Messages

1

General Mach Discussion / Re: thc help

« on: February 08, 2007, 04:09:37 PM »

what about our version of mach.  should we update to the new one or stay with what we have.  thanks for the info.

2

General Mach Discussion / thc help

« on: February 07, 2007, 09:35:38 PM »

we are running mach3 1.84 version on a plasma/router table using a mp1000 thc.  i understand a little of the thc function on thin metal, but if my feedrate in my plasma manufactures chart says a specific height with a certain amperage, tip volts, speed, and pierce height, will cut x inch metal, then why should i run thc if i could just create the right height in my gcode.  i wouldn't think anything over 3/16 wouldn't move that much.  with that being said, can i turn thc off and still run parts.  it seems when we do that our torch will starting moving before it fires.  also, what exactly does the thc dro mean.  i see it moving up or down in numbers but what is it doing for the torch.  table is grounded with ground rod also.  also would it be recommended for us to download the newest version of mach3.  i read something on here with someone saying to change from 45khz to 25khz with a similar prob.  is this the kernel speed.  if so ours is at 35khz.  would this help.  hope this isn't another one of these "we've already answered this one" topics.  please help.
thanks

3

General Mach Discussion / Re: help please. destruction next step.

« on: August 28, 2006, 07:05:45 AM »

that is what we were thinking also is the thc has a prob.  going to contact the maker today.  thanks for your response.  what is weird also is if we turn thc off, the torch still may not be exactly .06 off the material if that is what we set as a cut height.  i don't know if it is in mach3 or something else.  like i said, we have had numerous problems with this thing since we have owned it.  just trying to eliminate one thing at a time.

4

General Mach Discussion / Re: help please. destruction next step.

« on: August 26, 2006, 07:58:35 AM »

Hello,
Hope i'm not boring you with thisone, but could it probably be that the up/down signals are inverted and-or switched?
I'm not really shure about THC sequence, because i've no experience with it (but similar capacitive height control on laser machining), but this is what i think.
As long as your tHC-unit does not report stable arc with THC on signal, your height control is inactiv. If this signal goes active, THC is enabled. If your thc-signals are crossed, and the active state is inverted(input signals tab, 'active low' setting enabled or disabled), then your system might correctly detect sheet contact, but the control would do the opposite of what is needed.
Hope this helps...
Kris.

how do i figure out  if this is switched.  it was working fine a week ago. 

5

General Mach Discussion / Re: help please. destruction next step.

« on: August 26, 2006, 07:57:17 AM »

i am not sure.  it is a dynacnc machine.  how do i find out.

6

General Mach Discussion / help please. destruction next step.

« on: August 25, 2006, 10:51:23 PM »

probably a dumb question but here goes.  we have a dynacnc plasma router table.  we are just using plasma.  bobcad is our design program, sheetcam, and mach 3 runs our machine.  if we set a cut height at lets say .06 in sheetcam, when the g code starts running we can watch our z axis and it will zero out when torch touches metal and then go to pierce height and then pierce delay, but then start running and z will move to as high as .400 and never go lower.  we will let it run for a sec and then stop it to measure to see and it is way above .06.  thc is on while running.  now, we can go to sheetcam, put .180 as a cut height and load g code in mach, leave thc off and machine runs at .06.  we are cutting 1/8" steel.  what is the deal.  is this normal.  why will machine not run at desired cut height.  help please.  we have had nothing but problems from this machine.  next step is to throw machine off cliff   any help will be greatly appreciated.
thanks