Multiple Probe Files in One Program

[plopperzz]

I am trying to measure a part that has two features i must measure with an L-probe (in the Z+ direction). The problem I am running into is that unless I calibrate everything in one probe file on one calibration sphere i get out of spec results on the z+ tip.

I have two probe files that I use: one which i do the alignment and most of the measuring, and the other which only does the measurements in the Z+ direction. I calibrate each file using their proper calibration sphere, yet I keep getting the same issue. Tech support was not able to really help at all.

Has anyone run into this before, or know what is going on?

[Don Ruggieri]

You need to calibrate BOTH probe tips on the SAME qualification sphere.

For the first one you can indicate that the sphere has moved. For the 2nd one you MUST indicate that the sphere has NOT moved.

[plopperzz]

You need to calibrate BOTH probe tips on the SAME qualification sphere.

For the first one you can indicate that the sphere has moved. For the 2nd one you MUST indicate that the sphere has NOT moved.

Thats unfortunate. I cannot calibrate each tip that I need on one sphere. I was told using separate probe files would do the trick but it definitely doesn't. Do I have no other choice than to write separate programs then?

[Douglas]

do you have 2 spheres or are you moving it for the second calibration?

[plopperzz]

Douglas I have 2 separate spheres.

[Douglas]

either way you can still do what you want, you just need to pick a master tip and set the sphere in each location with that tip before calibrating from it

-use master tip locate sphere position 1 telling it sphere did move
-calibrate what you need off that sphere location telling it no the sphere did not move, do not re-do the master tip it is done from step 1
-move sphere, use the exact same tip to set location, single tip telling it the sphere moved
-calibrate what is needed off 2nd location telling it the sphere did not move

you just basically always need to use the exact same tip when you tell it the sphere moved, you lost that somewhere along the way, hopefully I did not confuse that

if you used tip 1 in the first probe file to set sphere location 1 use tip 1 in that same probe file to set sphere location 2, then calibrate the second probe file from it

[plopperzz]

either way you can still do what you want, you just need to pick a master tip and set the sphere in each location with that tip before calibrating from it

-use master tip locate sphere position 1 telling it sphere did move
-calibrate what you need off that sphere location telling it no the sphere did not move, do not re-do the master tip it is done from step 1
-move sphere, use the exact same tip to set location, single tip telling it the sphere moved
-calibrate what is needed off 2nd location telling it the sphere did not move

you just basically always need to use the exact same tip when you tell it the sphere moved, you lost that somewhere along the way, hopefully I did not confuse that

if you used tip 1 in the first probe file to set sphere location 1 use tip 1 in that same probe file to set sphere location 2, then calibrate the second probe file from it

Ok i will try that tomorrow, thank you very much. Here is a simple breakdown of what i did.

I have two spheres, one with a vector of <0,0,1> (sphere 1)and another <0,-0.707,-0.707> (sphere 2), so 45 degrees from the z axis in the zy plane.

I calibrate tips 1,2 and, 3, from probefile 1,on sphere 1, they all work properly. Then i calibrate tips 4 and 5 from probefile 2 on sphere 2. For those tips x and z measured values are fine but y values are off by about 1.5mm.

[Douglas]

I'm not sure you need 2 probe files to do what you want, what made you go that route if it is all in the same wrist position?

[Douglas]

You certainly need 2 tool files, one for each sphere, but seems to me one probe file should cover it, or at least not seeing why not

[plopperzz]

Douglas my boss said he ran into this issue when he was programming and thats how he fixed it (or so he recalls) and tech support at CMMXYZ also said i need two probe files. One for each sphere

[Douglas]

what is the probe configuration, 5 tips i see but what are the tip vectors? there must be something I'm not understanding or you should only need one probe file, but will need 2 tool ID, one for each sphere.

I can take my 5 tip star probe and calibrate each tip on a different sphere all within the same probe file and as long as I set each sphere location correctly it works.

[Douglas]

i seriously think you misunderstood cmmxyz and they meant 2 different tool ID not probe file

[Douglas]

i have a 5way star with 3 wrist positions, A0B0 A90B0 A-90B0 giving me a total of 15 tips.
I use a different sphere position for each wrist position 3 different sphere location/orientation, but it is all in the same probe file and works great as long as I properly locate each sphere location with my master tip before I use it

[plopperzz]

Douglas I will make sure take some screenshots when I get to work in the morning so that you can see how things are set up.

Also, what do you mean by master tip, A0B0?

Nevermind, I just found a thread explaining the master tip.

[Douglas]

ok, there must be something I misunderstand... I thought it sounded like you had all 5 tips on the same probe build, but must be 2 different probe sets you are using. if you put a picture of your probes up I will see better what you need to do for sure

[plopperzz]

i have a 5way star with 3 wrist positions, A0B0 A90B0 A-90B0 giving me a total of 15 tips.
I use a different sphere position for each wrist position 3 different sphere location/orientation, but it is all in the same probe file and works great as long as I properly locate each sphere location with my master tip before I use it

Thanks for taking the time to help me! I was able to resolve the issue once you mentioned a master probe.

For anyone who finds this thread and has the same problem, here are additional threads I was able to find once I knew what I was looking for that helped

How to Calibrate Probe Using 2 Spheres

https://www.pcdmisforum.com/forum/pc...sing-2-spheres

and

What is a Master Tip/Probe?

https://www.pcdmisforum.com/forum/pc...ster-tip-probe


I ended up just building a probe named MASTER_PROBE with the medium force module and a 6 by 10 mm probe with the only tip being T1A0B0. I calibrated on both separate calibration spheres (making sure to change the calibration tool in the probe utilities window) using only this tip, and for each sphere I selected "Yes" when asked if it has moved. Then I swapped out the module for my star probe module and calibrated all of the tips using the appropriate sphere selecting the option "No" when asked if the sphere moved.

[neil.challinor]

OK, you can only use what you have I suppose.

[Douglas]

what sort of standard deviations are you getting on the master and the star out of curiosity?

[plopperzz]

Douglas Standard deviation on the master was 0.001 mm and for the star it was around 0.002-3 mm. Just had the CMM calibrated last Tuesday.

[Douglas]

Watch 4 digits calibrating in mm, there is a notable difference between. 0006 and .0014mm in my opinion, 3 digits won't show you enough.

Also you can have a perfectly calibrated machine and still get bad std dev in calibration due to probe build problems. Machine calibration is assumed to be good, that std dev is checking the integrity of your probe not the machine.

Make the next module you buy a standard force as suggested and make it your master and it will calibrate with lower std dev, more reliability locating spheres

[Douglas]

How many hits and levels are you using? I like a minimum of 13 hits on 3 levels

[plopperzz]

I agree. I have already started to bug my boss for a standard force module as well as a 6 way module. I use the same, and I've been running it quite slow lately.

[Radam3]

I'm bumping this thread for a very similar problem, instead of starting a new one...

I now have a need for the same "L- shaped" probe as the OP. So I have it built, and I can calibrate it on an angled sphere (0,-.707,-.707) I think I understand the use of the master probe to tie it to all the other probes...

My question is, we've always only used a 0,0,1 sphere for calibration. Once I tell PCDMIS my sphere has moved for the new angled sphere, using my master probe/tip, calibrate just A0B0 with it, and then my new probe with the "L" tip on the same sphere with out moving it, will all my other probes/tips that were calibrated on our original sphere in a different location still relate?

And what about next time I go to calibrate my whole rack on the original sphere? Just tell it it has moved again for A0B0 of my master tip and carry on as usual from there? Or is it tied to the tool used for calibration, so I wouldn't even need to tell it that because that tool is still in the same place?

I ask because the part is very large and is going to require multiple tips, with multiple probes to measure. All others were already available in our current setup, except for the features that are "under" the part and require the "L" shaped tip to pick up. They all obviously need to be related so I can report the part as a whole...

Thanks in advance,
The "FNG"

[Douglas]

if you are using the same master in the same wrist position to locate both sphere you should be ok. Just make sure you are telling it yes the sphere has moved when it is your intent to set the sphere location. I have no idea why pcdmis complicated the lingo so badly, why not just give me the function to 'SET SPHERE LOCATION' instead of silly questions if I've moved the sphere to make sure that is what it should do

the only reason pcdmis needs more than one tool file at all is so that the shank can be avoided, other than that the master probe is just setting the sphere location in machine coordinates, it would not matter which tips were calibrated of which sphere, as long as you use the master properly to locate both sphere you will be ok