Problem- TM3 Setup

[Feckless]

Hi there,
I recently got a TM3 and Thermaldynamics 151 and built a solid table for it. I had to make an extra bracket with an extra bearing for the gantry which greatly increased stability on the lower side of the table, however I cant seem to get the circle cutting sorted. I have very little backlash on both axis now and have been trying many combinations on the settings but they look more like eggs than circles, we are in metric land so I converted the machine settings as in the documentation but I was wondering would anyone post their settings for max feedrates, ramp speed, max conturing speeds etc. When changing materials the only settings I change are the feedrate and amps/ tips. for example 5mm mild steel 1800mm/min feed at 60Amps.
Any help would be appreciated.
Gordon

[Mike@Torchmate]

Non circular shape cutting is almost always a result of a physical backlash or slip in the motions of the table. IE a loose set screw, backlash between the gear in the gear rack, or the bushings in the motor mount bracket.

Some recommended feedrate values in metric are:

890 Start Stop Feedrate
6350 Maximum Feedrate
200 ramping rate
Direction change .001
1778 Continuous Contouring

[Feckless]

Thank You Mike,
I will go over the machine again and use the figures as a guide, if it works I got an order for 42 x 600mm discs with a 12mm central hole in 10mm plate to cut tomorrow and Saturday, Wish I'd got Hi-Def as we are getting a lot of requests for stainless, next machine in planning (bigger and a torchmate again)

[Med-Pac]

you're going to fast for hole cutting. On our tm3 we cut our holes about half the speed of the perimeter cut. I just finished cutting 7 ga A-36 plates with 1.25 holes in them to accept 1.25 rod. We have the hypertherm 1000.......7ga cutting speed is about 40-50 inches a min., we cut the holes at 20-30.

[Feckless]

just to say thanks again, worked a treat, I found play on the shaft and cam pulleys, customer delighted so are we, cut holes at 600mm/min and had THC on manual, seems to give a better cut as when the ctr falls out the thc does not drop looking for the steel which is no longer there.
Great support, thanks again
Gordon

[fenixes]

hello,

how can I do to make a small hole?, I try to make a small circle but is not perfect, is similar to an egg.
How can I do to print a point (no a circle) with the plasma??

thx

[Med-Pac]

Hello,

Here is some of our cutting on our torchmate table, we're using a hypertherm 1000 g3. If you're having issues with your hole quality; slow your speed down. I have never pushed our machine faster than 120 ipm on 18 ga material. For .250 thick mat'l: use 60 amp consumables, for hole quality 20-45 ipm, for perimeter around 60-70 ipm. arc volt setting 155-165. If your torch wants to dive into the material because you're going to slow for it to correctly sense the material. switch your controls to manual and control torch height with the pierce (only works on parts that don't warp to bad). Our tolerances on mat'l .03-.187 are +/- .015; tolerances on .25-.375 are +/- .03; tolerances on .5 and above are +/- .06

Mike