Cutting plywood

[Stockbub4]

Well, I am just getting back to playing with my Shopbot and trying to get my techniques down. I am cutting 3/4 birch 11,500 rpms at 6 IPM. Making decent chips, but looking for suggestions. I am noticing there are lots of chips in the crack that the vacuum is not picking up. I am using a 3/8 compresson bit.

I am drawing cabinets in Artcam. Any and all tips are appreciated.

Bubba

[Stockbub4]

How do you get chips vacuumed up. That was the question.

[Gary Campbell]

Martin...
Compression bits have a tendency to leave chips in the bit kerf. If you use an onionskin strategy, most are removed.

You can increase the CFM of the dust collector, use a more efficient, or better sealed dust foot to increase chip pickup with your existing cutting parameters. Also make sure that the dust foot height is adjusted properly.

[Stockbub4]

How do you set up an onion skin. Is it effective. What is cut quality like? I use artcam to draw cabinet parts.

[Gary Campbell]

Martin...
Onionskin is a toolpath strategy in where you first cut down to within, say .035 of the bottom surface of the material on all your parts, then come back, and starting with the smaller parts, cut thru that last thin layer, or "onionskin".

In ArtCam you would generate an outside profile toolpath with proper stepdown for your cutting bit applied, usually in climb mill direction to a depth of the material less .035. Then a second toolpath is generated in conventional cut direction, using a stepdown (or pass depth) greater than the thickness, so that it cuts in a single pass.

The first(climb) cut results in any bit/machine deflection being transferred to the waste area. The second cut(conventional) is under very light cutting load, so the result is very accurate parts and great edge quality.

Once you have tried this, you can save these toolpath's as templates to use in the future.

[Stockbub4]

So you make one toolpath (in Artcam) to leave1/8 or 1/16" inch in conventional. THen make another toolpath in climb the entire depth and do this one in climb. Then save bothtool paths into one cutting. One the second tool path make sure you have cut smallest parts out first. Sort of makes sense and I bet the quality is much better.

[ken_rychlik]

Backwards Martin.

Almost through in climb
Then cut all the way through in conventional.

If you select the parts one at a time, you can have partworks run them in the order you selected them. You have to un check optimize.

I don't know where you are in Texas, but if you close to Houston give me a call if you need help.

Ken