Measuring T.I.R. & Roundness

[bburch]

We are having some disagreements about how to measure t.i.r. and roundness using manual methods. Can someone please explain, in detail how to perform these measurements using manual methods(i.e. V-blocks, indicators, etc.)?

 

[alexit]

Runout is V-blocks and one indicator, TIR is V-blocks and many indicators (or measured at more than one point.) Roundness is manually considered same as measured runout, but not true because it is dependent on the axis, which you cannot have with v-blocks. A perfect cylinder (0.000 round) measured off-axis will result in poor runout and thus a (inaccurate) poor roundness too.

For our shafts we specify runout and TIR for the floor, and bring the part to inspection dept using form measurement machines for roundness and cylindricity...

 

[bburch]

Much appreciated.