Never Had One--Is a Renishaw Probe on VMC Worth the Cost?

I'm trying to make some end of the year decisions on purchases. One option that keeps getting suggested is a probe for our 2015 Doosan VMC. We have one with a probe in another location. I have never used a probe. We have a Haimer Taster on this one and I love it. It's so much better than an edge finder. We all know a Renishaw probe is expensive, it will be north of 10K. We do several setups per week. Are these probes worth the cost, are they that much better than a Haimer?

You will get lots of differing opinions on this subject. Most people will say yes. Probe rules.
Then you will have the occasional guy like me, that says no. Haimer is all you need.
In my opinion, unless you are planning to use it for in process inspection.
Or, you have parts that need touched off on every part. where you push cycle start, and the first thing the program does is call up the probe, and reset the origin.
The Haimer is just as quick.
The only exception is probing a bore, or boss. Probe beats Haimer there every time.
The real value in my opinion, with a probing system, is the tool setter.
They make setting offsets a breeze. And, broken tool detection is really nice as well. Esp. if you do a lot of unattended work.
Every shop is different. It really depends on your work.

The good about probes:
1. they are only as good as their calibration/machine accuracy
2. with proper macros/ routines ( read simple, powerful, easy to use and fast) they make setups go much faster even one offs. You'll find your self probing instead of using end stops.
3. They are great for finding center of flamecuts, castings, etc.
4. they generally are not bad to program around.

The bad:
1. they are only as good as calibration/ machine accuracy. You can't fix a farted up machine with a probe, and a probe thats not calibrated costs you more than you save. Its like tramming bridgeport heads, should be done periodically even if not crashed
2. keep extra stylus on hand - you'll break them- especially when batteries die in mid cycle
3. you'll never have the one cycle you need at the moment- you have to re skin the cat sometimes.
4. if you absolutely want to know, you can't beat a coax, gage blocks, and mechanical touchoff, but it will take longer to do.

I have had probes... the one particular machine I have not repaired it since the last time it went down. That machine is long in the tooth and I'd rather save the money for the next machine ( I have one in mind, but I don't know if I can afford that much awesome).

Although I can get by with the old methods, a probe is so much quicker once you get used to it. Probes aren't all that for inspection....you are still only as good as the machine. They are GREAT at shortening set-up time and helping you with problem parts. (Castings, angled parts, datums from a hole, etc) Once you figure out how to macro program for one, you can do all kinds of things to help you on the machine. I personally would not buy a machine for general work without one.

I have used probes for a long time, anything else seems wasteful.
Once you to learn program them...X,Y,Z zero corner on a part. Press start button, walk away.
Verify angles on your 3 cnc +2 manual press button.
Varying part stock when the datums are not you fixed vise jaws, press button.

As noted by Tony do not use them as a CMM and never inspect on the machine a part is run on.
Size comp is ok and a very good use, inspection...never.
Bob

I agree very well with Tony and CarbideBob and I've only been programming one machine with a probe.

Even for clocking round parts a probe is exceptional. No need for locating softjaws if you have a feature that pokes through. We have several parts that were located and bolted to a fixture using three through-holes. Alignment wasn't exceptionally important, but at least a general requirement (probably got on average ±2°). Well no more fixture, now we toss it in nominal-size softjaws, probe center, cut first side, flip and align "by eye" one through-hole along the Y-axis, probe center hole, probe through-hole, set #500 to store angle offset, run G68X0Y0R#500 and away it goes on the second side. Aligning by eye gets it within a degree most times, I think max has been about 1.2° but now the program compensates and they run better than ever and much more securely than on the fixture, on which tooling had to be watched carefully to avoid bolt heads and they marred the top surface on top of that.

We use it to check critical features by comparison (floor depth from another feature for example) for in-process work and set tool offsets IF within a certain range, or alarm if outside that range to alert an operator or set wear offsets for tools in a few instances.

One of the most fun projects is a part that gets 80% of the material removed, sawn in half, then finished with the halves pointing up in the vise where it was flat previously. The work coordinate in Z is now set by probing the bottom of the inside feature milled when the part was one piece as the overall size isn't important but the feature-to-height is. It's been completely trouble-free since moving that to the probe.

We hold tolerances in production that were damn near impossible for me before we didnt have the probe. Parts we used to sweep manually with a .0001 indicator every time we can have general operators load and just use the machine to probe. I'd say 1/3 of the production parts I'm making right now are .001-.002 True Position from Op1 to Op2 loads.

I have 2 machines with Renishaw probing, and one without. We use a Haimer on the machine without probing. I don't mind either way, but I doubt I will ever buy a new machine again without it. It eliminates a certain amount of human error. Run calibration on work probe and tool setter every 90 days max.

I learned on a mill with spindle / tool probing. Now I watch other shops during setups or dealing with a difficult part that likes to move around, and I just wonder how many tens of times my probes have paid for themselves... Like others have said and many more will say, I will never, ever buy a machine without probing.

munruh said:

We do several setups per week. Are these probes worth the cost, are they that much better than a Haimer?

Click to expand...

What sort of setups, and is it only the setups or are you needing to currently dial every part in to confirm location?

If you're having machine issues(lack of accuracy) or material issues(stress release) where you have to confirm position before proceeding to a feature or finishing cuts, then yeah it's probably worth it.
If you're only dialing in a handful of small quick parts for location between operations, then maybe it's not that worth it, but if it requires training McOperators to run it on the night shift, maybe the probe is the better option. If they're one time parts, finished on the same shift they're setup, then skill level isn't as much of an issue.
If you got a lot of positions to pick up in a large weldment, or generally complex or large part, the probe makes sense. Especially with the number of stylus options to facilitate picking up those locations.

I just wonder how many man-hours it saves the shops running them in just eliminating the set-up of a work stop for multiple parts... Sure, it's just a couple minutes to set one up, but over many parts that time adds up. Add in what Adamkinder mentioned about not having to make special fixtures, which is a losing proposition on 1 off parts and the ROI is probably measured in weeks, not years.

Tonytn36 said:

I just wonder how many man-hours it saves the shops running them in just eliminating the set-up of a work stop for multiple parts... Sure, it's just a couple minutes to set one up, but over many parts that time adds up. Add in what Adamkinder mentioned about not having to make special fixtures, which is a losing proposition on 1 off parts and the ROI is probably measured in weeks, not years.

Click to expand...

That is really a nice feature of a probe. We ran a part one time where the probe was used to identify if the part was loaded correctly for the milling op. Thinking back, that part was 11" diameter, with one feature that we probed from. I am not sure how I would have made a fixture for it, not to mention the time and material it would have taken to make, then you have to prove out the fixture, etc. Instead, ran a probe cycle that set a bogus (not used) work offset. If part was loaded incorrectly, the probe would alarm out and machine stops. Probably took me all of ten minutes to decide how to do it, add code to program, and verify it worked.

WILLEO6709 said:

The good about probes:
1. they are only as good as their calibration/machine accuracy
2. with proper macros/ routines ( read simple, powerful, easy to use and fast) they make setups go much faster even one offs. You'll find your self probing instead of using end stops.
3. They are great for finding center of flamecuts, castings, etc.
4. they generally are not bad to program around.

The bad:
1. they are only as good as calibration/ machine accuracy. You can't fix a farted up machine with a probe, and a probe thats not calibrated costs you more than you save. Its like tramming bridgeport heads, should be done periodically even if not crashed
2. keep extra stylus on hand - you'll break them- especially when batteries die in mid cycle
3. you'll never have the one cycle you need at the moment- you have to re skin the cat sometimes.
4. if you absolutely want to know, you can't beat a coax, gage blocks, and mechanical touchoff, but it will take longer to do.

I have had probes... the one particular machine I have not repaired it since the last time it went down. That machine is long in the tooth and I'd rather save the money for the next machine ( I have one in mind, but I don't know if I can afford that much awesome).

Click to expand...

Everyone has different experiences, but I have never broken a stylus. I can't imagine the battery dying mid cycle, but maybe. They have a warning led when the battery is dying now too, at least our Renishaw does. Now I have broken the tool setting arm that connects the disk to the body on the OTS, but I am blaming Haas for a shitty design on the EC400...

Yes Yes Yes..... well it depends on the work you have. Everything I do is a one off so it helps a ton. We only have one and its on our VF3, the option was about 5 grand. We are still quoting a Okuma Genos and the same thing is about 15 grand, and I still would not hesitate for a second to get it.

Its a tough pill to swallow if you're purchasing after the fact but if you have any leverage in the negotiation of a new machine dealers will work with you.

We got our first probe as a part of a machine purchase a few years ago and again on the latest machine purchase this past year. At this point I don't think we will get a machine without it. I have to do a 6 position setup this morning and expect it to take me about minutes.

The touch setter is equally impressive. If your planning on running unattended, the broken too detection is damn near the coolest thing there is.

We have gotten spindle and table probes on the last 5 mills and don't plan on getting machines without them. Running tool break detect in cycle and verifying part location are helpful even during short runs.

Part of your Doosan's EOP package contains the Renishaw probing and tool setting routines, already built in. These are strictly for common probing and tool setting functions. The Renishaw software will be needed to perform the more advanced functions. Personally, I would never buy a machine without a probe and tool setter. As others have said, the time saved can be enormous. Learn to use it and learn to use all of it. You will be surprised at how much you can do. We don't sell many VMC's anymore without probes and tool setters.

If you have any questions about your machines usefulness with a probe and tool setter, call me. I will try and answer all your questions.

Paul Anderson
Doosan Machine Tools America
[email protected]
973-618-2457

dstryr said:

We hold tolerances in production that were damn near impossible for me before we didnt have the probe. Parts we used to sweep manually with a .0001 indicator every time we can have general operators load and just use the machine to probe. I'd say 1/3 of the production parts I'm making right now are .001-.002 True Position from Op1 to Op2 loads.

Click to expand...

This is the kind of stuff probes are good at.

I would recommend a spindle probe and toolsetter, yes.

We have three mills we use for job shop work, a VF1, VF4SS, and VF3. The VF3 is the only one with a probe and toolsetter. The difference is amazing. On the other two, pickups are done with edge finders and indicators. Tools are offset using one of those light-up tool touch-off probes.

You can touch off an entire carousel of tools in a couple of minutes... worry-free. Compared to cranking each tool down, each time risking cranking too much and crashing that $100 thing.

And the probe as well. It tends to vary a few tenths on pickups, but very very seldom does that cause an issue for us. The speed is so much better, compared to using an edge finder and calculating.

If I bought a machine that I really wanted to make money off of, I'd get a probe and toolsetter!

I've never caught myself saying "I wish I would have not ordered the tooling probes".