Cnc Cutting 1/4" Baltic Birch - What Bit to use ?

Hey Guys,

Im receiving my cnc this week and wanted to get some help on cutting 1/4" Baltic Birch. The machine is a laguna Smartshop with ATC, want to see what bits i should test first. Im looking to get as close to a end product as possible, Clean edges, clean top and bottom with no splinters. We make parts for displays so we are trying to cut down on post production finishing.
I was thinking a 1/4" compression bit might be a good starting point and work from there. I also had the thought of using two passes - The first would be a down spiral and then finish with a up spiral so the plywood surface doesn't get damaged. We are currently using laser cutters to create the part but its slow (100 watt lasers dont cut this stuff fast) and it leaves the black edges (Pain to paint over).

Any suggestions would be helpful

I would just single pass it with the compression bit if it works (radius) for your parts. If you have vacuum hold down and your parts stay flat you may be able to do it all with a less expensive down spiral but if your looking fort dead clean two faces the compression is going to help. One thing you may have to check though is where the compression is on a 1/4" bit. 1/4 material is pretty thin and Id imagine the compression is short enough to work. I honestly never have any problems with edge and face damage with straight plunge cutters. Perhaps a 1/2" shank, 1/4" x 1" straight plunge. Would be far less expensive than a solid carbide compression bit and much easier to sharpen.

Give LMT Onsrud a call. They are very helpful and will suggest to you exactly what you need for your process. Highest quality bits too.
800-234-1560

Robert...
Due to the thickness of your material, I would go with a 1/4" mortise compression bit. Mortise compressions have a shorter upspiral section that allows thinner material to be cut without surface splintering.

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Originally Posted by Gary Campbell

Robert...
Due to the thickness of your material, I would go with a 1/4" mortise compression bit. Mortise compressions have a shorter upspiral section that allows thinner material to be cut without surface splintering.

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Would you say a 1/2" mortise compression bit for 1/2" material...or is that not right? Thanks!

Grab yourself GWizard Calculator too... it will get you pushing bits as hard as they can go for the surface finish you want way faster than any other tool.
https://www.cnccookbook.com/cnc-rout...ds-calculator/


I've been using it for many many years and it's allowed me to have the confidence to really really push my machine. The harder you push the bit, the more tool life you get and the faster your job is complete!

Thanks for the tips guys.

Mark Just bought Gwizard still playing with the settings but its giving good estimates so far.

Garys suggestion worked great - We went with a Amana 1/4" Mortise Compression bit (46350) and they work well. We have probably went through about 30 of them in the past year, they leave a clean edge and they dont affect the plywood finish.

Quote:

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Originally Posted by Robert Bonenfant

Thanks for the tips guys.

Mark Just bought Gwizard still playing with the settings but its giving good estimates so far.

Garys suggestion worked great - We went with a Amana 1/4" Mortise Compression bit (46350) and they work well. We have probably went through about 30 of them in the past year, they leave a clean edge and they dont affect the plywood finish.

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Oops, didn't realise this was a resurrected thread until you mentioned "past year".

Try one from Onsrud, Kyocera, CMT, or pretty much anyone else. I've found Amana's carbide to be pretty much identical to Freuds, easily chipped, gets blunt easy, sub-par in general. I *love* their tapered carving bits - but their endmills suck. Running a Kyocera bit through walnut - dead quiet cut, lasts me 2+ weeks - change to Amana of same OAL, DOC, Width - high pitch scream through the whole cut. After the first toolpath finished I have 2-3 small nics or chips on the leading edge of the flutes. I went through about 10 and now won't buy anything but their tapered carving bits.

Running in brass, the kyocera/onsrud bits ran through dozens of pieces. Amana's bit chipped (more like tore apart) on the leading edges and had brass welded to it in under 20 seconds - same toolpath, same brass, same conditions. That was the fancy rainbow Spectra coated ones too that cost 3x as much as a AlTiN kyocera bit!