I have been asked to help build a plasma CNC capable of cutting 3 x 1.5m x 25mm thickness steel.

The sketch is based on my previous CNC Router but with the differences that the Y and X axis will be rack and pinion.

I have budgeted £6K to £7K for this build, am I in the right ball park?

I intend to use for the Y axis 2 x Nema34, 8.7Nm one as slave. With a spring loaded pinion gear box with tooth belt and pulley reduction. To achieve a speed of 12,000mm/min.
Is this the right way to go if so – Rack: Mod 1, Pinion Size? Reduction Ratio 2:1 ?
(or show me a link for calculating)

X axis 1 x Nema23, 4Nm as above.

The drivers will be Leadshine AM882, 68V Toroidal PSU and CSMIO/IP-M4-axis Ethernet Motion Controller. Basically all copied from my existing set up.

I have used the same aluminium section for the X axis Profile (45 x 90S B-type slot 10) two full lengths (1980mm). I believe this will be strong enough as there are not the same forces on a plasma that there are on a router.

The base of the Z axis clears the table by 40mm is this too tight? Should I lower the water bath/bed

The Z axis is again a copy with a 350mm RM1605 ball screw is this to big? Too much travel?
(Nema23, 4Nm)

I will come back with questions on THC and the actual plasma torch when I find out some more details of what is going to be used.

Probably want to add some more steel to the frame somewhere?

Thanks for any suggestions.

Robert

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