Messages

11

General Mach Discussion / THC-300

« on: July 25, 2008, 10:26:16 AM »

Did initial setup on my THC-300.  Fault light is on and has never gone out.  Also unable to get ark OK LED.  Applied 12 VDC to ark OK terminals as per instructions and still nothing.  When plasma is running manually, I can see a voltage on the readout, but because no ARK OK signal, machine starts torch, waits for signal, doesn't get one and shuts down the torch.  Have tried adjusting ark ok sensitivity pot and no luck.  Any body have any thoughts ??

12

General Mach Discussion / Re: Having difficulty with torch heigth set-up

« on: July 15, 2008, 11:24:19 AM »

Here is the first part of the program I was using

G0 Z2.0
X8.4762 Y4.3641
Z0.25
G28.1 Z0.12
G92 Z0.0
G00 Z0.000
G92 Z2.00
G00 X8.4762 Y4.3641 Z0.25
M03
G04 P0.25
GO1 F120
X7.9968 Y5.2417 Z0.625 F100
G03 X7.9969 Y5.2417 I2.7551 J0.000
M05
G0 Z2.0

FYI - Sheetcam settings - pierce height 0.25, cut height 0.625
Mach settings - switch travel 0.2, pierce height 0.25, initial cut height 0.63

Is there a setting in the post processor that has to be changed for the switch offset in the floating Z ?

13

General Mach Discussion / Having difficulty with torch heigth set-up

« on: July 14, 2008, 01:05:52 PM »

Having torch height issues.  When I run a program, floating z axis moves down to surface, zero's and moves back to 2" rapid travel depth.  Goes to start of cut, sets to plunge depth, then transitions to cut depth.  However the floating z is .2" away from its stop - torch head is .2" too deep.  I have set the switch travel, pierce depth, and cut depth  in mach and the pierce height and cut height in sheetcam. Anybody have any thoughts as to what is happening here ?

14

General Mach Discussion / Z axis homing for plasma setup

« on: June 03, 2008, 05:05:05 PM »

Somewhat confused on the z axis homing setup for a plasma gantry.  Currently I have the z axis homing at the top (max torch to table height).  I plan to use a THC-300 unit with the torch.  I am aware that I need a spring loaded switch to define top of material.  Does this switch become the z home signal or can I still use the home signal at the top and input the material top through another input in mach ?  I have noticed that with my current setup, whenever sheetcam puts in z movements, the motor wants to drive farther up past home and sheetcam won't allow a negative value to be input for the torch height.

Thanks guys.

15

General Mach Discussion / Re: Steppers very choppy and slow problem

« on: May 14, 2008, 11:19:46 AM »

Thanks for the help guys.  The setup was the problem.  PC wasn't giving a stable waveform... Pulses at 25 KHz would start at 30 + K then drop to 300 and 500.
Optimizing the PC with the Standard PC configuration fixed the problem.

16

General Mach Discussion / Steppers very choppy and slow problem

« on: May 09, 2008, 11:50:26 AM »

Hello, first post, first problem.  I am working on a plasma table.  Last night tried the steppers out on the bench for the first time.  When I switch to JOG mode and activate, steppers move in the correct direction, but they are very choppy, turning at less than 10 rpm and it didn't seem to matter what settings I adjusted in the motor config screen.  Ports and pin settings are correct, breakout board LED's are lighting when they should.  My motor supplier suggested a problem with Mach 2 plasma and windows 2000.  Suggested running XP and reloading Mach.  I suspect I've missed something in the proper motor configuration. Currently set at 3200 steps/rev Any suggestions would sure help.