In Machine Inspection

[JB7280]

For you guys who have used both, which do you prefer, The Cimco, or Renishaw add-ons for Mastercam?  

 

Also, can someone explain the difference between inspection plus, and productivity plus?  I think I've had them backwards for years.  

[CEMENTHEAD]

I would not recommend inspecting a part using the same machine that made said part. Been there, done that. 

[Jake L]

Might be worth checking out this thread:

 From what I remember there was a lot of good stuff in that one.

[Aaron Eberhard]

For 90% of people, the CIMCO add on will be way less setup pain and get you there faster, cheaper, and easier utilizing the I+ macros already set up on the machine.  For 10% of the people, I haven't seen anything else on the market give the ease of use of setting up complex logic (multiple nested If/Then/Else logic) like P+ can do. 

Inspection+ are the macros that ship with the probe on your machine.  If you use the GoProbe app on your phone (or the Renishaw manual) to enter, say,  G65P9901M2.D0.5S54. to probe a .5" bore, that's Inspection+.

Productivity+ was developed by Renishaw as a stand alone program (yes, you can buy just P+, not integrated into Mastercam!).  The problem was they can't trust the I+ macros to be the same everywhere, that no one edited them, and that they could support all the logic they wanted so they developed the P+ macros.   You'll have two sets of macros loaded onto your machine, two sets of calibration data in the parameters, etc.  P+ coming out of Mastercam will ONLY use P+ macros. 

[Matthew Hajicek - Singularity]

Whether or not inspecting on the same machine that made the part will meet your needs, will depend on your needs.  If you want to do it properly, you should meet the same bar as for other measurement methods; get your machine laser / ballbar calibrated, do a measurement repeatability and uncertainty test, etc., and make sure that your uncertainty is less than 1/10 your tightest tolerance.  You can include measuring a gauge block / pin / ring as part of your inspection process to warn you of any calibration drift, thermal expansion issue, or other problem.

[JB7280]

17 hours ago, CEMENTHEAD said:

I would not recommend inspecting a part using the same machine that made said part. Been there, done that. 

 

15 hours ago, Matthew Hajicek - Singularity said:

Whether or not inspecting on the same machine that made the part will meet your needs, will depend on your needs.  If you want to do it properly, you should meet the same bar as for other measurement methods; get your machine laser / ballbar calibrated, do a measurement repeatability and uncertainty test, etc., and make sure that your uncertainty is less than 1/10 your tightest tolerance.  You can include measuring a gauge block / pin / ring as part of your inspection process to warn you of any calibration drift, thermal expansion issue, or other problem.

I 100% agree, that there are issues with inspecting the part, on the machine that made it.  I've expressed that to management, and the engineering department is still being pushed to inspect parts on the machine.  So, from this point, we'll just do what we can to inspect what actually makes sense.

[heavychevy2155]

We are using Cappsnc here at Blue Origin.

[Aaron Eberhard]

1 hour ago, heavychevy2155 said:

We are using Cappsnc here at Blue Origin.

I haven't heard of 'em..

Their aircraft wing/surface panel tech looks really cool!

[heavychevy2155]

It's the software we use to program all of our probing, both setup and in process inspections.  We run the probing cycles through Vericut to make sure there are no errors and we have had pretty good success so far.

[cncappsjames]

On 4/15/2024 at 11:30 AM, CEMENTHEAD said:

I would not recommend inspecting a part using the same machine that made said part. Been there, done that. 

It can be done effectively... it just has to be approached in the right manner.

The #1 issue with inspecting a part on the machine that produced it isn't that the machine is checking itself, it is that the connection between the coordinate system that manufactured the part and the coordinate system that is inspecting the part isn't broken. You MUST break that connection in order to get an accurate measurement.

On a 5-Axis machine with a FANUC control, that means having G68.2, G54.4, machine parameters set correctly, AND the probing software that supports probing with those functions active. Don;t have ALL those things squared away and there WILL be trouble in paradise.

[crazy^millman]

Well I learned last week a major very respected builder does their machine calibration services using levels and squares not an interferometer. The issue was our programming process used was called into question. Print states one thing, but then 20 other things state 20 other things. Print is the authority unless some inspector decides no they want a +/-.0005 on a part with a +/-.010 wall thickness on the print. Or a 16 finish when the print calls out 125 and add hundreds of hours of processing time to the project. Cut 6 pockets the same exact way and 2 of the 4 are acceptable, but then as we get to longer tools the deviation between the two tools doing the work became greater. Root cause analysis looks into the root of the problem. Machine has not been calibrated in over a year. I happened to be onsite when they were going through the machine calibration and what an eye opening experience that was. Levels and squares with a spindle gauge. No external way to verify the machine is going where it is told to. This is the extent of the full volumetric machine calibration process. I called James and make sure I hadn't lost my mind and was an internal interferometer installed on the machine in question I was unaware of. NO NOT ONE HE SUPPORTS and he was unaware of one being installed either. We both agreed even it one was that at someone point would have to be calibrated.

Why is this an important topic of conversation and how is it related? Here is some light reading for those that take their jobs seriously. All the hates keep on hating.

Machine tool calibration: Measurement, modeling, and compensation of machine tool errors

Quote

Abstract

Advanced technologies for the calibration of machine tools are presented. Kinematic errors independently of their causes are classified into errors within one-axis as intra-axis errors, errors between axes as inter-axis errors, and as volumetric errors. As the major technological elements of machine tool calibration, the measurement methods, modeling theories, and compensation strategies of the machine tool errors are addressed. The criteria for selecting a combination of the technological elements for machine tool calibration from the point of view of accuracy, complexity, and cost are provided. Recent applications of artificial intelligence and machine learning in machine tool calibration are introduced. Remarks are also made on future trends in machine tool calibration.

There is too much to quote that is important.

[crazy^millman]

On 4/15/2024 at 10:30 AM, CEMENTHEAD said:

I would not recommend inspecting a part using the same machine that made said part. Been there, done that. 

Yeah because of what I just mentioned above. When the above is done with a NIST Traceable artifact then the process is not just using the machine to inspect the part it is the process that is support the device which happens to be a CNC Machine. The device collecting the measurements doesn't matter at that point since the process to ensure what is collecting the measurements is validated and verified all is good. A CMM that is not correctly calibrated is not better than a machine tool that is not calibrated correctly either.

[Jake L]

On 4/16/2024 at 7:20 AM, JB7280 said:

 

I 100% agree, that there are issues with inspecting the part, on the machine that made it.  I've expressed that to management, and the engineering department is still being pushed to inspect parts on the machine.  So, from this point, we'll just do what we can to inspect what actually makes sense.

Ask the pushers if they want the machines making more chips or checking parts.

Maybe your management team thinks differently, but my management team always wants to make more chips. Some of them may not understand much about manufacturing, but they all understand more chips = more parts = more $$ 

...food for thought, a CNC can do a CMM's job but not visa versa.

[cncappsjames]

Adding non manufacturing time adds TAKT time. Added TAKT time = higher cost. 

That said, WIP = Inventory. Inventory = Money. Money = Taxation

Parts in inspection = WIP therefore there's a cost no matter where the part is within the factory. If you can integrate and automate processes you can bring down the labor component of part cost. 

"There are no perfect solutions, only compromises." Thomas Sowell

[Matthew Hajicek - Singularity]

There's also less handling if you can get in-machine-inspection working right, reliably, and efficiently.

[cncappsjames]

Also, if you've got the inspection stuff squared away, it's easy peasy to generate reports, csv data, etc...

If you can imagine it, you can format it, and generate reports. 

[Newbeeee™]

@James - great comment ref your #1 above.

I would also add the obvious that part shape material and workholding comes into it too. Measure the part xxxx on!

Unclamp the part and distortion....

And Ron - Ref many Inspectors and their job choice...."If you can't do it, View it"