first off let me intro myself.i,ve only been on here for alittle over a week.i,ve sure done alot of reading tho and i think i,ve learned alot.i like to build sawmill/logging equipment as a hobby and i wouldn,t mind turning it into a business one day.
i,am been intrested in a cnc torch cutter for awhile now so,i,ve read most of the info on them.. i have a question tho.
i,ve seen gears,timing belts and roller chain used to move the xyz axis on cutters. in your folks opinions whats the best way to go?? i,de be worryed about using rubber belts around a 0/a torch but,i see it,s used and liked.i,de wonder about roller chain because of it stretching and i wouldn,t have a clue what pitch gear/rack to use and the best way to set it up so,it didn,t get slag in the teeth.
i,ve been thinking of using timing belts to move my x axis,chain for the y axis and a ball screw for z.i have a screw now and i,am thinking y would get the most heat so i,de use a chain drive for that.
i,de like a table atleast big enough to hold a 4x4 sheet of steel if not 4x8.

delbert

First off, let me welcome you to CncZone. There is a wealth of knowledge here available for the taking.

I have used rubber belting on my machine, but only for the gear reduction from the motors. I did not use belts for the full drive mechanism.
I did at one time use chain, which worked well. It doesn't stretch as much as you would think, as it is not under that much tension nor does it move at high speeds.

I wouldn't recommend using belts as your primary means of movement, reasons much like you have already found. I will say that the belts that I use for my gear reduction are at least a foot away from the plasma torch (and oxyfuel torch when I had it) at all times, and don't really see any heat or sparks.

I wound up using spur gear and rack as my main means of power transmission, but chain would serve you well too. I would stay away from ballscrews except perhaps on Z. The little travel and relatively slow speeds needed by Z would allow for ballscrews to be used there.

MASS:thanks for the welcome..your right about all the great info.i just love the web for all the info thats on it.i,ve always felt it,s not what you know but,who you know.a person can,t know everything but,if you can talk to alot of people you can find the answers you need. and the web allows that pretty easy.
when,i build my cnc torch i,ll either use chain or belt for the x axis.i saw a chain y axis i liked alot so,i think i,ll use that..and like you said z don,t need to do much so i,ll use the screw i have.
i,ve seen belts and chain used as a loop or a single length..i,am thinking single length with idle rollers to keep the chain and or belt on the drive sprocket.

delbert