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Dean jeffery
02-07-2016, 07:39 AM
Not worked with carbon fibre before but some general Speed Feed and DOC will help, so if anybody's used this material before then any help is much appreciated.

It's pre peg 3k 100% carbon

At the minute I'm only cutting 0.25 thick carbon, but soon I'll be cutting 4mm, the cutter I've been using is a coated carbide 3 flute 2mm bit.

Cheers.


Now the proud owner of my own personal CNC machine happy days.

magicniner
02-07-2016, 10:46 AM
I was recommended burr style bits for thin work, and to prevent delaminatin on both upper and lower surface compression cutters for thicker stuff.
I seem to remember I found the information for feeds & speeds on the cutter manufacturer's site,n

- Nick

Dean jeffery
02-07-2016, 04:10 PM
Cheers Nick I will check those out


Now the proud owner of my own personal CNC machine happy days.

Boyan Silyavski
04-07-2016, 11:00 PM
I have never cut but should be similar to fibreglass. Take care of the stick out as this severely could change things. I calculated all based on 20mm/ the tool shows 20mm from collet/

Hope that helps

18855

Dean jeffery
05-07-2016, 04:02 AM
Cheers boyan that does help

Ended up downloading an app came back with this info

http://uploads.tapatalk-cdn.com/20160705/1fd10d438a0407268194311e5e622735.png

http://uploads.tapatalk-cdn.com/20160705/5500016878ad9edab29213cc29d9aeb2.png


Now the proud owner of my own personal CNC machine happy days.

Dean jeffery
21-08-2016, 08:17 AM
Well thought I'd update this thread just in case somebody needs some info.

I've cut 12 plates of carbon 293x129x4 and done a few various parts from the plate.

Had a few trail and errors with cutters but found a cutter that works a treat and just 55p yes 55 pence, once they have done 1 plate they go in the bin.

DOC I've been doing was .5 mostly cutting 2mm WOC at 24k

http://uploads.tapatalk-cdn.com/20160821/e24b5078061c71789edc0a9dd9cff16f.jpg

magicniner
21-08-2016, 09:29 AM
Dean,
That looks good, how's the edge finish?
If you have a play with single flute carbide and can get them to work for you then sharpening is very easy, although you'll need magnification and a diamond wheel they can be ground offhand,
Regards,
Nick

Dean jeffery
21-08-2016, 09:53 AM
Cheers Nick I'm impressed with the out come, and doing this in ones garage compared to proper company's mine are and not been big headed are better.

TBH Nick the edge is fine no delam or nothing, I use what I thinks called a corn cutter.
The chassis plate needs a finish pass round the profile of the chassis plate, that's the big part in the pic only because a few bits are needed to be spot on.
But it does leave a tinny lip on the carbon and most would not bother TBH but a simple rub round the edge with some 1000 wet and dry removes it, or a simple deburr in a matter of seconds.

But the cutters I use Nick it's pointless even trying to regrind them mate, I can't even add cutter cost to parts theirs 120 of parts in the pic VS a 55 pence cutter the end mills are free :)

http://uploads.tapatalk-cdn.com/20160821/6e5d664ebfb810dab816e239e7f4704c.jpg

Clive S
21-08-2016, 10:44 AM
Dean
found a cutter that works a treat and just 55p yes 55 penceWould you be happy to share a link to the cutters.:whistle: Nice work by the way.:applouse:

Dean jeffery
21-08-2016, 10:52 AM
Sure Clive

eBay item number 221965675192 don't let the Chinese put you off they came in around 6-8 days, and I'd bought 1 cutter from the UK and snapped in 55 seconds using the same speeds and feeds.

Boyan Silyavski
21-08-2016, 12:08 PM
Great job. As you say the price of cutter is not worth calculating in the price of the pieces.

One question: How do you fix that brass/copper?/ to the plate?

cropwell
21-08-2016, 12:13 PM
Ta Dean,
I have ordered some to try.

Rob

Dean jeffery
21-08-2016, 12:28 PM
Great job. As you say the price of cutter is not worth calculating in the price of the pieces.

One question: How do you fix that brass/copper?/ to the plate?
They are pressed into the holes mate I made the holes .1 under size, carbons pretty soft so needed a tighter fit.
If it was alloy 0.02 would be enough.


Ta Dean,
I have ordered some to try.

Rob

Don't waste your time trying any others mate I got some coated ones of the same style and not worth the extra money, I've only tried them on carbon, plastic and MDF.

http://uploads.tapatalk-cdn.com/20160821/6b7ad162466a73aa81d0da5d86b2af19.jpg

1 cutter did all this that's all the holes and profiling but finished the profile with an end mill, I have another program that does 20 parts per plate just the smaller rectangle parts but the cutter was worn at the tip and makes the edge tapper.

Boyan Silyavski
21-08-2016, 01:01 PM
just bought 10 of the cutters, soon will have to cut some composite panels- g10, micarta.

Clive S
21-08-2016, 01:55 PM
Sure Clive

eBay item number 221965675192 don't let the Chinese put you off they came in around 6-8 days, and I'd bought 1 cutter from the UK and snapped in 55 seconds using the same speeds and feeds.Thanks for sharing

Jonathan
21-08-2016, 07:06 PM
Thanks for sharing

+1

I've tended to use diamond burrs, the type you find in rotary tool sets, for cutting carbon. Even less than 55p each! Here's a recent example:

19056

And a not so recent (T-5 years) example (probably already posted somewhere on this site):

1905719058

I'm still using that keyring - amazed that I've not lost it yet. I'll splash out on the cutters suggested here for the next part and compare...

Dean jeffery
21-08-2016, 07:28 PM
Deffo splash out Jonathan that carbon looks really chewed up :(

This ones not been deburred or anything yet, but as said just a quick rub round the edge with wet and dry and it's burr free :)

http://uploads.tapatalk-cdn.com/20160821/91eae1070840badd080ed9c8c07cb9cc.jpg

Jonathan
21-08-2016, 07:43 PM
Deffo splash out Jonathan that carbon looks really chewed up :(

It's just the edges, which as you've noted, clean up well with sanding. I agree it's not ideal.

19060

Still, for some things the finish is a little hard to discern in when the part is in use ;)

19059

Dean jeffery
21-08-2016, 07:56 PM
Well I'm sure you'll see a big improvement with the corn cutters mate, but minimal clean up for me is a big deal and only a few need clean up [emoji106] the first few parts come off needing nothing but a wash.

But when selling parts if they don't look 100% spot on then and rightly so people complain.

Billythefish
26-08-2016, 10:32 PM
Good post! Thanks...

how did you hold the carbon sheet? Screw and glue?

cheers, Billy

Jonathan
28-08-2016, 05:44 PM
Screws where feasible, double sided tape where not.

Dean jeffery
28-08-2016, 05:48 PM
Good post! Thanks...

how did you hold the carbon sheet? Screw and glue?

cheers, Billy

Sorry missed this post I used both DS tape plus screwed

http://uploads.tapatalk-cdn.com/20160828/d27c5a26df54f3c8547bb5bafa9e928f.jpg

JAZZCNC
29-08-2016, 11:28 PM
Thanks for sharing

He didn't thank me other day when I snapped one while setting machine up. . .Lol

Dean jeffery
30-08-2016, 12:36 PM
Lol Jazz that won't no cheapo Chinese cutter though, it was my one and only super plastic cutter :( been replaced by cheapo Chinese to compare [emoji106]

Flyer
21-10-2016, 11:01 PM
Looks good Dean, I've just ordered some:thumsup:
How are you cutting the countersinks?

Dean jeffery
08-11-2016, 05:04 PM
Sorry flyer I missed this :( I'm doing the countersinks with a coated carbide sim to this one eBay 222222270634 I use an 8mm bit 4 flute.

Machining then I use a profile method 3 passes, doing then in Z caused chattering and was slower :)