carbon fiber, and was around $250, 35"x4" 1/2x1". I'm not sure if it is hand-layed up but I think it was in autoclave and vacuumed, because the piece is very good made with no air bubbles and it is twill cloth of 30-40 layers.

I'm cutting only one part from the piece, it is a neck for a bass guitar so priority has structural and after that is the cosmetic look. For the dog kennel I think I would put something thinner and cheaper :).

The part is flat, except the "head" of the neck that it has to be thinned to about 1/2".

Also I found some blades for jigsaw, recommendation from DeWalt, BiMetal Alloy, Wavy 36 tooth per inch, claimed as last longer than carbon and carbide blades. I think they would do the job.

And Bloefeld, yes you're right first for educating and after that doing the job right. The first lesson everyone should know.

If I souldn't use reciprocating saw, what to use to cut the piece when my country hasn't such cnc machines especially for carbon cutting? I don't think they even know what carbon is. Damn. Those blades I found, can they do the job without weakening or destroy the bond between the fibers and the matrix? If water is neccessary during the cut it can be applied from aside, I don't have jigsaw with that option. Or maybe sandwiching it between plywood or regular wood like Tippycanoe mentioned? Will this help?

the people who made this carbon fiber can advise.

or else use google.

this search gave me 20,000 hits, one of which might suit you. just look into them

http://www.google.ca/search?hl=en&q=%22carbon+composite%22+%2Bcutting&btnG=Google+Search&meta=&aq=f&oq=

Look at JEC online, SAMPE Journal, High Performance Composites, and Global Spec for souces of information about composites.

Cheers,

Bloefeld

Aerospace industries manufacturing carbon composite components make use of water jet cutting extensively for the following reasons.

· Create complex shapes using composites with precision water jet cutting.

· NO Heat Affected Zone (HAZ) which is ideal for composites and more.

· With speeds up to Mach 4 or 90,000psi water pressure

· Ideal for cutting up to 8" of composites materials depending on density of product.

· Eliminates most secondary finishing… no burrs or rough edges

· Safe for the Environment; no toxic fumes or dust and garnet is disposable.

· Omni-directional cutting. Minimal tolerances. No wasteful raw materials.

· Cutting heads do not have to be changed out during manufacturing avoiding aggravating delays.

· Thick or Thin, Waterjet cutting is the most flexible process in manufacturing from cutting granite to foam.

· Minimal set up for automated cutting process and minimal downtime for quick seal change.

· Cuts without melting.

· Can pierce material directly without the need for a pre-drilled starter hole.

· No tool sharpening

· One head for all applications, no guessing, no need to change bits.

· High or low surface pressure flexibility for sensitive or thick materials

· Tolerances (at ±0.003")

There should be no problem out sourcing the cutting by water jet which is common enough now a day.

Carbide tooth blades or better are recommended for cutting carbon composites. A router with a carbide double cut deburring tool should do. Will also give you the control to cut the curves.

The band saw a vertical type for wood is what you ask about may turn to fast. which can be corrected. The width of the blade to support carbide teeth may make it hard to turn the small curves. Biggest reason for not using one that I can think of is the dust from the cutting getting in to the saw and doing damage and shorting its life.

We had a more difficult challenge years ago. Cutting epoxy with mica and other problem filllers, all bonded to thick copper. We had to cut and leave an edge that we could examine minutely. We simply used a cheap blade on a bandsaw, as was mentioned above. It is hard on the blade, but it makes many cuts before it becomes useless. Soft metal is an enemy of fine abrasive cutting, so we knew that path would not work for us.

David

Hello ModulusMK,

This may vary greatly between applications, but I am a cyclist and to cut carbon fibre handle bars, forks, seatposts, frames, etc. there are usually custom vices to guide a hack saw. We would also tape the area to be cut with masking tape then cut through the tape and carbon. The tape helps to avoid fraying of of the fibres as you cut. For the same reason, use as sharp a blade as possible.

Best of luck!

-MechMatt

You have bit into a pretty tough project for your bass neck. To be honest, I would abandon the method you are using. Instead buy the necessary materials to do a vacuum bag lay-up, build a plug (a piece of wood that looks like what you want your finished part to be), then a mold, and then lay it up.

Be careful with cutting any fibre reinforced product. As mentioned earlier the little particles are deadly to your lungs.

The alternative is to see if you can find someone who is a skilled machinist with a big enough mill to cut this part. He only has to drive the spindle at 10,000 rpm or so to get good cuts with carbide tools. He should also be able to mill the surface to near net-shape. Then you will have to sand it down until you are using 200 grit sandpaper. Put a final coat or two of epoxy on it and you will have a great looking part.

Cheers,

Bloefeld

:), I know it's not an easy project, but I want to try. When I already bought the piece I would like to make it. If there are any further necks to make the first thing on my mind would be MOLD :).

I read about the dangerous dust from carbon fiber while machining, so I'll do my best to keep it at low level and protect myself as best as possible.

So I guess I'll buy those BiMetal blades as recommendation from DeWalt and give it a try.

Thanks again!

Please please at least do wet cutting, grinding, polishing to minimize damage to you and your wife, kids, brothers, sisters and parents along with people surrounding you.

We work to make life of humanity little better and not to spread cancer and other toxic deceases.

Best of luck in minimizing damage to you and people surrounding you.

Yes Masyood, of course I'll try to be very careful and will try to use water cutting and sanding to minimize dust to keep humanity safer as possible. For me that's always on the first place!

And one more question, here I got recommendations for carbide blades, but from DeWalt I got recommendations for BiMetal blades. What to use now? Somewhere I read that the BiMetal blades last longer than carbide and carbon ones...

You are correct but carbide blade is harder and gives better cut than bimetal blades

This is just engineering balance and engineering needs for the product to be used and abused by end user

Masyood

Is there any difference in manufacturer of the blade or...?

I found something on eBay, carbide ones, 5 blades for $9. Hitachi makes them, JC10 model I guess that is. There are also some Tungsten Carbide blades, 10 blades for $6.

Anyway I'm cutting only near 6 foots in total length, nothing more.

Dear ModulydMK,

I have cut a great deal of carbon fiber using abrasive blades (for ceramic tile) which are commonly available for all types of saws. The band saw version would likely hard to get, so I would recommend using the skill saw. The problem is going to be clogging the blade, so don't rush it. Using water to cool and clean the blade would be great, but dangerous with a skill saw! (Perhaps a friend could use a spray bottle to apply the water, and did I mention MESSY!)A diamond bladed tile saw designed for using water is only good for cutting straight cuts. (It does make smooth cuts.)

Burning does weaken the edges, so that's another reason to go slow.

DO USE A MASK! If dry cutting, it helps to have a vacuum cleaner as close to the saw as possible, not to mention better for your health.

Carbon is really hard and strong. Done right, it has a tensile (pulling) strength just short of 1 million psi.

You could cut the pieces a little oversized then use a router with one of the abrasive bits to bring it to finish size (and remove any splintering). Again, "easy does it" to avoid burning. This is what I would do, and it would would not splinter the edges. A little experimenting and you will find the optimum amount of extra for the rough cut.

That's all I can think of at the moment.

Good luck with it,

I have had 1" thick glass cut complete with granite inlay in fine detail with a waterjet cutter. they say theses can cut aluminum/steel 18" thick!!

Bill H., do you think of this blades will cut carbon fiber smoothly?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=350193031947&_trksid=p2759.l1259

ModulusMK,

Yes, the blades will cut as smoothly as any. You still may want to finish sand the piece for cosmetic enhancement.

I am curious if the surface layer is woven fiber. It is common to have the interior layers of straight, nonwoven fibers laid at alternating + and -45 degrees with an outside layer of woven material. This generally would be put in a heat press under a lot of pressure and vacuum. This would have a non-stick treatment on the press plates or a layer of non-material. The finish is really smooth and has a 3d appearance.

If drilling the material use a very small drill for a pilot hole all the way thru. Then start drilling from one side part of the way and finish from the opposite side. This will help avoid break-out of the surface fibers. Drill bits made for composite vary, but usually have a very steep angle of the cutting edges which helps with the break-out problem. Finding them afford-ably is a problem. The best ones have diamond cutting edges!

You can clamp the piece between two pieces of aluminum on a drill press and minimize the breakout problem. Drilling by hand will result in the drill grabbing and pulling itself into the material and de-laminate it. Also, I think I was successful using a counter-sink tool to do the first part of the hole (after the pilot drill) slightly larger than the diameter of the finish drill size (do both sides).

Got to go, good luck,

As it looks from side I think all the layers are woven. Twill weave it is. But I'm not sure if they are on the 45 degree, I think only 90 by the yarns in the weave but still not sure.

Yes I have to drill it, 4 holes for tuners plus 4 smaller for attachment. First pilot holes and after the real size. I must be VERY careful with every part machining this black monster :). I thought of drilling them with some tools that I have at home but they're for wood so I have to buy carbide ones. The ones I have look something like this (without the dots, I put them to make the pic look right) and they are not round, flat only but have very nice drill in wood.

|........|
|/\. ./\|
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Is the manufacturer of the tools important or not, those diamond tile blades I found from "THK" Hong Kong company are very cheap so it's a little bit strange...

ModulusMK,

My experience is that the cheaper blades may not last as long, so for small projects they'll be fine. If you were cutting material often as a tile person might, investing in better blades would be a good idea. The cheaper blades are likely to have less diamond in them and the quality of cut drops as well as the force to cut thru the material will increase. For small short jobs like this it should be fine.

I did try the type of bit you talked about, but do not remember what kind of results I had.

There is a spade looking type bit which will cut ceramic tile and glass available. They are made of tungsten carbide. Here's a link:

http://cgi.ebay.com/C-2-Tungsten-Carbide-Glass-Cutting-Drill-Bits-Plastic_W0QQitemZ140315801247QQihZ004QQcategoryZ50383QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

good luck,

Thanks to all, useful answers i did got. Little by little things are getting clearer.

Now it's only left to find the blades needed for work and try! After I try I'll write back the results, maybe not much fast but I will.

Best to all!

I've cut the carbon fiber. The diamond tile blades have done the job well. It's a good cut but it needs fine 'fileing' of course. Now I'm searching for carbide router bits to route it for the necessary thickness of the head and drill the holes for mounting on the body.