Messages

2401

General Mach Discussion / Re: Where are the plasma THC settings

« on: May 04, 2014, 12:40:50 PM »

I think you'll find the THC min speed is the point where anti dive kicks in, I.e. The minimum % of set cut speed that it starts anti dive, I have mine at 90% so I think that if speed drops to below 90% of my set feedrate it will not dive the torch.

Small holes I am still learning but, if you set a lower feedrate in gcode, it will not allow anti dive to work because the feedrate is now lower. What I am doing is to split my small holes out in cam and apply a manual THC off command before it cuts and THC on after, before going back to full cut speed, this seems to work but...

I have also just found that by tuning my speed and acceleration figures on the table, I don't need to slow down manually apart from small holes in thicker material which I do as described above, I can do a 10mm hole in 5mm plate at normal feed and let antidive deal with it.

Yes, I think if you change cut parameters a lot, I think you may need to up the THC rate a bit, possibly.

2402

General Mach Discussion / Re: Where are the plasma THC settings

« on: May 04, 2014, 10:30:22 AM »

Is there a box labelled Anti dive % ?

That is the limit before anti dive kicks in, mine is set at 90%

There is a box labelled Rate, that is the % of z feed rate that THC uses! there is no acceleration or deceleration here, my rate is 8%.
To alter the min and max and rate levels, click in the box, type the new value and press enter, it does not work unless you press enter.

Mine is  set at -5mm and +5mm, seems ok but my table is a small one.

2403

General Mach Discussion / Re: reset Button somtimes Hits out

« on: May 04, 2014, 04:20:08 AM »

Are you meaning the reset button on the screen starts flashing red at random times when the machine is idle?

Could be a loose wire in the e-stop circuit or something interfering etc, does it never do it when running?

2404

General Mach Discussion / Re: What happens when...

« on: May 02, 2014, 02:07:27 PM »

Ok thanks, pretty much what I guessed would occur.

Yes it's duty cycle, I'm limited on power and only have a small unit, I am still learning nesting in sheetcam and have successfully incorporated wait commands in my files, naturally they need to be as far apart as possible without tripping duty cycle limits.

I think everything is coming together nicely now


Dave

2405

General Mach Discussion / What happens when...

« on: May 01, 2014, 10:47:19 AM »

The "arc ok" signal stops mid-cut on a plasma?

This could happen on my system due to duty cycle, the plasma unit will shut off if its reached its limit, I guess this would wreck the part??

Would cycle-start get it going again or is an abort-job issue?

Thanks

2406

General Mach Discussion / Re: Limit Switches

« on: April 30, 2014, 07:58:07 AM »

Ok thats good.

If you press tab to get jog control up, then press the up arrow on the keyboard, does the the gantry move away from zero/home position i.e does it move in a positive direction??

2407

General Mach Discussion / Re: Limit Switches

« on: April 30, 2014, 07:32:07 AM »

Hmmm, what does the G-code say?

Does it look logical?

2408

General Mach Discussion / Re: Limit Switches

« on: April 30, 2014, 06:45:38 AM »

If it is homing in the right direction - bottom left corner, then flipping the reverse flag will likely change this. there is another box for homing direction that will likely need doing as well.

Once it is jogging and homing correctly then move on.

2409

General Mach Discussion / Re: Limit Switches

« on: April 30, 2014, 06:44:17 AM »

In the config screens, possibly ports & pins, there is an option to reverse direction, try flipping that on or off.

I am not in front of Mach at present so I am guessing, but it is there.

Have you got limit switches at both ends of the X & Y axes?

2410

General Mach Discussion / Re: Odd glitch in movement?

« on: April 29, 2014, 04:53:21 AM »

Yes, i think so 

Anyway, I just squeezed in a little play time and ran the dumbell with THC off and no change so as I suspected, my ripple effects are all machine related, at least i know now.

I tried dropping the acc to 850, no change so i will leave it there for now.

Then I tried the file for the picture attached, this is the most detailed I have tried yet and was met with total success, the shape matches the file, it has some surprisingly fine detail in it and apart from the metal being some galvanised crap, is just about perfect.

There is some dross but look at it and falls off so i'm not worried about trying to get rid of that, looking at the way the machine was whipping around it, I really dont think more speed is possible so dross is a thing that I live with I guess?