GDT Profile, FF vs Feature & Best Fit

[[Ze...]]

Hello smart people! 

I'm trying to get up to speed on the new GD&T engine and profile characteristics. I have a couple of questions...

1) I get different results if I use the feature itself (a cone in this case) as opposed to using a freeform surface created from the cone in the GDT profile characteristic. Which is the correct way to inspect profile?

2) It looks like you can't use an alignment in the GDT profile characteristic. For example, I used to use a best fit alignment created from a bore pattern in my profile characteristic to use   a hole pattern as a tertiary datum. How would I do that in the GDT profile characteristic?  

Thanks as always for your help! 

BTW... I'm using Calypso 2024

Edited 3 hours ago

[[Ri...]]

I would generally prefer to use the standard geometry if I can - mainly because I can filter/outlier elimination if needed. 

You can use an alignment inside of the GD&T engine, but you have to switch over to "Loose". 

[[Ze...]]

Thank you, Richard, You're always very helpful. I really appreciate it! 

Something about checking "Loose" makes me feel uneasy in measurement software. lol

I'm measuring some fairly tight profiles and am trying to coordinate with outside vendors on results, so I'm really trying to make sure I'm doing things as accurately as possible. 

Does Calypso 2025 have the same behavior in the GDT profile? I want upgrade but am holding off as there seems to be some bugs still being worked out in 2025. 

[[Ze...]]

Looks like Common Datum solves my alignment question about bore patterns. 

[[Ri...]]

Yeah, the name Loose probably needs to change - lol. 

Two big changes from 2023/2024 to 2025 are the fact that we can do FFS inside of the new Profile, and now you can create an Alignment from the DRF that is created inside a GD&T characteristic. 

The new GDT Profile in 2025+ will have virtually all of the tools that you need, you can even do unequally disposed profile or UZ profiles (the software automatically sets it up based on which standard you are using).