Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: Rypper on December 15, 2006, 03:42:56 PM

Title: Edge Probing
Post by: Rypper on December 15, 2006, 03:42:56 PM
Hello,

I have now gotten my probe connected and working.
and would like to do some edge(profile) probing with Mach3.
Is there a macro or wizard available for this function.

Thanks,
Tom
Title: Re: Edge Probing
Post by: Scott on December 15, 2006, 07:34:54 PM
Looks like it's a good time to write a Wizard.  ;)  I took a look at the code behind the "Digitize" wizard, but that one appears to give a point cloud coordinates text file by probing the Z axis.  I'm not sure how you would make it probe a edge, because I think you would have to make it go around the perimeter of the object by means of a circular movement (diameter variable for resolution).  Maybe someone a bit smarter can tell us how to do a G31 probe with circular steps around an object.

The screen setup wouldn't be to hard.  ;)

Regards,
Title: Re: Edge Probing
Post by: Rypper on December 16, 2006, 08:30:57 AM
Scott,

There is a edge probing file that came with the Shopbot(if I can find it) could you convert that to G-code?
Hardware, mechanical and assembly are my strengths not programing.

Tom
Title: Re: Edge Probing
Post by: Scott on December 16, 2006, 10:28:19 AM
Hey Tom,

I took a look at the file from the edge finding routine that's in the SB software.  My strengths are much like yours, and I'm not the best mathematician by a long shot,  but I can usually kludge through if I have an example to go on.  What would probably take me a month to to (with a lot of head scratching), I know others here could do in a few minutes.   ;)

I don't know how you would make Mach do the circular moves (working it's way around the object), while sensing the probes contact.  Can yo do a G31 with a G2/G3?

Regards,
Title: Re: Edge Probing
Post by: Brian Barker on December 16, 2006, 04:49:10 PM
There are no tools to make probe points into a Gcode profile... You would need to take the points into a Cad system and draw the profile from them.
Title: Re: Edge Probing
Post by: Scott on December 16, 2006, 06:53:45 PM
Hey Brian,

Couldn't those points be translated into g-code just as SB 's Virtual Tool "Copy Machine" can make a .sbp file?  It can also output .dxf point, or .dxf polyline. 

What I don't know is how Mach would pick up those points because you would need to work your way around the object to be probed with a circular motion (the smaller the circular moves, the higher the resolution).  Example below showing what I mean.

Regards,
Title: Re: Edge Probing
Post by: GaryB on December 17, 2006, 02:03:21 AM
Tom and Scott,
Just a thought, but rather than edge probing you could use the "teach & Learn" wizard. Great little tool (thanks Brian) which will give you an edge profile creating you're g-code on completion, more than likely a lot quicker than a probing routine.
Title: Re: Edge Probing
Post by: Brian Barker on December 17, 2006, 10:20:02 PM
Scott it could be done but there is no time to get into a project like that :(  Try the teach wizard and I think you will find that it is a fast way to do what you are looking to do... Just not with a probe...

Thanks
Title: Re: Edge Probing
Post by: Scott on December 18, 2006, 12:09:11 AM
That's ok Brian, I was just checking for Tom.  He's got his probe all set up with no place to go.  :D

Are you saying that you can make Mach sense the probe contact with a G2/G3? and not just with a G31?

Is there a video or some documentation for the "Teach Wizard"?  It looks simple, but I haven't got a clue of what I'm doing with it.  Maybe if I were at the tool instead of my desk I'd figure it out.  :P

Thanks,
Title: Re: Edge Probing
Post by: Brian Barker on December 18, 2006, 09:07:41 AM
Only G31...  and that is where the problem comes in for probing the outside of the part.. you need to calc the vector that the part is headed in and predict where you should hit the part. It is not as simple as you think  but it can be done (It would be way cool to have that on a router! )