If you are a Govt. contractor, most of your drawings are legacy and call out 1982 edition of 14.5. It would be nice to have that as an option.


Yes it would. I have many different customers that I create programs for. I prefer to use Xact measure outputs.


The new PC-DMIS 2021 version is not capable of opening legacy programs using older requirements, The software creates errors when an older PROGRAM and that it does not correlate to the ASME Y14.5 2018. We are an Aerospace manufacturing company and we are customer (End user drawings) driven. 95% of all the programs are legacy and meet the drawing callout to the older ASME Y14.5 1994 OR 2009 and the GD&T to match. NO more TP to a point, a plane, concentricity and or Symmetry. there may be more.

The software must be backward compatible, maybe they can add a fuction that allows the program to be created or to run on the applicable ASME Y14.5 . i have brought this issue up to Hexagon and its over a month and I have not recieved a solution.


This definitely needs to become an option going forward! 

Hexagon seems to want to ignore this and I do not know why.

I'm now in addition to CMM programing I have a CT scanner GOM that I'm programing. It has Y14.5 2018 and no other options as well.

This is causing problems with profiles and the constrained least square not correlating with CMM or any vision systems.

So everyday is a challenge. Also fit to datums does not work with the GOM software. So it requires an alignment like PCDMIS was before Exact measure.


This would be more than useful to us with our out of date customers still using as far back as ASME 1994 on their drawings


Yes most of my prints are 1994. But I still have 2009 & 2018 on a few of the newer prints. I would hope that our customers know and understand this is something that we have no other options or control over.

Just wish that software companies would give us the options needed.


I am glad to see this getting at least 12 votes now.  It is beyond me that this has to be asked for when the whole purpose of metrology software is to "measure and evaluate" and as stated, repeatedly, by several people here, prints are not 2021.  The great majority of prints have GD&T for standards as far back as 1982. The worst part about not having the ability to select prior revisions of a standard or support prior commands to a standard (right or wrong) is that we arbitrarily rended existing measurement routines dimensionally incompatible as customers upgrade PCDMIS versions.
We must be able to report dimensional information to the specific standard and not just pull the plug on something as relevant as that.

Absolutely Necessary! Not asking, requiring!!!

Not 1982. 1994 yes.,

There appears to be some misunderstanding.  Whilst the newer Geometric tolerance command is more restrictive than the feature control frame (XactMeasure) command that it replaced, this is due to the greater level of intelligence it employs.  XactMeasure employed very little intelligence and performed very minimal validity checks, leading to many mistakes and misinterpretations being allowed.  It never claimed to be "fully compliant" to any particular version of standard (ASME or ISO) and offered varying levels of support depending on which version of PC-DMIS you were running and which type of geometric tolerance was being reported.  For example the 2013 help file says this...

Information on FCF Dimension Calculations

Information on FCF Dimension Calculations

PC-DMIS and ASME Y14.5M-1994

  • PC-DMIS GD&T follows ASME (ANSI) Y14.5M-1994. The mathematics for this standard are described in "ASME Y14.5.1M-1994 Mathematical Definition of Dimensioning and Tolerancing Principles". This standard is similar to ISO 1101. The main difference is that Y14.5 requires Position datum fitting to find the candidate datum reference frame that minimizes the deviation of the considered feature. PC-DMIS allows the user to turn this off with the Fit to Datums check box.

Profile Calculations

  • In v4.2 and higher, the registry setting UseISOCalculations, found in the Options section of the PC-DMIS Settings Editor, can be set to 1 to report profile as two times the maximum deviation. This setting only affects Profile (not Flatness). Also, when the GD&T Standard on the Advanced tab of the GD&T dialog is set to ISO 1101, the Profile reports two times the max deviation and formonly Profile ignores size.

  • In PC-DMIS 2009 and higher, FCF Profile with formonly takes into account size when UseISOCalculations is set to 0 (ASME) or the GD&T Standard selected on the Advanced tab of the GD&T dialog box is ASME Y14.5. This is also true for legacy Profile formonly. A new registry entry called UseSizeForProfileDimensions in the Option section of the Settings Editor, lets you revert to the V42 and earlier behavior for legacy profile dimensions only. This registry entry defaults to 1 (TRUE), so you must use the PC-DMIS Settings Editor to change it to 0 (False). If set to 0, legacy Profile formonly will ignore size. However, the FCF profile will always take size into consideration even when this entry is set to 0 if the GD&T Standard is set to ASME Y14.5.

Some Calculation Differences

  • Legacy dimensions for roundness such as a Location dimension's RN line or a legacy Circularity dimension, are computed using the Least Square solution. On the other hand, FCF dimensions for roundness (Circularity and Cylindricity) in version 4.2 and higher are computed using the Tchebychev algorithm (min/max) as required by the Y14.5 standard. Because of the change in calculation, Circularity and Cylindricity FCF dimensions will generally compute to a slightly smaller value than their legacy counterparts.

Form Calculations

  • FCF dimensions in PC-DMIS 4.2 and later support the Y14.5 definitions of Circularity and Cylindricity.

  • FCF dimensions in PC-DMIS 4.3 and later support the Y14.5 definitions of Flatness. FCF flatness uses a Tchebychev (min/max) algorithm. Legacy flatness still uses the LS method. FCF flatness generally gives a somewhat smaller flatness value than the LS flatness. This is independent of the UseISOCalculations registry setting.

  • FCF dimensions in PC-DMIS 2009 and later support the Y14.5 definition of Straightness when using FCF dimensions.

  • Legacy form dimensions still calculate the least squares form.

A Note on Parallelism Evaluation

  • The evaluation of parallelism is 3-dimensional regardless of the workplane or the feature being dimensioned.

Replacing XactMeasure with the Geometric Tolerance command in PC-DMIS 2020 R2, allowed us to truly claim compliance for the first time.  By that I mean that we claim to prevent users from creating Geometric Tolerance commands for GD&T that is not compliant to their selected standard.  Previously, users could pretty much create any call out they liked - compliant or not.

As for people making the statement that they are not able to measure parts relating to the 1982 or 1994 versions of ASME anymore, I have to disagree.  Everything I have mentioned above applies only to XactMeasure and the Geometric Tolerance command.  There were no changes made to legacy dimensioning.  With legacy dimensioning, the onus is on the user to interpret the GDT correctly and to create alignments and dimensions accordingly in order to validate the drawing requirements.  You can therefore use legacy dimensioning to validate parts that reference older versions of the standards - this has always been the case.

Whilst we do have it on our roadmap to allow users to select a particular version of a standard, there is no definitive release date planned as of yet and we would not support any further back than ASME Y14.5 1994.  The main differences between 1994 and the currently supported 2009 version are the change to a single value for profile, the introduction of the translation, tangent plane and dynamic profile modifiers, the removal of candidate datum sets and the adoption of the constrained L2 math fitting.  Currently, users wishing to use the older, two value method for profile reporting can use legacy profile to achieve the desired output.

I cant understand the hesitation to make the Software backwards compatible, this request has nothing to do with the math and or the greater intelligence it deploys. This is due to the contractual adherence that we as the manufacturing and inspection entity MUST  be compliant to " THE PART DWG", the Drawing dictates what ASME Y14.5 to apply on each part - inspection it has nothing to do with what ASME version has been released today. The latest version of ASME is ONLY applicable to new parts being designed and released, these new parts & Drawings are so minimal that we (the manufacturing industry) will not see these newly designed parts that would fall under the new ASME for over a decade after all the testing has been done and approved for production.

Hexagon, this is not a request, this is a requirement that needs to be met.

Every time I try to open a CMM program that contains GD&T OR ALIGMENTS under an OLDER  & different version of PC-DMIS that adheres to an older ASME version, I get the errors. The newer version wants to convert into a "TEXT" whatever it doesn't accept under the latest changes, UNACCEPTABLE!

I remember when I was with Hexagon this was kind of being discussed or under development. Now that I am a key user for automotive, aerospace and defense, it would make sense than before. what we look for is, a drop-down which has different standard types, from 1994 to 2018 (per se.) to allow the user to choose what they would like to report to without changing anything else. saying that, I almost on daily basis have to report for both 1994/2009/2018 as we have all sort of drawings from different customer base all over, and pc-dmis allows always to do that with different versions installed in my PC and sometimes, I change the registry as described above in the help file or report via the legacy except for pattern of holes as we can't do that with legacy . As I am certified for ASME SGDTP, It is very easy for me to convince the customers of mine in case of  any minor discrepancy and they are always happy to discuss that and understand. so it comes to both ways, Hexagon to implement  this idea and user to explore the options described above or have multiple versions of pc-dmis and choose to run by choice of  drawing, But if the expectation is, creating a program with newer version and expect it to support older version of math does not sound logical to me as I have seen and experienced it wont work, but explore other possibilities as described.

A drop down with options is all we are all asking for.

We in the Aerospace industry (which I have been working for the last 30 years) have the majority of production contracts for over 10, 15 or even 20 plus years, the customers are not small Primes, we are talking about Major industries that will not go back and change a drawing that has been released and distributed over multiple suppliers and used for over 20 or more years, and now I am going to ask for an updated/revised drawing so they can change it to meet the inspection software that cant inspect using the applicable ASME?  I am sure they are aware of the revised ASME Y14.5 TO 2018.

A drawing change request is no small task, even on minor discrepancies due to drawing error as it affects design, manufacturing process and or dimensional errors, but not due to a limitation from our inspection software. They are just going to change to a supplier that can and possibly loose contracts worth much $$$.

I think Hexagon may start to loose PC-DMIS user, they may not want to upgrade to newer versions of PC-DMIS.

A drop down is a valid request and I would support that for sure. 

Dear Neil,  I am not sure if I still remember your mail id, I have been involved in this process of reporting as per many standards for few years now after I am out of Hexagon, I was user even before way back in 2000-2005, we don't have lot of options to report GD&T that time, 

But now, under Production running at full flow-, there are lot of factors involved right from purchasing, contractual agreement, supplier base with different versions, pressure from stake holders and many of them don't understand what datums are in many cases with all due respect and it is not easy to educate many of them, with so many factors involved an additional of drop down in pc-dmis to report as per different standards of ASME/ISO is the mandatory requirement of the time. itself and this will help many of the users to avoid confusions and it makes good sales pitch for pc-dmis as you can show that all standard types can be supported and probably would be the only software to do so in long turn, and this is definitely a valid request. 

As I previously said, we are aware of customers need to support different versions of the ASME and ISO standards and have it on our roadmap.  We are currently working on the changes required to allow a more granular selection of ASME or ISO standard by year - for example ASME Y14.5 - 1994, ASME Y14.5 - 2009, ASME Y14.5 - 2018.  However, this is not targeted to be released any sooner than PC-DMIS 2023.2

Note: The new math for datums is applicable as far back as ASME Y14.5-1982 since earlier releases of ASME had no mathematical definition.

What's the status of this request? I had a P&W customer visit and requested for multiple legacy parts to be moved into our facility, all of these part numbers are with 1990 - 2010 release revisions Drawings and most likely the applicable GD&T will not be in par with the latest software release. We have not updated our PC-DMIS from 2020 R1 because of this issue. 

Is Hexagon going to place a drop down with a choice of the ASME Y14.5 VERISON to choose from when creating or running a program?


As I stated in my previous comment, the GD&T team are currently working on allowing a choice between ASME Y14.5 1994, 2009 or 2018.  It is not as easy as "simply adding a drop-down", it requires changes to the rules that dictate which options are available depending on the year referenced and adding support for the old, two value profile calculation for 1994.

Once the GD&T team have added this new functionality to the GDT library, we will implement it in PC-DMIS (currently targeted for 2024.2)

@neil Chandler Thank you to all who are working on getting this request done. I posted this 4 yrs ago and never thought it would happen. We are in the process of updating to 2023.2 

side note: I know that in legacy you can achieve the proper results based on the standard, but with as many users of PCDMIS it would be impossible for everyone to fully understand what settings, alignments ect. that you would have to change. Also some of them are global settings and this would require you to change them based on the current part that you are inspecting.

And in a production environment with CMM operators not programmers keeping track of what to change and then the training of operators would be a nightmare to manage. Where I currently work we run hundreds of parts a day.

Again keep up the great work.