Cutting Cork? Suggestions?

[scottp55]

Morning all, I got a PM from Spain yesterday--He'd seen me talking about cutting cork for fishing fly boxes(we went high strength magnetic so never cut cork) and thought I might have a clue as how to get a clean cut in 10mm agglomerate cork---NOT:)
His first choice of bit would not have been mine as I've had problems with tearout with my 2 Onsruds of that style. Looks like he's cutting all the way through and needs 2 good sides AND a good cut finish. Not sure if he's profiling ON the line or has a vector and is cutting INSIDE. My first thought was to to try my .125" 61-040's so I wouldn't be using 180 degrees of the cutter and could use either climb or conventional options. Second was maybe a compression spiral, but still have had no need to buy one because of the work we do, so don't know anything except what I've read.
Ideas?
Thanks,
e-mail copied pasted with his pic of unsatisfactory finish pocket.

Hi Scott
Thanks for you quick reply.
I sent you a picture of what i've done with a cnc and i was using a bit for wood.
I was cutting a cork sheet with 10 mm thick. It came out like this. The cut was made with 11 mm because it's supposed to cut from one side to the other.
It's not bad, but i think a cnc can do better.
I think i was not using the right bit, the guys on the forum talk about onsrud 65-025.
What do you think?

Regards

[shilala]

In my way of thinking, I'd use a foam cutting bit. Like for mooshy foam inserts.
A buddy of mine was doing a lot of foam cutting for camera cases and travel humidors, but I never found out what he ultimately ended up using.

If I were testing, I'd move slow at high rpm. When I was messing with the foam, that seemed to work best.

That said, a laser would be ideal, I'd think.

[bob_dodd]

First let me say I never cut cork , On you tube a guy is using a pressure foot and a drag knife and maybe vacuum hold down , looks like good results ,

[gene]

I think a laser would come in handy for this job . May think about sub this work out

[scottp55]

Thanks people, Nothing to do with this personally--Just a PM from the Blue and trying to help a Newbie out:) Don't even think he's a Shopbotter. Got dimensions(4.331X.216") of pocket so tossing a piece of cork tile(old/dry 1/4") and going to try a couple cuts as well as grooving with a ballnose to see if my original idea for fly boxes would have worked.
It's got me curious now (like thinned shellac penetration of MDF:)
Copy/Paste of another e-mail from Nuno.

Like i told you the cnc is from a friend of mine, and we go to his boss factory to do some tests.
He, like me, is flying blind with the right bit speed and settings. He has a vacuum table that works very well.
We are two rookies trying to get some where we don't have much experience with cnc but lots of will to learn.
Thanks for the link, just read it . it's very good.
Take care

[scottp55]

Left to right is Onsrud 61-040/ PreciseBits .117"fishtail/Drillman1's .125"2F up $4
All same drillpaths left to right --just the bit changed
bottom= climbcut slowerfeed 14k
after bottom row all cuts conventional
second row up exactly same as bottom but conventional
Then Amped speed to 18K
and 2 top rows were pocketed- not profiled.
Pics stink but so did light and photographer:)
Tried Ace Hardware green painters tape on their fiberglass carpet tape so I have a hope of getting it off the backing board-green tape didn't QUITE have enough Oomph for cork, but first time I've tried that technique and I like it--and dust foot pressed material fairly flat.
LOUSY Cork, but higher RPM and slower feed with a decent 2FUP I'd feel comfortable with. Even the Point Cutting Roundover would work with denser/newer Cork I think.
Maybe can get better pics when I take it off, but want to try fluting a trough and BN groove tomorrow.
15 toolpaths so e-mail me for .crv if interested.
scott

[scottp55]

Finished the series with a Whiteside .125" Downcut--Result comparable to the Onsrud 61-040(not very good)
BEST CUTS
PreciseBits .117" Fishtail 2F 1,.5,18K Conventional .06"pass depth
Kyocera .125" 2F EM Up
VERY Clean cuts on both, but Fishtail had the least variance in the cut with all the different feeds/speeds and pass depth. Kyocera had a smaller sweet spot.
Bob D did a little surfing for me and said most people steam or soak the Cork before cutting, but to keep apples to apples all were cut on this very old/dry Cork.
Make sure to cut ALL the way through as you're NOT going to sand it afterwards. I also wouldn't go Very much more Tack than the painters tape or you might have trouble getting it off clean. VERY poor Cork to test with but it was all I had.
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