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I just looked and they don’t need to be on the same plane. ASME Y14.5 requires only that features reference the same datum reference frame—not that they lie on the same plane—for the simultaneous requirement to apply (Section 7.19). “A simultaneous requirement applies to position and profile tolerances that are located by basic dimensions related to common datum features referenced in the same order of precedence at the same boundary conditions. In a simultaneous requirement, there is no translation or rotation between the datum reference frames of the included geometric tolerances, thus creating a single pattern. Figures 7-46 and 7-47 show examples of simultaneous requirements. If such an interrelationship is not required, a notation such as SEP REQT should be placed adjacent to each applicable feature control frame. … This principle does not apply to the lower segments of composite feature control frames. … If a simultaneous requirement is desired for the lower segments of two or more composite feature control frames, a notation such as SIM REQT shall be placed adjacent to each applicable lower segment … Simultaneous requirements are not applicable and cannot be invoked by notation on single-segment or multiple-segment feature control frames when the datum references are different, the datum references appear in a different order of precedence, or the applicable material boundaries are different.”

That's how I was interpreting it as well, however I didn't see anything in the standard that says the features have to be on the same plane. That would be great as it would cut down on programming time a little. What section is that listed in so I can protect my behind if need be?

a fully constrained DRF is not cause to eliminate Simultaneous Requirement. In ASME Y14.5, the simultaneous requirement applies by default when: Multiple features Share the same datum reference frame And are controlled by separate feature control frames, can be a different set of holes but lie on the same plane but share the same datums and datum order. Without an explicit modifier that breaks simultaneity as in Separate Requirement.

If I am reading this correctly, it almost looks like the left and right flanks have slightly different slopes. The tolerance for FHbeta is 18 microns, but on the left flank, you have to give it a nominal offset of -32. I couldn't tell you the reason for the specification, but without further information, that's probably be my interpretation.

Hello Isaias, I just tried this and it worked fine on my computer, at least I believe it did. Which plots weren't you seeing?

For the profile, it would depend a bit on the part itself. You can do surface profiles (most) standard geometries, though there is a bit of a trick to it with the old GD&T engine (see https://portal.zeiss.com/knowledge-base?id=868503). Additionally, you can do it with individual points, but it is significantly harder (see https://portal.zeiss.com/knowledge-base?id=2495545).

Well, in this case the datum structure seems to be fully constrained right? Simultaneity makes sure that all features in a callout move together rather than separately when there are unconstrained degrees of freedom, but it looks like all of them are constrained in this example.

Starting to use the new GD&T engine instead of the classic. So concerning the accompanying callout - Because the callout is basically the same thing as having 8 individual callouts all with the same Datum Reference Frame, do all 8 holes need to be checked simultaneously?

Very similar answer to Quang Tran. I currently have 60 different stylus system identifications that get used on our machines. My naming protocol is simply what type of head it is, and then a number. Example: XT 001, XT 002, etc. All of the probes work on any machine with an XT head (interchangeable) and there’s no need to worry about getting probes mixed up. For the most heavily used stylus systems I make two systems exactly the same (one for each machine) and call them both XT 001 for example. Works good.

Hello, I am currently running two machines and I named the probe system & stylus the same across both machine. There isnt a problem when program on one and open it on the other. The program just run normally if the name matches.

Curious as to how others with multiple CMMs are naming their probes? I have a majority of programs stored online for rev control and that is working great, however every time there is a rev change, I have to go to each individual machine and update the probe names per that machine when I download the program to the machine. We have a commonly used 3-4 probes that are built exactly the same @ each machine (probe dia / length / etc). Are there any issues with naming those the exact same to remove the step of me needing to update @ every machine? I assume calypso knows/ is set up to use the individual probe data from each machine. Current Naming looks like this Machine 1: Small_Spline_Star Machine 2: small_spline_star Machine 3: SMALL_SPLINE_STAR etc etc

I understand. I have to use PCM. There are 5 groups 9 sizes and 45-part numbers. All in 5 separate programs.

Biggest problem is that the machine models are not correct... there is about 6" of extra granite surface... I have take great time to mimic my actual machine on my offline machine down to movable chuck jaws. Every version until now, the work areas and models (programs) come in exactly the same. Now, they are in the machine itself. I have 4 older prismos (oldest one is from 1997) with a 1200 1800 1000 volume. Did a simple test.. top of platter is rough -37" from machine zero on my machine.... loaded my platter cad model, translated down that much...its in the machine. Reached out to Zeiss no help so far.

@Christian Marti I don't know if he checked the unit underneath. He did hook up a monitor to the controller, looking for something but not sure it was conclusive.

Is it at all possible to use a search distance for each individual point? Or maybe take one point that you know will touch in a location every single time with search distance. Then your individual plane points can reference back based off where that search distance point was taken? I think I understand what you're asking, but if I don't then disregard that message

Hello, I was attempting to do a report containing parallelism on a car roof. Functionally, how is that done in the software? I followed the instructions but apparently I am missing something. Thank you.

hey marco, to clarify - you want a nominal surface point with dn check instead of a deviation label on the surface comparison? import gom import numpy as np gom_part = gom.app.project.parts[0] label = gom.app.project.inspection['Surface comparison 2'].deviation_label['Surface comparison 2.1'] coord = np.array(label.data.coordinate) normal = np.array(label.data.normal) x, y, z = coord.reshape(-1) nx, ny, nz = normal.reshape(-1) gom.script.cad.show_element_exclusively (elements=gom.ElementSelection ({'category': ['key', 'elements', 'part', gom_part, 'explorer_category', 'nominal_part']})) ##nominal surface pt nominal_surface_pt = gom.script.primitive.create_surface_point ( name_expression='Point_from_label', point={'interpolated': True, 'normal': gom.Vec3d (nx, ny, nz), 'point': gom.Vec3d (x,y,z), 'target': gom_part}) ##make sure its attached to cad surface gom.script.cad.adapt_elements_to_cad ( elements=[nominal_surface_pt], normal_from_cad=True, position_from_cad=True) ##mp MCAD_ELEMENT=gom.script.inspection.measure_by_intersection_with_mesh ( elements=[nominal_surface_pt]) #check MCAD_ELEMENT=gom.script.inspection.inspect_dimension ( csys=gom.app.project.nominal_elements['system_global_coordinate_system'], elements=[nominal_surface_pt], nominal_value=0.0, nominal_value_source='fixed_value', type='normal')

Thanks that's what i needed. How did you find the "gom.script" functions? the print(__doc_) just returns none for it

https://www.gdandtbasics.com/composite-position-vs-multiple-single-segment-tolerances/ I'm pretty sure ASME requires at least 1 datum for position. For example, a cylinder with a position to the bottim surface plane would essentially be an evaluation of perpendicularity.

To see which alignment corresponds to each index, simply type: print(gom.app.project.alignments[3]) (just change the index number). • Index 0 → always the original scan position • Index 1 → usually the pre-alignment • Index 2, 3, … → user-created alignments in the order they were created.

Hello Darci, for composite/Multiple Single Segment position, I recommend reviewing Faro.com's and GDandTbasics.com's material on this topic. I haven't seen them without datums however, so I can't help with that. Sorry!

Hi Justin! If I understood this simple script do exactly what you have to do. This is one way to do it. # -*- coding: utf-8 -*- import gom page_in_report=[] for page in gom.app.project.reports: print (page) page_in_report.append(page) gom.script.manage_alignment.set_alignment_active (cad_alignment=gom.app.project.alignments[2]) gom.script.report.update_report_page ( pages=page_in_report, used_alignments='current', used_digits='report', used_legends='report', used_stages='report', used_units='report')

Hi Nanno! My goal is to take the vector and the position in the 3dview of a dn label then create a normal deviation label in the same position of the dn label. Do you know the right way to do it?

I have a family of parts. The geometry is the same, but each P/N changes size in all axis. My base alignment uses (in-part) two angled planes to construct a symmetry plane for X Each of the parts, the two planes have a different angles and XZ coordinates. I have those variables in a para file for the first part. The problem is, I don't know the best way to move the points with PCM as the planes change. Do I have to have XYZ for each of the 4 points for each plane? Or is there a simpler way?

@DWC Since you are online at the moment, can I ask you another question? What does the composite tolerance mean? I am not very familiar with them either, and I am even more confused since there is no datum.