hi frequency start is going to be a bitch. what if the estop is disabled. by that i mean in ports and pins give it a setting of parralel port 0  or make it emulated?

Maybe some caps between your E-Stop/Limit inputs and Gnd would help, usually 0.1uF is whats used I  think.
Hood

I will try these suggestions tonight. In the meantime I am trying to see if I can trade in this machine for one without the HF start. Thanks all.

SOMEWHERE on the web someone conquered the chines HF start noise  problem. He had posted the info on HOW TO.  I think it was on the  PlasmaSPider site.

Just a thought. (;-) TP

CLoser than I thought, Here is the link, Good luck with it.

http://www.machsupport.com/forum/index.php/topic,20076.0.html

(;-)TP

Wow BR549 that is a great find. I have printed it and will pour over the details tonight. Thanks much I will try and make these changes and let everyone know how it worked. Thanks much!

Plasma cutting table and control electronics shouldn't have electrical contact in no way. Ground your your cutting table wery well. Electrically isolate your switches,motors etc. And use coaxial cable. Ground your coaxial cable and control electronics box together on a seperate ground.