I have been looking for a plasma table that would fit my budget and my shop. We design and manufacture custom machines, control systems and automated machines. No a very good environment for most cutters. Smoke and water spray is acceptable for a steel fabrication shop but not relay good for a machine / electronics shop. Plus I build drag racing cars for a hobby so lots of abrasive dust isn't good for that either.
I started looking at water tables but they look messy and well I won't be running the machine every day and what do you do with the water? So down draft was the way to go for me.
The cnc section is built with 8020 profiles and linear bearings. I know that .001 accuracy will not be possible BUT, this is plasma cutting not machining. I can easily get .004 accuracy with this setup and save lots and lots of money.
We had a few steel plates cut by laser cutter, $500 to Ebay suppliers, added a few bolts and some steppers and in 1 day had a working XY table.
I decided to make the machine 48 X 30 " so it wouldn't take up lots of shop space. The gantry is 50" long so scaling up to 4' X 8' is very easy and since the X axis is rack and pinion the same gantry can be used for only a couple of hundred bucks more.
Right now we are using a 1 micron filtration system at 900 cfm. . If we need to we can add electrostatic filtration as well But keeping with our budget, we are trying not to.
If anyone wants some drawings or steel parts I have some left ( I had to pay a minimum so I cut more ) . I will keep posting as we go along keeping you informed.