Building a plasma table, need advice.

[Boyan Silyavski]

I'm still here, thanks for the advice :-)

i dont want to build anything over kill, seems pointless when I see the most important factor being control and precision, it's not driving any force so I fail to see why stepper motors are the choice for so many plasma tables when they draw so much current regardless of work done, closed loop servo seems the way to go and I don't think they need to be very big.

be interested to know if people run servos direct drive or step them down with ratio to give more accuracy, I would like to reduce it to so that I have no backlash in the drive.

is there a go to liner rail with screw drive already built in for the X and y?

That was a question i wanted to know, why can you not pump the water down the drain?

And yes guys take it on board I pissed you all off, sorry :-)

OK. if you are serious from now on, you will be helped.

Lets start from the beginning:

-How big you will like the plasma table to be? working area
-Z travel?
-do you plan to cut square tubes? Round tubes? if yes how long?
-aluminum , welded steel, mixture or aluminum profile structure?
-only dedicated plasma machine or you will try to do other stuff also?



Some answers:

-Hiwin 20 rails is best, same price as 15 size but easier to mount and overall engineer. There is one other rail i like better but is more rare- MGW Hiwin, though its ideal if you use only one rail on Z and X. Which you could do with the HGR also

-1605 ball screw for Z, 1610 for X. Nope, better design them yourself and order them from China. later we will point you from where. Y? still not clear until you say what length will be your longest axis. If you want to cut 2500mm long - rotating ball screw nut both sides is best
So yes, if you dont go bigger than 2500mm on one axis it could be all ball screw machine which simply put is much better than any other option.


-dedicated THC is a must, i dont know whats new this year, but last year Neuron was best here in EU. It controls directly your Z axis and has all the necessary functions, like pause at corners and so on. I have one but not the time to make the plasma table. Avoid cheap THC which are not dedicated/ can not control axis directly/

-even cheap servos with 2500 encoders have enough resolution at 1:1 at one revolution 1610 screw will move 10mm so 2500/10=250 ppr so 1mm/250=0.004mm resolution at speeds 30m/min, which is really fast
depends on design probably 200W or 400W servos for the machine. I will point you from where to buy cheapest in internet.

- I don't like water bed machines. Too much hassle if not a heavy production . When i make my plasma cutter it will be air, sucked and vented into the table

Most importantly- don't rush buying until you have completed the design. If you are lazy or don't have time to design, search for designs to buy, then show us so we could help you choose. I do also bespoke designs these days. Post a job request in relevant forum section . Dean and maybe others make custom machines.


So as you see, there are options. I for once was very busy today and just sat down to respond you but was amazed at the development of your thread. So lets take life easy and see what we can do here.


If machine is meant small size, there are other options. Thats why you were pointed to read build logs. There are modular designs with elements from china, that are quite suitable for 1x1m machine.


Hope that helps