Messages

2021

General Mach Discussion / Re: Physical buttons for plasma

« on: February 04, 2016, 01:24:36 PM »

Dave,

Divot at the end, you could try using m10px and m11px to turn your torch on and off, and change your post processor to extend your torch travel a little.... So the machine motion does not slow down before the torch goes off.


Divot at the start.... Sorry you are stuck there unless you can pierce in the waste (hole centre, out of the part or art in your case.... Nice website must say)

I have spent days messing with combinations of torch off early, lead-in, lead-out, over-burn, and so on. I can get it pretty good i think but there is no online library of divots (yeah i know, it's hard to believe) to compare results with so what i get may indeed be really good or totally carp. I have many threads on many forums and no real results apart form my bog-standard go-to of 4mm perpendicular lead-in with no over-burn and 2mm arc lead-out. Trouble is with all the combinations of settings available there are thousands of things to try, most of which are useless

2022

General Mach Discussion / Re: Physical buttons for plasma

« on: February 04, 2016, 01:02:57 PM »

Dave how are you controlling THC?

Is it via mcode?.... Or what?

Hi

Yes, sort of.

Its a CandCNC MP3000-DTHC2 so has the ability to set THC via the CAM, I set everything in SheetCam - Volts, Pierce delay, THC on/off, THC delay etc.

I use Sheetcam rules to turn the THC on/off on corners but since setting my anti-dive and tip-saver i might stop this and see what happens.

The MP3000 has its own cpu and talks to Mach via the serial port, when you load a code file the settings are sent through to the THC and stored there.

I use the M10p/M11p (?) codes to turn the torch on and off and none of the THC commands cause any pauses in motion.

2023

General Mach Discussion / Re: Physical buttons for plasma

« on: February 04, 2016, 12:51:38 PM »

Now, if you could come up with a device that eliminated start and end divots, I would buy it

These are by far the most annoying part of plasma for me, seems whatever i try, and i have tried hundreds of combinations, nothing seems to get rid of them, plus it seems you need different settings for inside and outside starts/ends - total PITA


I have my Mach Anti-dive set at 95% and the CandCNC Tip-saver set at 2% they seem to play well together, still not got a reply on the CandCNC forum D'0h!

2024

General Mach Discussion / Re: Physical buttons for plasma

« on: February 04, 2016, 02:32:29 AM »

Whatever you use, i would not use motor current sensing for the IHS method, unless you cut 12mm plate all day it will buckle the sheet and give bad readings for z-zero. Since tweaking my system up with an offset switch probe and increased z motor tuning, the cuts have certainly improved and I am fairly confident it can follow pretty much any warp I will see.

I still have the floating z setup, connected to my limits chain, i would not build without  this as its a good safety feature in case of a dive, a mag-break torch holder would probably be a good replacement though, i will be wiring my z limit to the e-stop circuit soon as the limits are ignored when doing a g28.1 and if my probe switch fails it will plant the torch heavily into the sheet, there is enough torque in my stepper/screw drive that it will not stall the motor and just keeps on going! The failure point is that it rips the delrin nut out of the z-axis body which means stripping it down to replace it.

I admire your work on this though, I love R&D work, used to de plenty of it once in the day-job, only used servo's once though and that was step/direction to the servo drive and then closed-loop with encoder/resolver on the servo motor, this was a feed system for a stamping machine.

Proma did have an upgrade version of their THC and it took over direct control of the Z motor, switching back to Mach when stopped, I nearly tried it but splurged on the MP3000 instead. I managed to get the loop response times from Proma guy and it was certainly slow, ok for cutting thick stuff but I found it failed on thin sheet due to the speed needed.

2025

General Mach Discussion / Re: CNC mill has mind of it's own

« on: February 01, 2016, 03:38:51 PM »

Okay thanks for the replies I will try them all. As for a dedicated computer, that is what I'm doing. I have the Anti-virus software on the computer to help with any virus I may get with the other computer connected to my network. I like to be able to transfer files from the computer running the BobCad V27 software (which has anti-virus softeware installed) to the dedicated CNC computer. Do I need to worry about virus transferring from BobCad computer to the CNC computer? Also Hood do you mean the computer or the controllers overheating? I have cleaned out both of these but didn't look at the capacitors. However it is also something I will do anyways. Thanks for all the help I will let you know what I find out.

Pat

Is either pc on the internet??

No, then you do not need antivirus software.

If the non-cnc pc is on the 'net then i would sever the connection and use a usb drive to transfer the files.

The chances of getting a virus on a cnc pc is bugger all as they usually transfer with word files or audio/picture files etc. Virus software is a major workload on a pc, Norton being one of the worst but any is bad news.

Even the network card itself can be bad news and if not connected should be disabled in windows networking as it will constantly send out packets in search of other computers which it cant reach as its unplugged so it just sends and sends, working the cpu wastefully.

I have no idea if these points will help but ruling out basic stuff is always good i think.

2026

General Mach Discussion / Re: CNC mill has mind of it's own

« on: February 01, 2016, 02:22:11 AM »

Personally i would get rid of the antivirus and run a clean, disconnected system only.

No idea if thats the issue but antivirus is a bad idea.

2027

General Mach Discussion / Re: THC moves on the Z axis...

« on: January 31, 2016, 04:11:33 PM »

I did, I made quite a few up/downs with G00 Z5 / G00 Z30 commands from the MDI line and it always worked well, no sign of a screech.

I also used my IHS calibration routine to run repeated sequences and it always worked.

When running code it screeched maybe once every 10 or so runs, now I come to think of it, I'm fairly certain it only did it when doing a G28.1 move.

I always presumed the jog with keyboard and shift simply moved the motors towards max velocity at the stored acceleration curve??

2028

General Mach Discussion / Re: Here it is the first piezo touch probe...well that I made..

« on: January 31, 2016, 04:02:21 PM »

2029

General Mach Discussion / Re: Msgbox function...

« on: January 31, 2016, 04:01:04 PM »

Can I recommend starting a new thread? 

Does the motor screech instead of moving?

2030

General Mach Discussion / Re: THC moves on the Z axis...

« on: January 31, 2016, 08:35:23 AM »

Well, using the keyboard to bang the Z up and down I was surprised how lazy it really was!

I had 10% rate set and a max Z of 1300mm/min, Now I have 1500mm/min and upped the THC rate to 20%, It could handle 30% easily but 40% screeched and did nothing so I know I have a bit of slack still from 20 to 30%.

Now, this brings me on to a serious point that is baffling me - I have been bashing the crap out of my Z all morning, hammering it up and down with the keyboard, messing with tuning etc and it has behaved flawlessly all day apart from when being pushed too hard by my setting.

BUT, I put some code on and cut some tests and bugger me if the first time it hit a G00 Z3.8 for the pierce, it just sat and screeched, then next time it did IHS the rapid part of the G28.1 move screeched and was missed then it dropped at the slow rate all the way and carried on as normal.

This appears to be Mach3 not using the acceleration on the G00 move or the G28.1 move - is this a known bug/flaw/defect ??

I really do NOT think it is motor tuning as it has done it before and did not do it once using the keyboard to rapid the hell out of my Z axis.

Any ideas???