Probes

I am going to need a probe for my new machine and wondering what people are using. Khai recommended Wildhorse Innovations probe and at $109 seems pretty cheap. Really only going to use it to set up a couple of pieces so I don't need anything too fancy. Hoping to be able to plug it into the probe port on the PDB and I guess I am going to need to know how to wire that as well...

Thanks guys!
-Keith

Keith,

I've used several different kinds of probes over the years, including the WildHorse. The one I've used 99.9% of the time for the last 3-4 years is the cheapest, simplest of the bunch. I have a 1/4" TTS set-screw holder with a short piece of 1/4" rod in it. The length is set to exactly 3" from the TTS flange. I then have a 3/4" x 1-1/2" piece of PCB material (from RadioShack) with a wire soldered to it. Hold the PCB material against the surface I need to probe, with the copper side of the PCB material facing the probe, and do the probe. This allows me to do X, Y, and Z. If the probe get accidentally run into the workpiece and bent, I just toss it and cut a new piece of 1/4" rod. The wire from the PCB material can be connected to any BOB input, along with a stiff pullup resistor (anything from 100-500 ohms is good) to +5V.

Regards,
Ray L.

BTW - If you're going to be probing, do yourself a favor, and buy a copy of MachStdScreen (Calypso Ventures, Inc.). It is the ONLY set of truly robust, well-written probing macros I've ever seen for Mach3. Use any of the many macros that are floating around the Internet, and you're pretty guaranteed to have problems with unreliable behavior, and end up with a lot of broken probes.

Regards,
Ray L.

I've only used the Tormach Passive Probe personally, so my experience with probes is based on that model alone.

The probe mechanism in the Passive Probe is extremely simple and this one looks about the same. My *guess* is that both would perform about the same in terms of reliability and accuracy. I, personally, wouldn't worry too much about the Wildhorse Econo-Probe suffering from being too "cheap". I'd like to reiterate that I haven't even seen one in person though.

A possible weak point of the Wildhorse probe is that the actual probe tip is rigid. If the probe crashes it's likely to destroy the tip but it might damage the body of the probe too. The Tormach probes (and others, I'm sure) use a breakable tip that protects the probe body. Of course, Tormach's extra tips are almost as much money as a complete Econo-Probe. There are other breakable probe tip options, but I haven't tried any myself nor can I remember the brand of the setup I saw recommended elsewhere on CNC Zone.
[PS]
Oh, the very second post on that thread I link to below was where I saw the alternate probe tips. Here's the recommended web site: itpstyli
[/PS]

Are you using TTS tool holders? If so, I'd recommend getting a low profile holder like this for the probe. It'll give you about 1 extra inch of Z travel.

Last thing: here's a thread about edge finders: Probes: Active vs Passive vs good old fashioned dial indicators and edge finders
It might have some useful info. If you read through the thread you'll see that I blather on about the Haimer Taster, which I think is awesome. Depending on what you're doing it might be better or it might be significantly worse.

The WildHorse has considerable over-travel. And, if you go beyond that, all that breaks is an easily-replaceable plastic piece.

Regards,
Ray L.