Help Routing MDF?

[lgroulx200]

Hi,
What is the best way to router 3/4" mdf? I just finished my new CNC machine. I want to change the X axis from a moving table to a design like Joes. I have tried using a 1/8" and 1/4" straight router bit cutting 1/8" and 1/4" thick. I have tried slow cutting and fast cutting. I have broken 2 1/8" bits and burned my 1/4".

Larry

[CLaNZeR]

Hi Larry

Slow it down I reckon and do not cut so deep.

Try cutting the depth at a pass of 0.08 " or less at say 20IPM and then first increase your travel speed, then maybe your depth until you find a cutting combination that suits your machine and spindle.

If you are determined to cut deep cuts then be prepared to reduce your travelling speed.

I always start slow and small depth passes and increase till you know your machine and spindle limits.

Once you have cut the material once, make a note of it and do the same for each material you come across.

Regards Sean.

[Jason Marsha]

I cut MDF on my JGRO at 40"/min at 1/4" (6.35mm) depth per pass with a 1/4 spiral upcut bit. My plunge setting is about 6" /min since the JGRO is not super rigid. I have however plunged faster when I forgot to edit the Z feed rate and ended up plunging at 40" /min, the only problem being the head rocks back a little.

With a new bit faster feed rates are possible but as the the bit dulls the feed rate must be reduced.

You need to cut mdf with solid carbide bits or better. The upcut spiral allows for faster feed rates because they clear the cut debris by feeding it up out of the hole.

As Sean said "Find a cutting combination that suits your machine and spindle".

Jason

[Jason Marsha]

I forgot to add that with the 1/8 bit I would normally reduce my depth per pass to about 1/8" to 5/32".

Jason

[joecnc2006]

I cut MDF at 80ipm, 2 flute upspiral 1/4" carbide bit at .15 passes, works best when bit is new or just sharpened, I can even hear the difference in noise from cheap bits to good bits being not as loud during cutting. (get rid of the straigh cut bits)

[lgroulx200]

I will go and purchase some of those bits tomorrow.

Yesterday was my first time cutting with the machine. For the most part I am very pleased with everything. I had to go and check the nuts and bolts to see if any came loose. I was cutting and my Z leadscrew slipped (unscrewed?) from my hose clamp - hose coupler and dropped into my table.

I downloaded Joe's DWG drawings to get an idea for my new X axis. I will use my current machine to cut the pieces.

Thanks again

Larry

[ger21]

If you can slow the spindle down, do it. If the bit's burning, you're cutting too slow. depends on the router your using, but even a laminate trimmer should have no trouble cutting 1/8" deep probably up to 100ipm. So go as fast as the machine will go. If it's flexing, take lighter passes, but DON'T slow down.

[Claude Boudreau]

Originally Posted by ger21 If you can slow the spindle down, do it. If the bit's burning, you're cutting too slow. depends on the router your using, but even a laminate trimmer should have no trouble cutting 1/8" deep probably up to 100ipm. So go as fast as the machine will go. If it's flexing, take lighter passes, but DON'T slow down.

1/8 deep 1/4 diameter single upflute?
My vacuum is not very good, dust seem to build up ,increasing working temperature.How can you concentrate the Shop Vac at the cutting edge?How much horse power do you have to go 100ipm?