Part 3 of datum features constraining degrees of freedom - datum sequence

In this video, we see how switching the datum sequence affects which datum features constrain which degrees of freedom

[@harikumar4757]

Sir, nice lecture.
Is this Datum B calledout on surface of cylinder or axis.
Also at 1:05 ,what is the gauge size if Datum B( RFS ) and B(MMC).How it is changing in both condition.kindly a replay.

[@davidslopsema4374]

Datum feature B is the pin. Datum B is the axis of the pin.

[@davidslopsema4374]

If datum feature B were referenced MMB, the gage would have a fixed size hole, but we don't have enough information on the drawing to calculate the size of the hole in the gage. As it is, with datum feature B referenced RMB, the hole in the gage is a variable size so that it can exactly surround the pin with no looseness.

[@harikumar4757]

@@davidslopsema4374 ok thankyou sir, for valuable replay