Messages

2481

General Mach Discussion / Re: THC Codes upset corners???

« on: April 09, 2014, 02:18:21 PM »

Lol 

One good thing I do have going is a dual-purpose z height probe, first position is probe height, 3mm more is a limit switch so if it did ram the torch, the most that could happen is an e-stop

I have a lot to learn methinks, at least it's all playing nicely together now, the hypertherm was a revelation and solved a massive amount of grief with HF issues.

The hard part is learning blind, it would be so much easier to just have someone there to say "do this" or "do that" etc, that is why I have so many odd questions

2482

General Mach Discussion / Re: THC Codes upset corners???

« on: April 09, 2014, 10:54:27 AM »

Having just got the thing running, I now see what happens or at least can happen. I am deliberately cutting with the metal tilted so I can see what goes on, if it started at a high point and couldn't go lower then yes - fail.

I now have -3 min and 5 max, but i think more would be ok although a warpage of 5 to -3 is a pretty bent plate

Trying to get it dialled in now, getting top dross at present but at least its running and not crashing the torch or winding it way up high (any more )

I think I can see what it needs now.


What sort of values of hysteresis do others use, I'm not sure of the relationship between a volt or two and distance in the arc.
Currently set for +/- 4v

2483

General Mach Discussion / Re: THC Codes upset corners???

« on: April 09, 2014, 09:35:09 AM »

What i meant was that if THC Min is zero, and the torch is running say 1.2mm, a torch dive would/could NOT send the torch below THC min, i.e it can only dive as low as zero in this case.

As you said, it cannot so that answers my question and makes sense.

Thanks

2484

General Mach Discussion / Re: THC Codes upset corners???

« on: April 09, 2014, 07:14:31 AM »

If you DO get torch dive it should ONLY be at the start as it gets up to commanded feed and at the end as it slows to a stop. With good accel you shouldn't even get it then.

There is a caveat to this in that you can get dive on a kerf crossing - Mach's anti-dive won't help you there as it's purely speed dependent.

OEM 123 toggles THC on/off. Curiously labelled "Torch Enable Toggle" in the spreadsheet.

Thanks for that, making more sense now.

The start should be ok as the unit has a built in delay before its starts sending signals.

I did notice the toggle OEM but was looking for an on/off pair, it will work though.

Was i right that it can't dive below THCMin though??

2485

General Mach Discussion / Re: THC Codes upset corners???

« on: April 09, 2014, 02:37:33 AM »

I also thought it customary to program a speed reduction on small circles to say 60% ?

Surely here I would need to program in a THC off command and on again at the end as Mach has no auto-slowdown for small circles feature.

2486

General Mach Discussion / Re: THC Codes upset corners???

« on: April 09, 2014, 02:17:30 AM »

Thanks for that, this is all new to me so forgive me for asking about things that may never happen

I presume in a torch dive, it cannot dive below the minimum level set in Mach i.e. 0mm or material surface?

Is there an OEMButton code set for THC on & off, i couldn't see one in the list.




Thanks again

2487

General Mach Discussion / Re: THC Codes upset corners???

« on: April 08, 2014, 01:47:00 PM »

No idea, as I said Terry and Ian are the guys that can most likely answer your questions regarding Plasma.
Hood

Thanks Hood, I am trying but little or no response, if this were shareware I could live with it but I bought the license

 

I don't need external outputs just a way to switch Anti-dive on and off from g-code without introducing a delay which would cause issues when plasma cutting.

You appear to have the wrong end of the stick regards anti-dive. You turn it on at the beginning and leave it to do it's thing. IT turns THC on and off automatically as required by the %feed setting.

Ah, thanks, that is indeed different to what I presumed.

So what happens when sheetcam sets a reduced speed for say a circle, mach will not see a deceleration as the speed change was programmed, will the torch dive or not?

I can't fathom how it will work with a "dumb" THC like I am in the middle of fitting? It only has up and down outputs (can't use arc ok as I have no more inputs). By embedding on off codes in my g-code I could see how it might work but without that I can't.

Using edited m10/11 macro codes does not introduce a delay so that is one good thing, but if anti-dive is just on, what is left to control torch dive when anti-can't work because it's a coded speed reduction?

2488

General Mach Discussion / Re: THC Codes upset corners???

« on: April 08, 2014, 04:58:53 AM »

No idea, as I said Terry and Ian are the guys that can most likely answer your questions regarding Plasma.
Hood

Thanks Hood, I am trying but little or no response, if this were shareware I could live with it but I bought the license

2489

General Mach Discussion / Re: THC Codes upset corners???

« on: April 08, 2014, 04:01:17 AM »

If they are actual signals going out from Mach to a stand alone THC then likely M11/M10 will do what you want. You have M11 at the start of a line of the code and that sends the signal out as soon as the code starts to execute, M10 at the start will stop the signal, there is no delay as it was designed for laser firing.

Hood

If these two macros were adjusted to press OEMButtons would that introduce a delay again??

I don't need external outputs just a way to switch Anti-dive on and off from g-code without introducing a delay which would cause issues when plasma cutting.

2490

General Mach Discussion / Re: THC Codes upset corners???

« on: April 08, 2014, 02:15:42 AM »

Have I got this right?

If I set "Stop CV on Angles" to 90deg, then set set THC anti-dive limit to 90%, if I then put triangle loops on the corners of external squares it will slow down, turn on anti-dive, make the triangle loop, accelerate and turn off anti-dive?