Looking to build a CNC machine

[mitchDM]

Originally Posted by ger21 For one, cutting steel requires lots of coolant, which doesn't mix well with MDF. And second, while it's a decent machine for light work, most who build the JGRO find that is flexes too much, and eventually build another machine. If you'll only be cutting steel, you might want to look at building a plasma cutter.

How expensive is it to build a plasma cutter (sounds expensive) and are there any plans you would recommend i can look at or buy?

[Switcher]

The cheapest thing your going to cut metal with is a oxy torch, the good news is you can cnc the torch, & stay low budget.


http://www.cnczone.com/forums/showthread.php?t=24187


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[Switcher]

You could start cheap with the oxy torch, than upgrade later on to a plasma with a few mods. to the table.


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[ironDigit]

Switcher is completely right.

there's no sense in building a machine dedicated to cutting steelPLATE by means of milling.Some kind of torch is the way to go wich is a very big plus because a torch cutter will cause a lot less stress and pulling forces to your frame except when rapiding and other fast moves wich means you can save by using smaller motors then when milling and keep your design "lightweight".If you want to use the machine for a long time i wouldn't recommend mdf cause it will deform and all the gasses from the bath underneath your workpiece could eat into it.

[mitchDM]

Thanks for the advice, i'll have a look around and see what i can come up with.

[mitchDM]

@ Switcher - How good is the finish on the cut, from what i can see it seems quite rough.

[ironDigit]

when cutting with plasma you'll have to change gas/mix ratio's and pressures according to the material at hand to maintain a clean cut

When thight tolerance is required finishmachining on a mill/lathe is unbearable for as far as i know plasma torches can't cut with hundredths of an inch precision and my guess would be that the heat will cause some deflection.

If looks are all that matter sandblasting polishing or a vibratory polisher would be sufficient.

i haven't got any experience with plasma cutting myself and all above i have read here at the zone and interpreted as good as i could.