Calibrating a Part Probe?

We have several mazaks at our shop but I've not been running them to long. Our latest is a 510 with pallet changer and fusion control. I broke the probe the other day and have a question about the recalibration. I used our tool setter to get the runout out of the new probe and bolted a ring gage to the table. Then I just eyeballed the center with my 6 inch rule and taught zero and wrote a program to run the calibration. Now to my question. My friend said that I need to indicate the ring and then teach zero directy in the center and then run the program, but I figured if the machine is going to probe it that would be a wasted step. Maybe I'm missing something. I'm not against indicating the ring if that is necessary but if it is not necessary I don't want to be wasting time doing it.

Are you using the Renishaw macros, or the Mazatrol inspection routines?

As Joe mentioned, are you calibrating using Renishaw macros, Mazatrol .... or going to use both?

To answer the ring gage question.... Indicating the ring gage is a necessary step if you want the probe to be as accurate as it can be. Not to mention the fact that you don't know how accurate the runout was on the previous probe tip when it was calibrated. The calibration process is what will take out any runout from the stylus, probe shank, head tram (probe), indicator deviation (ie: indicating on a HMC), stylus diameter and whip (from long shanks).

If you 'eyeballed' the ring gage, then ran the calibration cycle to that, you've just calibrated the probe to your eyeballed location. When you start running your probe in programs, you're going to find errors in positioning because the your probe deviation parameters will be carrying the calibration error from your eyeballing. Basically, the more accurate the known ring position is during calibration, the better the probe accuracy. I'll usualy set up a new probe tip using a pre-setter but I always double check and make the final adjustments by indicating the probe in on the machine. Then, indicate the ring gage to calibrate. After that (usually on multi axis machines: HMC, 5-axis, Integrex and such), I'll program a bore and maybe some other related features to check the accuracy of the probe relative to the machine coordinate system. The last step is generally not necessary, but I have had it find a problem and required to redo the calibration.

Thanks for the replies. I am using the calibration under "MMS" in the mazatrol program. I'm not sure if that's considered Mazatrol or if the Renishaw macros are hid within that option. Maybe you can tell me more about which is which. Thanks again.

japcas,

If you're using the Mazatrol measuring routines, your probe will only be as accurate as the job you do dialing in the run-out of the probe. On the plus side, your calibration routines are only calibrating the stylus diameter, and not the XY mis-position of the stylus to the spindle centerline. So after you calibrate your stylus diameter on your ring gage, run a probe cycle to find the center of your ring gage, and then run your diameter calibration routine again, just to wipe out any tangency errors you picked up the first time from your "eye-ball" calibration.

That's why it's better to use the Renishaw macros in EIA mode, because the XY error of your probe is stored into a 500 series variable, and added in every time you use a Renishaw probing cycle. You only have to get the sytlus somewhat close, and the software does the rest.

Since you're using the Mazatrol routines, just make sure you get the runout of the probe stylus dialed in PERFECT.

As Joe mentioned, those are Mazatrol routines. But the same rules apply, dial in the stylus, indicate the gage ring for position, calibrate probe.

And actually... Mazatrol does store the XY error for the probe. Not sure where the comment is coming from but Mazatrol stores this as well under the machine parameters at L1 and L2. The function is the same as the EIA error adjustment. Just for note, L3 and L4 is what calculates for probe tip radius/diameter.

In either case, I prefer to dial in the stylus as close to "perfect" as possible, then calibrate. The idea is to have as little deviation stack up as possible for good, solid probing.

Guys thanks again. You make it easy to understand. I'll be sure to make a few notes about this when I get back to work so I'll do it right next time.

One other question about using the probe. Should it be able to probe a hole on a 45 degree angle as accurately as it does when moving in line with the x and y axis? When I say accurate, I mean within .001 to .002. Not tenths.

Yes, it should fall well within .001 or .002 of accuracy. This falls back to how well you indicate in the probe tip and the ring gage at calibration.... which by the way, accuracy of gage diameter is important as well. Since the Mazatrol calibration cycle doesn't calibrate with theta (at an angle, at least not that I can remember), the above mentioned items will be critical. Renishaw macros can be tweaked to calibrate for many things and scenarios. But, for the most part, since probe tips are extremely round, the indicating process of probe calibration should take care of any deviation down to the smallest of levels.

Thanks Phsycomill. I plan on doing some tests with the ring gage when I get back and check the probe runout. I appreciate the help.

If i may,

We have a PFH4800 with a probe that has never been used before (2001 fusion). We dont have renishaw macros. When i call up the probe i get an illegal mms unit or something alarm. Is there something i need to do to get this working? i have replaced the battery. I think its a MP10 probe. What is the best way to get started if starting from square one?

sakis, is your probe defined in the tool data
with the name (tol sens).when you press touch sensor it will call it like this. you have input a tool diameter and you also have a tool lenght
entered. if you are missing a data you will get an alarm.
to clear the alarm hold reset button and press cycle start.

As mazakboy mentioned.... my first thought. You have to have the probe defined on the Tool Data. Or.. since your machine is recognizing the need to trigger a probe, you must already have it defined but the machine just isn't seeing it and therefore the alarm. An MP10 is an optical probe so you may be having a "line of sight" issue. So, try tool changing the probe into the spindle, then unclamp the probe into your hand and hold in front of the OMM (you should have a transceiver inside the machine). Unlike the MP700, the MP10 only has a couple IR outputs at certain indexes so make sure one of these is facing the OMM. Then hit reset to see if the alarm clears. If not, you may have an issue with the OMM or possibly with the MI12 interface which is in the electrical cabinet. Depending on how the factory installed the probing equipment, it may also have a reset switch on it as well.

Check the probe in your hand first in front of the OMM though and see if the alarm goes away...

Sakis, also make sure you have a fresh battery in the probe! My MP700 battery dies about 3-4 times a year.

When the battery is dead, I get an illegal MMS Unit alarm.

At one point, I also had to remove the clear cover of the OMM unit, and polish it with some plastic polish. The constant blasting with 8000sfm aluminum chips had turned it solid gray, and the IR couldn't penetrate it. Again, Illegal MMS Unit alarm.

P.S.- You wanna sell that PFH4800?

Joe788 said:

Sakis, also make sure you have a fresh battery in the probe! My MP700 battery dies about 3-4 times a year.

When the battery is dead, I get an illegal MMS Unit alarm.

At one point, I also had to remove the clear cover of the OMM unit, and polish it with some plastic polish. The constant blasting with 8000sfm aluminum chips had turned it solid gray, and the IR couldn't penetrate it. Again, Illegal MMS Unit alarm.

P.S.- You wanna sell that PFH4800?

Click to expand...

Make sure you've turned it on as well. M81/M82 M281/M282 ETC.
During our renishaw calibration cycles the probe turns off and on several times. As soon as it goes off, a soft alarm is posted, which disappears once turned on again.

Roxxanne said:

Make sure you've turned it on as well. M81/M82 M281/M282 ETC.
During our renishaw calibration cycles the probe turns off and on several times. As soon as it goes off, a soft alarm is posted, which disappears once turned on again.

Click to expand...

once probe in and ready for measurement, Mazak PLC does not turn it ON and OFF several times as it is not in ladder diagram. . Once probe is activated it is stay ON until given a command TOOL CHANGE ->NEXT TOOL and special tool goes back into a magazine. At that moment PLC pulses a short signal to turn it OFF. IT is all well written in ladder diagram.

japcas said:

We have several mazaks at our shop but I've not been running them to long. Our latest is a 510 with pallet changer and fusion control. I broke the probe the other day and have a question about the recalibration. I used our tool setter to get the runout out of the new probe and bolted a ring gage to the table. Then I just eyeballed the center with my 6 inch rule and taught zero and wrote a program to run the calibration. Now to my question. My friend said that I need to indicate the ring and then teach zero directy in the center and then run the program, but I figured if the machine is going to probe it that would be a wasted step. Maybe I'm missing something. I'm not against indicating the ring if that is necessary but if it is not necessary I don't want to be wasting time doing it.

Click to expand...

There are programs to find the center of a circle given three points on the perimeter. Google is your friend: or a really good pal that can program for you. As a linux user I used C. In addition I made a probe for my mazak V5 that was repeatable to about 0.0001-0.0002. :-) but that is a different subject.
Do your first set of points parallel to the axes. Try another set at 45 degrees which after calculating your center should tell you how good ... or bad you are. Set part zero (center) to the calculated numbers and you should be good to go.
YMMV but it might be worth a try.

Cheers!

indicate centered on ring gage using setup same length as probe
.
run probe calibration then have it probe center position of ring and then use indicator to confirm probe calibration is good enough.
.
spindles tend to lean or be out of tram alignment. if you then use a much longer or shorter indicating setup its common to see you are not centered on the ring. could be easily .0005" offcenter with different length indicator setup. does same thing with different length mills and boring bars
.
and of course as machine warms up and cools off things change .001" easily