Digitizing Probe

[domino11]

HI,
Has anyone out there done any work with a digitizing probe on the mechmate or other CNC? I am looking for peoples experiences and outcomes.

[Gerald D]

The term "digitizing probe" is a glorification of what the devices actually do - they are just contact switches. You can achieve the same result by covering the workpiece with tin foil and putting a knitting needle on the z-slide and then checking when the needle makes electrical contact with the foil.

[duluthboats]

Hi Heath,
There are many ways of collecting points from an object, from high end laser stuff to a good square and rulers. I think Gerald’s idea is a good one. I have done 2D profiles on a mill with an edge finder and the DRO. I have also used a transducer with digitizing software and a 3 axis CNC mill for 3D work. The CNC method is better only in that it records the points for you instead of you writing them down. You still have be able to use the points some how. For 3D work you need good software that can change the points into a useable surface. You may have to do some editing before you can use that surface for machining. You will want to collect the fewest points you need to describe a surface. The more points you have the more problems you have getting a smooth surface.
If you have any specific questions I would be happy to try an answer them.

Gary

[Gerald D]

We actually did some knitting needle & foil probes to figure out if a real probe would help the business. Quickly discovered that the probing is the dumb part and that the result of the probing needs a lot of processing to make it useful. Google "point cloud (http://www.google.co.za/search?hl=en&q=%22point+cloud%22&meta=)"

Also, if the probing is set up wrong, you ram the probe into the job - much cheaper with a knitting needle.

[duluthboats]

That is very much my experience. I been in 3 shops that had good probes and software, they are used a few times and then sit in the box. It is extremely time consuming.
Gary

[revved_up]

A probe would actually be a benefit to me to recreate desigsn in order to repair some of the old furniture around here and I know of some people that made some money off of them, my question: if I should decide that I want to try to set one up does it require anything extra hardware in the control box or just uses existing inputs in the pmdx, cadcamcadcam.com has one and it says it will work with mach3 any input will help as I am getting ready to start buying some of the electronics and want to order right the first time.

[Gerald D]

As said before, a knitting needle & foil works as a probe connected directly to a single vacant input on the BOB, without further hardware. A "probe" is a very dumb device.

[garyc]

Here is another way of doing point clouds
http://www.machsupport.com/forum/index.php/board,67.0.html

[normand blais]

DIY 3d probe .
http://www.vinland.com/Touch-Probe.html

[sailfl]

Normand

Are you going to make one?

[normand blais]

Oh hi that was fast I was just reading about the software accutran on the same link ,interesting .To use after you get the pointcloud . I alerady got one that I bought with my sb. I just post the link cause I tough it was interesting and does not look to hard to make and look pretty accurate looking at the result .
Normand

[PEU]

DIY 3d probe .
http://www.vinland.com/Touch-Probe.html

Im making myself one based on the photos shown on this page, so far I made the ball contacts and the contact holder, only need to make the mount, hopefully tomorrow.

Will post photos when finished.