How does touch probe connect/work interface to a CNC machine?

Gentlemens....

I am working with a customer who has a bunch of Robodrills with Fanuc 31i controls as well as some Mori's and Hyundais also with Fanuc controls (not sure the specific model control on those).

I am trying to make things flow faster through the shop, and right now a LOT of time is spend inspecting parts, especially because a lot of the parts have complex surfaces or features/locations which are difficult to measure.

Upgrading to probing from the likes of Blum/Renishaw on these machines would be nice, but it's simply not in the cards right now, but could be in the future if the value of probing was demonstrated and made clear.

I'm an electrical engineer and on my own CNC machine, I "hacked" it to add probing. I bought a probe which is essentially a 5-axis switch that switches on contact with the part. My machine has a Mitsubishi control and I was able to cobble together a system where the probe contacts the part, a signal is sent to the NC control which causes motion to stop and the current X/Y/Z position is output over serial which I captured. I was using this to build point cloud data for scanning parts.


However, I am thinking I could put something similar together for this customer, possibly. A probing system like a Renishaw OMP60 has the spindle probe plus a control unit. The control unit interfaces with the NC control... I assume it must just have a couple of communication lines back/forth to the NC control and tells the NC unit when contact was made, and most of the rest is handled through the macros installed on the machine? Am I correct?

Basically, if anyone can provide any detail on how probing in implemented on a Fanuc control, it would be much appreciated. Or if there's a manual online I can read somewhere, that would be great.

So you plan on integrating a diy probe and writing all the macros for it?
Basically, the probe ties into the highspeed skip function of the control. Don't know exactly the magic that happens but that's where it happens.
I would suggest getting Renishawe to come into the shop and demo their products and then let them install. If you expect any accuracy out of the system and expect to maintain a budget, this is your only option...not diy.

http://www.practicalmachinist.com/vb/cnc-machining/probing-using-g31-fanuc-121651/

Fanuc CNC Custom Macros: Programming Resources for Fanuc Custom Macro B Users - Peter Smid - Google Books

goooose said:

If you expect any accuracy out of the system and expect to maintain a budget, this is your only option...not diy.

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Well, that's not true at all.

I have a probe system I put together for my existing machine that is as accurate as the probe I bought and I wrote the programs myself - took a few days to get them working as I wanted, but it was a fun challenge that I enjoyed.

There is no need to replicate all the macros that Renishaw provides because I am not trying to make a probing system that will work on any machine and probe any type of part. I'm trying to put together a probing system that will work for a very specific application for a specific set of parts where we have total control over what needs to be probed.

Suggesting Renishaw come in doesn't help when I stated that there is no budget to buy Renishaw probing systems.

3t3d said:

http://www.practicalmachinist.com/vb/cnc-machining/probing-using-g31-fanuc-121651/

Fanuc CNC Custom Macros: Programming Resources for Fanuc Custom Macro B Users - Peter Smid - Google Books

Click to expand...

Good starting point - thanks!

SRT Mike said:

Well, that's not true at all.

I have a probe system I put together for my existing machine that is as accurate as the probe I bought and I wrote the programs myself - took a few days to get them working as I wanted, but it was a fun challenge that I enjoyed.

There is no need to replicate all the macros that Renishaw provides because I am not trying to make a probing system that will work on any machine and probe any type of part. I'm trying to put together a probing system that will work for a very specific application for a specific set of parts where we have total control over what needs to be probed.

Suggesting Renishaw come in doesn't help when I stated that there is no budget to buy Renishaw probing systems.

Click to expand...

No budget? Where's the hardware coming from? You're going to develop surface vector probing routines and collect/process the results...all for free? You're a really nice guy.

SRT Mike said:

Upgrading to probing from the likes of Blum/Renishaw on these machines would be nice, but it's simply not in the cards right now, but could be in the future if the value of probing was demonstrated and made clear.

Click to expand...

Let's be brutally honest here-

If the shop you're working with is so thick in the mud that they haven't already seen the value of on-machine probing for their application in 2018, than you need to cut bait and walk away from this.

goooose said:

No budget? Where's the hardware coming from? You're going to develop surface vector probing routines and collect/process the results...all for free? You're a really nice guy.

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I think you need to re-read my post and try to understand what I am doing here because you ain't getting it.

I said there is no budget to put Renishaw systems on 15 VMC's. Just not gonna happen. I spent under $500 in parts and about 3-4 days worth of my time putting together my probing setup on my machine. It works great and is accurate to a few tenths. Putting the same system on one of the machines in this shop and adapting it for their use won't take very long - and the basic functionality I have in mind would *tremendously* speed up their workflow.

gkoenig said:

Let's be brutally honest here-

If the shop you're working with is so thick in the mud that they haven't already seen the value of on-machine probing for their application in 2018, than you need to cut bait and walk away from this.

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That doesn't really make sense either... if that were true, then any shop that isn't using every bit of tech available to them that would improve their efficiency has no place... what, being in business? No place having anyone try to help them? No place being brought into the 21st century? Naw, that's bullshit and you know it.

There's no way anyone who isn't in the situation could possibly know enough detail about the shop, the machines, the circumstances and the constraints at play to make such a blanket statement like the above.

SRT Mike said:

That doesn't really make sense either... if that were true, then any shop that isn't using every bit of tech available to them that would improve their efficiency has no place... what, being in business? No place having anyone try to help them? No place being brought into the 21st century? Naw, that's bullshit and you know it.

There's no way anyone who isn't in the situation could possibly know enough detail about the shop, the machines, the circumstances and the constraints at play to make such a blanket statement like the above.

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Riddle me this than... how do you get to running a relatively large shop (15+ mills, not a small outfit!), doing finicky precision work and 3D surfaces... and NOT have a clue about probing?

This shit isn't new, most every mill delivered new in the last 5 years has probing on it. The really progressive shops have considered it a standard feature for 10+ years. How can they not figure this out without paying someone cash money to build a fucking probe from scratch to show them? Do you get how insane that sounds?

lol... Do you know how many successful shops there are that have 30 machines and there is not 1 probe in any machine?
Or how many shops that run horizontals by programming 15 work offsets instead of using Center of rotation?

One of the things I've learned from doing some outside consulting is you don't go into a shop that is successful and start telling them they are doing everything wrong! lol

Sounds like the OP needs a CMM more than he needs on machine probing?

To the OP's original question - you need Fanuc manuals. I looked into the question of adding probing to a Fanuc 0MC on my Kitamura. Once you wade through the morass of Fanuc manuals, it is really a logic level (not necessarily standard voltage) connection to the high speed skip input. Sadly, Fanuc manuals are so poorly organized that I needed several to find the required information - which in the end was almost trivial.

dstryr said:

lol... Do you know how many successful shops there are that have 30 machines and there is not 1 probe in any machine?
Or how many shops that run horizontals by programming 15 work offsets instead of using Center of rotation?

One of the things I've learned from doing some outside consulting is you don't go into a shop that is successful and start telling them they are doing everything wrong! lol

Sounds like the OP needs a CMM more than he needs on machine probing?

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Sure! I'm not saying you can't make money in a shop without probing. Lots of places do it.

What I am saying is that it's *insane* to think that you're time/effort is well spent trying to convince management that probing will provide a great ROI by building a probing system from scratch.

Better strategies?

- Call the local Rennishaw rep. A shop with 15 mills doing big money work? I am sure they will be happy to install a spindle probe in one mill as a demo. Their margins are insane; partly because they have the job of convincing shops of the ROI of their product.

- Buy a used Rennishaw system off eBay and instal it/write your own macros.

- Call up Metrol who will sell you their new spindle probe in a complete kit for $3500.