Messages

1

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 23, 2009, 01:17:29 PM »

Mxx somewhere in the program changes output state of pin X from LOW to HIGH. I'm holding the Mach3 via LPT. What will happens with the pin X output level? Will go back to LOW or will stay HIGH as I ordered with Mxx?

Modal code for "coolant" for example, but this is just for example...

2

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 23, 2009, 12:36:51 PM »

I forget to try, will ask. I hope, in HOLD position, pins state changed by modal codes don't reverse, isn't it? Not fatal, but better is to stay in place...

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General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 23, 2009, 12:32:21 PM »

Ask the producer... Don't tell me the answer. I know. Every producer does THE BEST, doesn't change anything because of "support", because of lot of PCB's sold and ready for sale .... because they are doing for money
But, doesn't matter. In any case ask the producer... BTW, to be objective in your questions, can you add somewhere a big size photo of the solder and component side of the PCB. I want to take a look about architecture. 169 eur without delivery just to take a look is out of mind. After that we can discuss for what exactly you have paid and how to do it usable...

4

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 23, 2009, 08:36:08 AM »

Just tested Konrad's solution. Works pretty fine! Stops after complete the step, next step pulse comes after recovery, no fluctuation...
Very useable for servo drivers with "not in place yet" output which are driving big tables... And for my strange needs is useable too.

10X Konrad!

5

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 22, 2009, 06:07:04 PM »

How to measure is another question. In any case the signal is binary. Ready/ NOT Ready. Doesn't matter what this means relative to exact tool, motor or something more. Enough is to await until condition is normalized. Anyone can use it as wants. Just should to test, is solution explained by Konrad covers this. This feature can be used to hold the machine on the night with switch key too. End of working time, turn the key to hold, go to the home. On the next morning just turn the key to GO and go ahead

Funny and usable ...

6

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 22, 2009, 05:01:05 PM »

Konrad, I'm so happy you touched my sick theme from few months. Here is no spindle at all. But... almost all adequate CAM software hearing mill knows rotate tool. Especially checked SolidCAM. Next step to take a look to mastercam. In any case I'll cheat the software, but this is slow solution.

The described behavior has a lot of application. BTW if the stepper drivers are smart and checks the current in windings they will know is the step actually goes or not. Hold the step with the trigger until it done (some timeout, possible to done never) logic AND from all steppers and HOLD until all rest steps are present will prepare closed loop steppers. For servos situation is bit different, but if one good guy has understood what I have talked, soon servo drivers will have two different pulse dependable closed loop controls. Unfortunately, for now I can't explain more about this feature, because I don't know will he does this or not.


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Hood, no buttons. This will be absolutely automatic solution. How often and how many times will present the "not ready" condition knows no one. Stupid is to stay near the machine to wait if this present or not. Also, temperature depends from what part of the tool is in use right now. High temperature will compensate with low heating PWM, low one ... only with no movement until it normalized. Temperature is provisional in this explanation. Every condition which you want and can resolve is suitable.


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Good is to know for missing deceleration. Important is to know after recovering machine starts on the same place with the rest of steps to done program line.

7

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 22, 2009, 03:55:12 PM »

Tool is profile molded hot wire, laser or something similar, which may be ready or not ready in exact time. If this is laser, only happens not cut or bad cut. Should revert the program, second time in the same way, worst cut and more and more. If this is molded hot wire and from some case it isn't enough "hot" the shape will be deformed and all next process will be for nothing. Material will be for garbage too.

With another words. Any pulse which comes from the mach3 to the drivers should be send after checking the tool situation. Situation is self recovered, so just is enough to await permission to move.

And one more modification in my post. Not necessary to decelerate the motors. In any case between two pulses software has no care about next step to limit current or something like this. I'm talking about steppers. So, inertia after the step will be cut from the stepper drivers. They are enabled and all is fine. Just to await some time and go again. Now, acceleration after this hold situation is discussable, but we talking about a level few higher which mach3 covers...

8

General Mach Discussion / Re: HOLD machine via LPT pin?

« on: October 22, 2009, 03:29:46 PM »

Thank you Konrad. This should do the job. Tomorrow will try it and write a report.
Software stop is enough if works as described. The tool will be "almost" ready for a small period of time until motion stops.


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Oppps. Losing position is not good. Anyway, tomorrow will try and will ask about OEM trgiger how to if is necessary.

9

General Mach Discussion / HOLD machine via LPT pin?

« on: October 22, 2009, 12:13:37 PM »

Hi!
Tried to do search, but many possibilities to write the question gives none results.

So, in my design, tool is not always ready to do it's job. I know when it is ready or not and I have a swtich output (OC, relay doesn't matter in this case). How I can hold the machine in exactly current position until the tool be ready? I mean, not before next line, just right now. This should be done via input LPT pin. eStop doesn't suits of course.

Something ready for use?

10

General Mach Discussion / Re: Tangental Cutter problem!

« on: September 17, 2009, 03:26:42 AM »

Because I have investigated A-axis behavior a lot of time, I'll try to share my knowledge.
1. Rotate is done every time with rapid feed ratio. This is not good.
2. Mach 3 has no way to know what you want to do. So, you should up the knife before fast moves (G0).
3. G1 move uses tangential control, so knife direction will be decided before linear interpolation.
4. + and - rotates in different directions, but +0 and -0 in absolute coordinates always are +. This is very bad.

So, IMHO you should up the knife, move with G0 to desired position (will not rotate) and do linear interpolation X,Y with very small Z down in the same line. Because rotate will done with rapid feed, position will be exact before cutting. Also, this give smooth start of cutting. Of course, you should compensate in NC file all this.
Probably, this is the possible solution with the Mach 3 current behavior. If your knife is center based to Z-axis, forget for A0 position when the knife is into the material. You will produce holes in some situations.

This is my opinion, and probably I'm on a wrong way at all...