GDT Question

[[Ch...]]

What do you guys think the tolerance if for the 25mm dimension on this snip?

Where I'm struggling is finding the clause or snip in Y14.5 that proves this.

[[Ro...]]

A basic dimension has no tolerance, regardless of what the block tolerances are. It needs to be defined by a FCF or it's incomplete.

The FCF shown defines orientation, but not size.

[[Ch...]]

I understand. But I'm trying to find a way to prove that using the standard.

Proving a negative is basically impossible; So I will need come up with a counterfactual as proof.

Anyone have any ideas?

[[Ch...]]

Only thing I note here is :

The parallelism clearly applies to the CL, I think we can agree, and therefore is only controlling orientation of the feature in concern.

There may be something else controlling it's size (profile general note, etc.)

Therefore it may be legit - probalby not the best or preffered way to tolerance it, but doable in Calypso anyway.

[[Ch...]]

Much appreciated guys.

Luckily, there isn't a "how do I measure this" question that came up. My only goal is to find the most clear/effective verbiage to communicate that .1 is not controlling the distance.

[[Ro...]]

This is from the 1994 standard. It hasn't changed. The whole premise of GD&T is based on basic dims and FCF's. They're speaking a different language.

[[Ri...]]

Someone is using parallelism in place of Profile.