Lmc

[Jignesh]

Maximum material condition:
1. For internal diameter: Bonus tolerance=( measured value- minimum diameter) + True position tolerance.

2. For external diameter: Bonus tolerance=( maximum diameter- measured value) + True position tolerance.


CMM can calculate Least material condition itself. However, can someone please define manually how to calculate bonus tolerance in Least material condition as I showed for MMC above? I have been little confused about it.

[JEFMAN]

Is that help ?
https://www.gdandtbasics.com/least-material-condition/

[Roberto]

Very useful info @ JEFMAN
LMC is not too common. To be honest I don't remember checking a position of a hole or a pin with LMC

Allez les Bleus!

[JEFMAN]

Gracias, Roberto

[bfire85]

We have a part that requires LMC on an ID of a stem. It was explained that they want to control wall thickness between the ID and OD, but make sure the hole is with position to Datum B. Rare, but it happens.

[Schlag]

I would look at it more like Bonus TOl. + Feature Control Frame TOL. = Actual TOl. Yeah, the end number is the same but if we were talking in a conversation and you said how much "bonus" tolerance you had I would assume that you would then add that to the actual TOL. Just trying to keep the verbiage correct.