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Offline Hood

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Re: Physical buttons for plasma
« Reply #140 on: January 28, 2016, 03:39:27 AM »
The CSMIO has a M31 macro for probing which basically is the same as G31 in Mach but all done internally in the CSMIO, if it is anything like their M84 macro it will be the dogs danglers :)

Going to test out the THC hooked up to the small servo motor/drive directly over the next wee while and see how it performs.
As said I am a while away from getting my table started so I might as well do some messing in the evenings at home to see how it performs.

Hood

Offline Davek0974

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Re: Physical buttons for plasma
« Reply #141 on: January 28, 2016, 06:09:59 AM »
Ah, but what I mean is this...

Set volts to say 90v because thats where you reckon it should be...
Start the cut and the THC reads 98v so tells Mach "Send the torch down.."
Mach drops the torch but as it so close to the surface the volts only reach say 94v,
The THC shouts "I want more, drop the torch again..."
Mach says whatever and this loop continues with the Z dropping but the volts not changing anymore because they can't.

Sounds spurious but on thin material with the 30A consumables its very easy to do.
Mach or the THC should see the repeated DOWN calls AND the fact that volts is NOT changing and say "I'm not allowing that anymore", maybe even lift the Z a mm or so. ;)

Found it, it does exist, its in the Mp3000 settings screen and is what CandCNC calls Tip-Saver. It (should) work if you set it  to a value that keeps the torch just off the plate, so if normal volts is 90, the tip-saver is set for 2% this means once it reaches 88.2v it will stop further downward movement. Of course you have to know what value will keep the torch off the plate but it sounds good.

I have no idea what my one is set for but I know for a fact that its not as low as 2% so will be playing with that I think.
There is also max and min volts limit which i think I have set at 200 & 50 but no idea what the actual max and min cut voltages are for the PM45??
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline BR549

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Re: Physical buttons for plasma
« Reply #142 on: January 28, 2016, 07:52:23 AM »
 Tip Saver and Anti Corner dive CAN be 2 different things (;-)  Tip Saver is when it crosses a void and senses a very quick change in Voltage based on time. It is controlled from teh THC side as that side sees teh voltage levels real time.

Anti corner dive is based on a change in Axis Velocity. It is normally run from teh Mach3 side as it KNOWS what the Velocities are.

You may want to read teh manual to verify that tip saver can do both.

Just a thought, (;-) TP

Offline Davek0974

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Re: Physical buttons for plasma
« Reply #143 on: January 28, 2016, 10:25:23 AM »
I read all the manuals - CandCNC produce more manuals than a library can handle but they are very confusing at times ;)

I used google to research the Anti-Dive as I can't find it mentioned in a manual but there is plenty info out there on the 'net.

The two seem to do totally different things so running both anti-dive AND tip-saver is Ok.

I will check my settings for each one and have a play, I think tip-saver is the important one as my table does not slow much on corners unless i tell it to and thats not the same thing so i'm ok with that.
Bridgeport Mill, Mach3 V062, CSMIO-IP/A controller, AC Servo Drives

Offline Hood

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Re: Physical buttons for plasma
« Reply #144 on: January 28, 2016, 07:15:40 PM »
Well I hooked up the small servo to its drive and set up the two inputs as Presets. Set the RPM at 4000 and -4000 at accel and decel of 4000 revs/s/s and it worked great, instant action :)

Next step is to make up a wee circuit so I can feed the Torch Up/Down outputs from the THC into the drive, can then put a voltage to the divider board and vary that slightly and see how the motor reacts to the THC signals.

Hood

Offline Chaoticone

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Re: Physical buttons for plasma
« Reply #145 on: January 28, 2016, 08:55:26 PM »
Well I hooked up the small servo to its drive and set up the two inputs as Presets. Set the RPM at 4000 and -4000 at accel and decel of 4000 revs/s/s and it worked great, instant action :)


 :)
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Offline stirling

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Re: Physical buttons for plasma
« Reply #146 on: January 29, 2016, 06:41:41 AM »
Hi Hood - looking good. Remember what I said earlier though. It depends entirely on your THC, but I reckon you're going to end up capping that speed big time. Maybe 100 rpm or so depending on what you use for a lead.

I must have missed it somewhere but what's the idea behind having a slide on a slide for Z with an extra motor as opposed to just driving Z?

Ian

Offline BR549

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Re: Physical buttons for plasma
« Reply #147 on: January 29, 2016, 09:30:45 AM »
I am also watching to see where he goes with this (;-) I can think of several ways to do this BUT I want to see where Hood ends up. Might learn something new. (;-)

Unless you are doing high speed corrugated cutting a regular setup works just fine 99% of the time.

(;-) TP

« Last Edit: January 29, 2016, 09:32:43 AM by BR549 »
Re: Physical buttons for plasma
« Reply #148 on: January 29, 2016, 09:34:29 AM »
I think the two z axis were to have a slower positioning axis (to touch off) and a high speed low inertia high acceleration THC axis..

Probably back on page 5... ;)
Rob

Albert Einstein ― “If you can't explain it to a six year old, you don't understand it yourself.”

Offline BR549

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Re: Physical buttons for plasma
« Reply #149 on: January 29, 2016, 11:45:24 AM »
You an do that with 1 Z axis. As a plasma you do NOT need a supper heavy duty Strong torch mount as you would use with a router. You just use a very light weight low inertia Z assembly. You can Position at any speed and still have HIGH speed for the THC control.

BUT As Ian mentioned it WILL depend on teh THC being able to keep up with the Z moves. With a lot of the current THC units that use Mach3 they are slow enough that you can actually outrun teh THC and get Occilations in teh Z control from overshoot. AND that is using a small stepper setup.

(;-) TP