Carbide Cutters Wearing Out in Melamine

CNC users troubleshoot a case of short bit life in melamine. December 14, 2005

After this weekend, I am still in the dark over cutting 3/4" G1S melamine on our CNC with 3/8" diameter carbide compression bits. I have read all the posts about running 50 -100 sheets and I am in pure amazement. We ran this weekend and cut quality goes to hell after 10-12 sheets. We are running Panolam stock and we are getting a lot of fuzz at the core center along with voids from packing the chip down. The edge quality is giving us trouble with 1mm PVC edgebanding, as all these little divots and bumps show through the PVC. We have adjusted speeds and feeds as suggested at this forum, to no avail. We are using Vortex and Courmatt compression bits for all of our processing.

What are we doing wrong? I can't even imagine what we get for cut quality after 25 sheets, let alone 50 or more. I need help!

Forum Responses
(CNC Forum)
I'm using Courmatt 3/8" upshear/downshear compression bit, and we are on about our 500th sheet of Panolam 2S Thermofused mel and are still getting a perfect cut on both sides. Do you have sufficient dust collection to remove the excess debris that might be getting caught between the bit and the material? We're pretty new to CNC, but have perfect cuts and smooth edgebanded surfaces.

Dust collecting is a must, but I have two questions. First. How many passes are you taking to cut your parts? Are you using a clean pass? Second, are you making a thick sawdust or are you making a super fine dust? Remember - it is the heat that dulls tooling. If you are getting a bad cut that is affecting your edgebanding, double check that your head or heads are straight up and down.

If this is off at all, you won't get a good edge. The tape will stick to one side and not the other. You can see this if you run the part through the glue line without the tape - you will see that distribution along the edge.

I run 3/8" up/down comp tooling in everything - hard wood, mel, MDF, from a lot of different companies - and I get long life out of all the tools.

500 sheets? I find this a little hard to believe. You should be able to get about 100 out of a good quality cutter.

Make sure your speed is up. You want to run the fastest feed rate you can at the slowest rpm you can while getting the cut quality you want.

You should be receiving 60-80 sheets, not 10-12. Two things can be happening:

#1- There is melamine in the market that has aluminum sulfate in the mixture, which helps it to be more resistant to scratches. You require a 3+3 compression tool.

#2- A pine core, vs a harder composite core, may not provide the chip clearance you require.

I have also run into this same problem with Panolam. It seems the flake is too coarse and killing the tooling. The Panolam rep came in and replaced our broken tooling with diamond cutters and paid for all resharpening (we had about 25,000 sheets to cut and time restricted us from changing material). I would talk with your panel goods rep and your tooling guy.

25,000 sheets? Of rectangular nested parts?

May sound stupid, but make sure you're not using a climb cut - this will wear out a tool super fast and give a horrible cut on the melamine. Cabinetvision defaults to using a climb cut on all materials.