Restrained Condition

[Rwelch9]

If you were to dimension a drawing and the part had to be inspected in a restrained condition.

For example sitting against A Datum Simulator ( ground plate for example )

if the part had 4x holes ( BCD) which the part got clamped thru to restrain the component .

How to you then check the 4x holes to the rest of the part or any feature that is compromised due to clamping whilst inspection.

can you just as an ( F ) next to the dimensions and check them in a free state ?

The component i have i would like all the critical features to be checked clamped as the part would be acting as a functional part.

However whilst the part is clamped a few sizes would not be able to be checked . ie 4x holes

Thanks

Ross

 

[cr7]

I don't know the answer, but out of curiosity, is it plastic? Thin stamped metal?

 

[chez311]

I would question why you need to measure a bolt hole while restrained. If any feature which is blocked by the specified clamping method it may be acceptable to check it with an alternate clamping method (ie: use clamps instead of a bolt), though of course the exact distribution of forces will be different so there will be a tradeoff - you would have to do your own analysis to determine that (a) the alternate method provides the same clamp load and (b) that the tradeoff is acceptable, which may not be the case for features very close to where the clamps are being applied. If it was a customer's print I certainly wouldn't go that route without verifying it with the customer first. If that won't work then CT scanning would be your only option. This all seems like extreme overkill though to measure a bolt hole while restrained.

can you just as an ( F ) next to the dimensions and check them in a free state ?

Yes however know that application of the Free State Symbol constitutes an exception to Rule #1 in Y14.5-2018. In 2009 it was implied that application of this symbol may have overridden Rule #1, but it was not explicit (F symbol was applied to features subject to free state variation - features subject to free state variation were an exception to Rule #1).

If you do not desire to override Rule #1 and maintain the form control it provides, but still desire to measure a feature when not restrained a note similar to the Y14.5-2018 fig 7-27.