CNC Plasma Table Speed Calculations

[Scott V]

Just so you know Tom, my Thermal cuts at twice the height as the Hypertherm.
I use a exposed tip for most of my stuff and you need more distance.
It could have a pierce height of .190 and a cut height of .150 depending
on material/ amps/ etc.. If you doubled the cut height for piercing it would
be way too much.

[Terry G]

Torchhead,

Thats good to know about timing belts. I decided to go with the XL series of timing belts and pulleys. I'll be running a 10t to 40t combo with pulleys spaced apart 3 inches mounted in an enclosure. The output shaft will go to a 10t #35 sprocket, driving a 40t sprocket on a jackshaft. This will give a final 12:1 reduction giving me around 240 oz-in of torque at the jackshaft from my 20oz-in servos. I had some new #35 chain and a 45 tooth sprocket laying around from a chopper project I did. With a little bit of tension on the chain, there seemed to be 0 backlash. So I feel this belt / chain combo should give me a pretty tight setup.

With the THC-300 you mention you need to set the controls while you cut. In the manual it says to start your cut and adjust the torch voltage to 100V, and fine adjust the torch height to around .125. Just so I completely understand, is this something you would do at the beginning of your cut only once, or are you suppose to constantly be changing the settings during the entire cutting program. And if you were to adjust at the beginning of every cut, wouldn't you want to do this in a scrap area of your workpiece before you begin your actual cuts?

I'm asking all the questions because I am considering going with the THC-300 and using the Mach 3 software and breakout board to control my servo drivers. The manual is very good, and I understand how to hook up the entire system and get it going. Just not quite sure what to expect during the cutting process. I've subscribed and been accepted to the yahoo group, so I'll be doing some more reading on there.

Thanks.