Topics

101

General Mach Discussion / Look-ahead settings...

« on: March 19, 2014, 08:57:47 AM »

Can anyone advise re the setting of look-ahead.

I am having issues on a plasma cutter running small 20mm circles at around 3700mm/min and there is a pronounced flat on one side, I have been advised to up the look-ahead settings but have no idea what to?

I am running in CV mode as far as I know.

Thanks

Dave

102

General Mach Discussion / What has gone wrong????

« on: March 06, 2014, 10:23:06 AM »

Ok so I have been eagerly awaiting the delivery of my new plasma torch, while waiting I have been extensively testing and debugging my new DIY cnc table and it was all going very nicely.

The torch came this morning so i moved the table into my test area, connected up the ground clamp and powered the system up.

All went ok, placed a bit of test metal on the table, moved to take a test fire and triggered a quick pierce signal, no cut just a quick pierce.

That went ok so i went to move the torch back to start position for a cut test, the torch would not move so i pressed the estop and restarted, z axis started moving and partial x axis but not Y.

Killed the plasma supply and reloaded Mach.

Now it was jumping about randomly as i turned the MPG knob on the pendant and kept throwing "e-stop requested" errors.

Thinking it might be my cheapo crap pendant, i unplugged it, turned off "run macro-pump" and disabled support for modbus/mpg.

Then i reloaded Mach and tried again, now it sort of moves but the DRO's are moving like 20mm for every mm moved.

Pressing home all, would bring the axes to home but then back off at 1% speed or very slow at least.

It would also still throw the e-stop requested errors.



Now, having spent a lot of effort hardening the table against RF, I cant believe I have fried it with a two second pierce?
No other PC's in the area showed any sign of problem and there was no radio interference.
This was just a quick pierce at half power.

Any suggestions at all?
I'm desperate.

103

General Mach Discussion / Soft limits info please...

« on: February 17, 2014, 04:45:10 AM »

Having just got my hand jog wheel working nicely (thanks Hood) I have uncovered an issue that i need help with

The first cycle runs perfectly - jog to position, reset origin, run code.

this however leaves the z-axis at zero work co-ords but -50 machine co-ords.

the next time i issue a start cycle i get soft limit warning on Z axis as i am trying to probe to -65mm from machine zero but it obviously wont let me as that would be way beyond machine z limit max.

is there a way round this?

104

General Mach Discussion / Modbus / MPG help...

« on: February 14, 2014, 08:22:42 AM »

As a bit of entertainment I ordered a super cheap handwheel pendant off ebay to connect up to my plasma table (which is still being assembled  ), surprisingly it arrived today after only two weeks.

Anyway, got it set up and seems to work apart from one bit which makes no sense and i'm not sure if it's the super cheap pendant or a setting I need to tweak.

When I jog the head to where i want to start, I presumed I press the button marked "Origin" also labelled as "Start Point" in the chinglish manual and then press "Start"?

But when I press "Origin" it presses the Mach3 "To Go" button on screen and does not set start coordinates so when i press "Start" it starts at machine zero.

Is this fixable or should i stop messing about and return it for refund?

105

General Mach Discussion / Feed hold, am i using it correctly?

« on: February 10, 2014, 10:10:59 AM »

I'm trying to figure out how to temporarily stop a program running on my plasma table.

I know all about the big red button but that's not ideal if i just need to pull a tip-up out the way etc.

I have tried the Feed-Hold (space bar) feature and it does stop it running but as soon as i hit cycle start to get going again, it just raises the Z-axis into the soft-limit and all action stops.

Am i thinking of the correct method or can you not simply hold a program.

I have my z-limit at the top and I'm using soft-limits as well and G31 for the height probe on my floating head.

Thanks

106

General Mach Discussion / CV Control Help For Beginners....

« on: February 07, 2014, 08:29:16 AM »

Messing about with my plasma table this morning (no torch yet, just felt tip pen) and i thought as it was a plasma i would flip the "Plasma Mode" checkbox to on?

Anyway as the tests got harder, I noticed it was running very jerky on curves and was not happy at all so i have just flipped "Plasma Mode" off again and all is well again.

Could someone explain what is happening here and what, if anything should be in the "CV Dist Tol" box and "Stop CV on Angles >" box?

Just want to make sure I have every option  I should have ticked and set right while im learning


Thanks

107

General Mach Discussion / Mach3 & safety devices...

« on: February 05, 2014, 03:46:02 AM »

Apart from the charge pump (which my BOB does not recognise), is there any signal that mach gives out via the BOB that would indicate it is loaded and ready for reset??

Just trying to figure out a decent safety control plan.

108

General Mach Discussion / Auto Z setting, macro help....

« on: February 03, 2014, 03:35:42 PM »

Can someone tell me what this code would do if placed at the start of the M3 command....

DoOEMButton (1010) 'reset z DRO
Code "G4 P1" 'wait
Code "G31 Z-100 F250" 'probe surface
While isMoving()
Wend
ZprobePos = GetVar(2002) 'get contact point
Code "G0 Z" &ZprobePos 'return to point to remove overshoot
While IsMoving()
Wend
DoOEMButton (1010) 'reset z DRO
Code "G0 Z20" 'remove floating head travel
DoOEMButton (1010) 'reset the z DRO

Would that not probe the surface and leave my Z DRO at zero ready for the M3 command to complete?

This is all theory but I do write VB programs in my day job and it's very similar, what I want is for mach to reference the material surface at the start of EVERY plasma pierce/cut.

Any ideas

Thanks

109

General Mach Discussion / Floating torch head, how?

« on: January 31, 2014, 01:26:12 PM »

Looking ahead with my plasma table build, I'm trying to find out how a floating z head works with mach3?

If I understand it correctly, there is a switch on the head slide that holds the torch, when the cycle is started, the head drops until the switch opens, then raises until it closes, then raises a preset amount more and zeroes the Z DRO. The cut then starts as normal.

Is that correct?

If so, where is the input fed into mach software and does it actually reset the Z DRO??

Any tips appreciated.

110

General Mach Discussion / Help with soft limits please...

« on: January 30, 2014, 02:23:51 PM »

Now I've finally got my table running, no plasma yet, just setting up, I am trying to figure out soft limits in mach as it's a bit to easy to jog into the limit switches.

I have an envelope of 650x650mm so I set my minimums to 0 & 0 and my maximums to 650 with a 10mm slow zone but it didn't seem to work, have I set the soft limits correctly??

Also, when I tried to re-run a previously working test code, I get a G54 error.

This is all new to me so I thought it best to ask.

Also, on a plasma table, is Z0 torch up or torch down?
My preference is for Z0 to be with the tip touching the machine table.