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This Position ...i cant measurment

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By [Fl...] ,
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[De...]

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Measure the four sides as planes and the four corner radii as cylinders.

For the first line of the callout make a profile characteristic and for the datum reference frame choose datums A B C and assign your tolerance of 0.2

Make a 'Maximum Result' Characteristic (Size - More - Maximum Result) and include all of these profiles.

The profiles are all being reported to the datum reference frame you put in A B C, so they are all being reported in a 'simultaneous result' as required.

For the second line of the profile since it is profile all over to itself with no datums we need to do a bit more work.

First create a Geometry Best Fit Alignment (Resource - Utilities - Geometry Best Fit)

Hit the select elements button and choose your features, the 4 planes and the 4 cylinders.

Next hit the evaluation constraints button, and make sure all the options are checked, this will allow the best fit to use all possible translations and rotations.

Now create an additional profile characteristic for each plane and cylinder, each one should use the 'geometry best fit' alignment in the datum reference frame and have a tolerance set of 0.1

The best fit will allow all of the cylinders and planes selected to be best fit as a group which should maintain there simultaneous requirement to one another while still allowing you to check the profile of each when in it is in its 'best fit' condition as a part of the overall pattern.

For the second group add a second maximum result characteristic and select all the 0.1 profiles.

This should allow you to check both profiles in your composite profile tolerance and provide one overall answer for each.
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[Fl...]

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Thank You for your great answer ,but i have the questions. In PC demis is the line scanning or perimetre scan for this profile...or elipse with four radius...in Calypso not is this??? And another questions is who i can put the datum reference for plan A ,B and C,where is this opțional???thanks again
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[De...]

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Calypso can do this using the curve option. I was not sure if you had the curve option or not. It requires a lot more explanation to handle this using curve than it does to just use planes and cylinders.

Also, any 2d curve only handles a 2d slice of the part, but to handle form error, perpendicularity, you would need to scan more than one line around the outside to give a true answer for profile.

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I am not sure I understand, however if you create a profile characteristic, you can specify your datum's in the lower portion.
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[Fl...]

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Hello again ,
Today i try and is ok, but in the drawing îs necessary toate put the tolerance in accordance with Y14 5 from 2009. I can search in the Calypso this ISO?
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[Ri...]

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As far as I know, there is no difference between ISO and ASME regarding the evaluation of profile. It is just the deviation of the measured profile to the nominal profile. The biggest difference is going to be in the DRF, and which evaluation parameters you use.
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[Ri...]

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I don't know much about PC-DMIS, but it looks like that ISO to ASME switch has to do with the DRF - not the evaluation of the Line Profile itself. There are big differences between ISO and ASME regarding Datum Reference Frames.

Here is text from an email that I sent just a bit ago regarding this very issue.

"Regarding Profile – there is no difference that I can find between ASME Y 14.5M and the ISO specification regarding Profile evaluation. The definition is as follows – “The profile deviation of a line is the maximum distance between the extracted profile (measured) and the nominal profile, perpendicular to the nominal profile.” There are differences between ISO and ASME regarding interpretations of unilateral tolerance zones, all-around principle, and multiple surfaces. They are only in how you interpret the tolerance block, not in regards to evaluation.

Now, where ISO and ASME are completely far apart from one another is that ISO works off the principle of independency. Which means that size and form and location/orientation are independent of one another. If you are using ISO to evaluate the diameter of a shaft with a standard tolerance of Ø20 +0.1 – that means that all local sizes(2 point measurement) must lie between 20.0mm and 20.1mm, and there are no regards for form or orientation. In ASME, size, form, and location/orientation are dependent of one another, so the same callout would mean that you have to take into account form and orientation – meaning that if the shaft was measured at 20.1mm that it could have 0 form/location/orientation error as it would not assemble if it did. In ISO they do have these same principles, but it is called the Envelope Principle (letter E with a circle around it). It means the same exact thing as in ASME, but in ASME it is implied by default.

There are also extreme differences regarding the evaluation/construction of Datums. ISO says that for straight lines or plane as a Datum that it is “The datum is the associated adjacent straight line or plane, evaluated by the Chebyshevian principle (or minimum zone principle) and parallel translated into the highest (material side) points or tangential features”. That’s a mouthful, confusing, and as far as I know no measurement software does/can do that. For the axis of a cylinder as a Datum “The datum is the axis of the maximum inscribed cylinder (or minimum circumscribed cylinder in the case of an outer element respectively). In both cases, the datum is the axis of the adjacent feature.” That part is similar to ASME, the only difference lie in that fact that ISO requires you to “probe” parallel to axis of the cylinder which means that you have to measure the axis of the cylinder fist before you can do that – very confusing. ASME requires you to use outer tangential for the Datums.

Having said all of that – you cannot change from one standard to the other standard in Calypso in the sense of a click of the button. You are in control in how you measure and how you evaluate the feature. However, there is a setting in Calypso in regards to ISO 5459 which has to do eliminating form deviations on the Datum and how the DRF axis is setup.

ISO also has the rule of invocation which means that if one ISO spec is listed on the drawing, all ISO specs are then implied (and there are a bunch). There is only one ASME specification.

Here is a list of important ISO specs that have to deal with GD&T:

ISO 286
ISO 1101
ISO DIS 1660 (this one is explicitly about Profile)
ISO 2692
ISO 5458
ISO 5459
ISO 8015
ISO 10579
ISO 14405-1
ISO14405-2
ISO 14660-1
ISO 14660-2


I hope that some of this information helps. Thank you."
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[Me...]

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Calypso is not PC-Dmis. You don't choose your standard like you do with Xact Measure in PC-Dmis. You need to evaluate it as Derek described, selecting your Datums and Material Boundaries (MMB) inside of the Profile Characteristic after collecting your data.

There is no difference in the evaluation, as Richard pointed out. The only difference between ISO and ASME may be in the reporting of the results. ASME reports 2x the max deviation from nominal as the result, and ISO reports the Min & Max deviation.
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[Fl...]

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Hello my friends,
Sorry for my inssistend...and for my bad english.i attached the photos and i din understand the next:
1 . I put the datum ( profile) when You see , and want to Tell me and is ok ,but i understand that îs the datum from the profil form and for the POSITION for to ABC datum ( the origin parte ,alignment) and for the POSITION i put the nominal but the actual îs complet diferent... But the total of the form profile îs put only 0.3 and i dont understand...i think that the position îs calculated with the diferent from the nominal ...You can see the photos for more info....
2. I put for calculated this dates the corners( radius) with cylinder but with one circle...îs ok or îs necessary Two circle for this cylinder?
3. In the profil Datum i put one result( see the photos) îs ok or îs necessary another?
4. In the photos You can see the nominal from the program ( i put the correct nominal) and in another photos ( when îs the raport measurment from the parts ( with Red) îs another calculated valuri ...why? This îs my questions and If You can help my ...im very happy.,thanks again

IMG_20190227_164438.jpgIMG_20190227_164451.jpgIMG_20190227_164438.jpgIMG_20190227_143905.jpgIMG_20190227_141439.jpgIMG_20190227_111004.jpg

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[Fl...]

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For the first questions You can see the photos 4 and 5 . Cylinder fata jos = profile 18 ( in cylinder fata jos î put the correct nominal position...
For 3 questions i attached the photos 6.
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