Using a two wire touch probe with shopbot

[jseiler]

Can one use a two wire touch probe with a shopbot? Looking at the connection diagram in the shopbot documentation, it looks like the 5V connection is really only providing power for the led's, while a 2 wire probe is really only providing open/close (normally closed) just like the z-plate. Would the proper way to connect this thing be to connect the red wire of the probe to the plate and the black wire of the probe to the shopbot ground just like the z-zero plate?

John

[paco]

You sure can since I do. One to the ground the other to a free input (by default, #1 is use). Forget about the third/power wire.

[ljdm]

Any issues/problems using the 2 wire probe? I have a probe from another machine, any software glitches, etc, using a 2 wire probe, not a Shopbot probe?

[paco]

Most (if not all) touch probe work the same way: ON/OFF. Just like the Z plate and limit switches. It can't be more simple than that, really.

[ljdm]

Thanks, will give it a shot.

[jseiler]

Awesome. Thank you.

[jseiler]

Lou, I beleive the shopbot probe (like most renishaw type probes) are normally closed. If your other probe is normally closed you should be ok.

John

[paco]

Right, you might have to edit the input setting for the input state (VN) depending on your probe circuit configuration.

[jseiler]

So far, so good. I did a quick scan of a carved star I had (3"x3") using a .1" grid. It worked pretty well. I used accutrans to convert the .sbp file into .obj and 3ds files (accutrans is a very nice program for the price). I'm scanning the star again at .03 stepover.

Overall, this probe works pretty well for the price ($100), but I think the return spring is far too heavy for the application. It left fine grooves in the wood. I'll know more after the hires scan.

How do tolerance and surface parameters affect the scan quality?

John