Messages

4391

General Mach Discussion / Re: laser setings

« on: November 15, 2012, 10:29:13 AM »

I not sure that I fully understand your questions so I do not know if this is of any help or not.

The Z axis direction pin toggles Hi (+5Volts, or thereabouts) when the Z axis is moved in one direction and stays at that level until the Z axis is moved in the opposite direction when it returns to Low (0 Volts, or thereabouts) and stays at this level until the Z axis is moved in the opposite direction again. This signal can be used to turn the laser on / off but it does not, on it’s own, allow for variable laser power control, just on / off.

The digital trigger is probably not the best way to proceed but it can be turned on and off within Cypress Enable with the commands ActivateSignal(OUTPUT0) / DeActivateSignal(OUTPUT0) as it is essentially OUTPUT#0 and is the Digitize Output.

Tweakie.

4392

General Mach Discussion / Re: laser setings

« on: November 15, 2012, 06:02:06 AM »

Probably the easiest way to 'software control' laser output power settings is by using the Mach3 PWM signal (0 to 100%) controlled by the spindle speed S**** commands within your GCode.
This method does, however, have it’s limitations and by experimentation it has been found that a ‘stand-alone’ PWM generator controlled by Step and Direction signals and configured as a forth axis can work a whole lot better.

In addition you would also require a simple circuit to convert the 0 to 100% PWM to 0 to 5 Volts (or whatever voltage you require for your laser PSU).

What 'type' and what 'output power' laser are you using ??

Tweakie.

4393

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: November 15, 2012, 05:01:46 AM »

HEY Tweaks, Can you track and shoot down ICBM's yet ?

You are having WAY too much fun.

(;-)TP

Hi Terry,

Given the distance and thus small angles involved I am sure Mach3 could handle the task but I think I would need a Damn Great Big Laser.  

Tweakie.

4394

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: November 15, 2012, 01:54:16 AM »

Hi Bartabac,

I am pleased that you have sorted the PWM issue. Thanks for posting the link showing your machines and work.

Tweakie.

4395

General Mach Discussion / Re: New people welcome !! Come in here and introduce your self!

« on: November 14, 2012, 08:46:52 AM »

Welcome to the forum Steve.

We could do with input based on your experience - then we all learn together. 

Tweakie.

4396

General Mach Discussion / Re: is this possible with mach 3?

« on: November 14, 2012, 08:03:07 AM »

I gave this a bit of thought and came up with a method (which needs refining) and posted my findings here http://www.machsupport.com/forum/index.php/topic,22932.0.html#new

Tweakie.

4397

Show"N"Tell ( What you have made with your CNC machine.) / Isolation Routing PCB's and Local System Rotate.

« on: November 14, 2012, 07:55:50 AM »

When Isolation Routing double sided PCB’s I drill two holes in the PCB blank (one is the datum and one the reference) to locate the work on two pins in the spoil board on the machine. This method enables good location of the tracks when machining each side and also for hole drilling etc. (always using the same datum point for X zero /  Y zero).

After reading this post and watching the video http://www.machsupport.com/forum/index.php/topic,22555.0.html  I thought I would try visual location of the datum and reference holes (using my cross hair pointer) and use ‘Local System Rotate’ just to see if it was an easier method.

Then using 3 CB buttons (at the bottom of my Mach screen) it is as easy as ABC. Well it’s almost that easy. 
Obviously this was only experimental so it is bit of a ‘quick & dirty’ solution and it needs work to tidy up the user interface side of things but it works.

Basically…

Button A turns on the cross hair pointer, sets slow jogging and brings up the status message ‘Locate Datum then click Button B’

Button B resets X and Y axis DRO’s to zero and brings up the status message ‘Locate Reference then click Button C’

Button C is where the calculation takes place – the current X and Y axis position (reference) is used to calculate ArcTan of the angle which is then used to set the Local System Rotate. The offset between the cross hair pointer position and the spindle position is factored in and the X and Y axis moved to bring the spindle to the datum position. Jog speed is reset to normal etc. and the status message ‘Complete’ is displayed.

As it turns out this method works very well and in operation is an equivalent to the system used in the aforementioned video. It can handle any rotation or position of the work (within + / - 90 degrees).
Although the accuracy I achieved is acceptable it could definitely be much improved by using a webcam for the hole location and Klaus’s video window (camera plugin). http://www.kd-dietz.com/klausphp/pages/ger/plugins/webcam/description/wcam_description.html

It is not a quicker method than my existing system of using the two dowel pins but it may have advantages with odd shaped circuit boards and possibly alteration of existing boards so definitely warrants further investigation.

My next step – fit a webcam to the Z axis.   

A short video of the result  http://tweakie.byethost10.com/rotate1.wmv

Tweakie.

4398

General Mach Discussion / Re: The PC is stuck after running few thousands lines of Code

« on: November 13, 2012, 05:53:48 AM »

Sorry, it's not much help really but my best advise would be to try a different PC with more RAM pref. >1GB (again with separate video card) or perhaps add more RAM to your existing setup.

Tweakie.

4399

Show"N"Tell ( Your Machines) / Re: The Laser Project.

« on: November 13, 2012, 03:49:59 AM »

Something that made me smile…

This guy obviously thought it would be fun to laser engrave the sausages !!.

After the fire this was the mess he had to deal with.

Tweakie.

4400

General Mach Discussion / Re: The PC is stuck after running few thousands lines of Code

« on: November 13, 2012, 02:25:45 AM »

Do you get an error message in the status line when the system freezes ??

(I regularly run programs with in excess of 360,000 lines of code without any problems so I suspect your problem is related to your PC rather than Mach3).

Tweakie.