Mitutoyo CMM/ Mcosmos help needed

[Bob W.]

My CMM has been installed (Crysta Apex S9106) and I need some guidance on the Mcosmos-2 software.  I have training scheduled for early February but I'm the type that likes to figure out as much as I can on my own before the training.  i end up getting a lot more out of the training that way.

 

I have been able to go into learn mode and establish planes, lines, points, etc... by manually taking points using the CMM with the joystick.  I have also gone into the CAT1000PS module and imported STEP files of my parts but that is about it.  What do I need to be able to take measurements off the CAD file?  I know this is a pretty open question but any guidance would be a huge help.

[Clarence L Cook]

Bob,

 

I have a B&S DCC Gage with the PC-Dmis software, so I can't speak directly to your CMM or software, but, what I found with my software (self taught) is that it was easier to create the lines, points and arcs in Mastercam.  There is a switch between surface/solid selection and wireframe selection.  I found that I had more control over my hits with the wireframe.

 

One piece of advise that I believe holds true across CMM software is to understand how the CMM references the part and the effects of the small deviations, especially in rotation.  An example, I machined a test piece with two angles that I wanted to measure.  One of the angles had a short leg (approximately 3/4") while the other was considerably longer (2").  The difference between the angles was an order of magnitude different (.1 degrees on the short vs .01 degrees on the longer).  Those small deviations in hit values can have a profound effect on the end result.

 

Get to know your CMM and its idiosyncicies (which I expect you will) before you trust the numbers that you are getting.

 

Kind regards,

Clarence

[Clarence L Cook]

Bob,

 

Did you get the scanning head with this CMM?  If you did and you plan on using that feature with aluminum parts, I have read that you should not use the ruby stylii when scanning.  Ruby is made of aluminum oxide and as I understand it, you will loose the shape of the stylii over time because of the natural affinity aluminum has for itself.

 

Kind regards.

Clarence

[mkd]

shop I helped startup in 2007ish got a Crysta with mcosmos and geomeasure.

amazingly confounding software clearly designed by a descendant of Rube Goldberg....

they ditched it in favor of some Dmis solution after i left.

 sorry, just my honest opinion.

[taperlength]

Get used to breaking styli when learning the CMM (and a few after learning)

 

If the CMM reports the part is out of tolerance, check it with conventional measuring tools before throwing it out or changing settings on the CNC machine.

 

Small foreign objects (like scotch-brite grit) or tiny burrs, can cause bad measurements on the CMM.

[Bob W.]

shop I helped startup in 2007ish got a Crysta with mcosmos and geomeasure.

amazingly confounding software clearly designed by a descendant of Rube Goldberg....

they ditched it in favor of some Dmis solution after i left.

 sorry, just my honest opinion.

Yeah, I'm stuck with it for now.  I will give it a fair shake but will not hesitate to move on if I conclude that it is crap.  From what I hear, a lot of the CMM software is crap...

[mkd]

i was just going to edit out some of my colorful language as to not rain on your parade.

I did the training, then tried to tinker with it...then had to focus elsewhere. So i didn't give it a fair shake.

you'll have more success and maybe a different opinion.

 suggest to start looking for a consultant now; customizing those reports can be a bear.

[Bob W.]

i was just going to edit out some of my colorful language as to not rain on your parade.

I did the training, then tried to tinker with it...then had to focus elsewhere. So i didn't give it a fair shake.

you'll have more success and maybe a different opinion.

 suggest to start looking for a consultant now; customizing those reports can be a bear.

No problem.  I always learn best if I tinker before the training but on this I'm not sure where to start.

[mkd]

been a while...

cosmos is just for creating motion and actually pretty slick/inutitive.

the heart of the sys is geopak.

 

the first thing you're going to need to figure out is how to create/store/manage probe calibrations.

each angle you intend to use during insp is going to need a calibration (on sphere supplied).

[THEE THAINZ™]

From what I've seen at work most discrepancies are caused from improperly calibrated tips.

[mkd]

the first part of a program is going to establish your part datums.

the probe routines are limited in their travel so it is important to fixture the part pretty close to the same spot on the machine.

 one of those rego plates (overpriced 1/2" alum plate with metric tapped holes) and assorted clamps would be a good start.

[Newbeeee™]

From what I've seen at work most discrepancies are caused from improperly calibrated tips.

And incorrectly created planes.

[THEE THAINZ™]

And Yes planes.........there's no Tattoo to call it out for the inspectors. 

[Watcher]

Yeah, I'm stuck with it for now.  I will give it a fair shake but will not hesitate to move on if I conclude that it is crap.  From what I hear, a lot of the CMM software is crap...

 

Metrology software requires skilled joqueys. You must master basic geometry, how to properly build primitive elements, such as DATUMS, planes, cylinders, lines, point, intersect stuff, projection and so on...

 

Unfortunately most people behind them don´t have a true understanding how all the geometry talks to each other, and to the software.

 

As mentioned above, the basic alignment is crucial, and rotation is easy to be overlooked. If you have scanning, use it. It will increase the accuracy of your measurements significantly.

 

Calibration is also crucial. Measure the sphere in at least a dozen points. Don´t do like average guys, that pick the min. number of points, 5 I think, and start the measurements. Always invest the right time in the calibration of the stylii.

 

This is also true for machine probes: All inspection hardware has errors, and the thing about them is that it´s a reproducible and known error. Touch force, feed, gravity, stylli material, head angle, temperature, etc... All these are part of your calibration set. If one of them changes (Head angle for example), it´s a new calibration. The key to reliable results is to repeat, during the measurement, the same circunstances you had during calibration. On a machine tool this is equivalent to not hold your feed during measurement, otherwise the stylii deflection won´t be the same. Gravity changes the calibration significantly if the stylii is on a horizontal position for example. This affect results. Same for CMM, arm gages, machine probes, etc.

 

Most metrology software is capable, and Mitutoyo has been around for a long time. Invest the right time in learning it right, and get the right guys to train you. Most problems people have with inspection software is related to the fact they don´t know how to use it effectively, and the thing is that when it comes to measurement, a small miss in your setup can lead to a measurement error that you can´t validate visually. It´s not like fixing something on your CAx system, where you measure theoretical entities.

 

Clarence shared some good points. Keep them in mind all the time.

 

Have a happy journey into CMM world! It´s a very nice game, and will tell you a lot about your machine tools and your processes. You will learn that not everything is what you think it is. What you will learn will make you a better programmer.

[Colin Gilchrist]

Hi Bob,

 

Have you looked into the Verisurf options that are available for CMM Programming? I'm sure Ron can chime in to correct me if I'm wrong, but I thought that Verisurf would allow you to use Mastercam as the programming interface to your CMM. That way you wouldn't have to learn a separate software package just to inspect your parts...

[Newbeeee™]

One thing we do have sat on the bed of our CMM at all times, is a calibrated 1.5" dia ring gauge.

Although we may regularly calibrate the stylus against the sphere, IMO it's always a good double check (and comfort factor) to then measure the ring gauge.

If it's within a couple of microns of what it should be, that's good enough for the boatbuilding we do

[Bob W.]

Hi Bob,

 

Have you looked into the Verisurf options that are available for CMM Programming? I'm sure Ron can chime in to correct me if I'm wrong, but I thought that Verisurf would allow you to use Mastercam as the programming interface to your CMM. That way you wouldn't have to learn a separate software package just to inspect your parts...

I haven't.  I don't know the first thing about CMMs other than they measure things and can be really accurate.  Is the CMM/ software relationship similar to CNC machine/ CAM software relationship where the CMM is just hardware that can be run by a number of different programming software?  I was under the impression that they were more closely integrated with the programming software (Mcosmos, etc...).

 

And people keep mentioning datums...  What the hell is a datum?

 

[Bob W.]

Calibration is also crucial. Measure the sphere in at least a dozen points. Don´t do like average guys, that pick the min. number of points, 5 I think, and start the measurements. Always invest the right time in the calibration of the stylii.

The calibration routines the machine comes with are fantastic and it takes about 80 hits per probe orientation and when complete it provides a report which includes the degree of error that has been comped out.  There is a matrix where you can select the various angles to calibrate at and there are a few hundred in total so one could easily spend 30+ minutes calibrating a probe for every index combination.  Once the orientations are selected everything is automatic.  It takes several hits on the ball and also takes several hits while sweeping/ scanning the sphere.  I have the SP25 scanning probe along with two styli racks in the tool changer.  It was a demo unit and was very well set up.  The max volumetric accuracy error over the travels was 1 micron during the machine setup and calibration.

[mkd]

Hi Bob,

 

Have you looked into the Verisurf options that are available for CMM Programming? I'm sure Ron can chime in to correct me if I'm wrong, but I thought that Verisurf would allow you to use Mastercam as the programming interface to your CMM. That way you wouldn't have to learn a separate software package just to inspect your parts...

verisurf is great for a faro arm.

IIRC a saw Tim M. (in my friends list) using Verisurf to run a real CMM but that was a long time ago.

 he would be a better resource for info that me.

[crazy^millman]

Verisurf has been working hard on the CMM Programming side of things for some time. That exact machine would have to be handled by your local Mastercam dealer and they can get the right person to come in and evaluate what it will take. Steve Linsk is a Verisurf Rep in your area and works closely with MCAMNW.

[Watcher]

I´m sure Bob will invest the right time in learning Cosmos / Geopak Win.

 

It´s way too early to talk about a replacement for a turnkey solution that was created by the makers of the CMM.

 

JM2C

[taperlength]

Does it come with the PH10M/10MQ motorized probe head?

[THEE THAINZ™]

   Bob,

Start looking into fixturing and part holding. TECO (just one brand) makes CMM clamp kits. They look like a Stephens plate (http://www.stevenseng.com/). Once you get up and running you can start building programs to inspect parts in much the same way you have the probes in you machine run. At the last place I worked we would have target points that you would manually center on then run a sub program that would find all the datum features on the inspection fixtures. Thru this process it would align and level to this location, then you would load the inspection program hit run and it would run an inspection program and print the results. Once you have this dialed in any one can set up and inspect with minimum training.

[Bob W.]

Does it come with the PH10M/10MQ motorized probe head?

Yes, PH10MQ.

[Clarence L Cook]

Colin G. - EDAC Technologies, on 28 Dec 2015 - 05:25 AM, said:

Hi Bob,

 

Have you looked into the Verisurf options that are available for CMM Programming? I'm sure Ron can chime in to correct me if I'm wrong, but I thought that Verisurf would allow you to use Mastercam as the programming interface to your CMM. That way you wouldn't have to learn a separate software package just to inspect your parts...

I haven't.  I don't know the first thing about CMMs other than they measure things and can be really accurate.  Is the CMM/ software relationship similar to CNC machine/ CAM software relationship where the CMM is just hardware that can be run by a number of different programming software?  I was under the impression that they were more closely integrated with the programming software (Mcosmos, etc...).

 

And people keep mentioning datums...  What the hell is a datum?

 

 

Datums are the features you measure to orient the part in CMM space.  At a minimum you will need to measure a plane, a line and a point.  I typically use the place to establish my Z.  If you have a piece of grit under one corner of the part and you measure a plane off the top of the part, the software will adjust the part so that it is mathmatically flat even though it is not really flat.  A line is use to adjust for a rotational error, ie, the part is not perfectly parallel to a given axis (x or y).  The line can also be use to set a part original value if applicable.  

 

There are a lot of ways to establish your datums.  They are critical to getting good measurements from the CMM.

 

Kind regards.

Clarence