diameters

[kass_b]

Measuring an inside diameter as a cylinder. Yeasterday readings were good more of same order came in this am, reset up everything was good. All of a sudden readings are off. Rechecking these with inside mics, only on 1.751 diam cylinder is constructed version 3.73mr3 any aswers for this Thanks

[Wes Cisco]

Start with the basics, are the parts clean? Did you do a qualification check on the probe tip(s)?

[kass_b]

Recalibrated at start cleaned probe. Using least squares, constucting cylinder. 32 hits total .001 tolerance.

[craiger_ny]

What are you verifying them with? 2 point contact bore gage? 3 point contact? Are they round? Are they tapered? Do you drink beer? Have you evaluated the individual circles for roundness and size? Are there any surface annomolies (what is the finish like)? What are you wearing right now?

[kass_b]

3 point contact, yes, a couple tenths, lots of it.

[craiger_ny]

How far off are your readings? I assume you checked for shanking out and a loose styli. Bear with us, this can be a long process. 3 point contact gage will not give you a good representation of roundness, you might want to see what PCDMIS says about roundeness not only of the cylinder but of individual circles.

[#2#]

Are you measuring them with 2 levels? Sometimes with only 2 levels it calculates a cylinder's vector at 90º to where should be. That usually doesn't happen with that many hits but...

Location? Did the cylinder's location change causing your hit vectors to not be normal to the surface?

Recalibrated at start cleaned probe. Using least squares, constucting cylinder. 32 hits total .001 tolerance.

Are you measuring two circles with 16 hits each and then constructing the cylinder? If that is the case, dimension the diameters of both circles and see if they are similar to the diameter of the constructed cylinder.

[Don Henger]

What are you verifying them with? 2 point contact bore gage? 3 point contact? Are they round? Are they tapered? Do you drink beer? Have you evaluated the individual circles for roundness and size? Are there any surface annomolies (what is the finish like)? What are you wearing right now?

3 point contact, yes, a couple tenths, lots of it.

O.K. you have answered the first three questions. (good answer to the beer Q).
I would do what craiger said to try to find the individual circle where the cause of the variance is in the cylinder. What is the micro like? How much of a differance are you talking about from yesterday to today? Also most important to Craiger to keep him interested in this thread is What are you wearing right NOW???

[kass_b]

Problem solved must of been shanking out on deeper circle, went back re aligned to machine axis within .001 now all is fine. Didn't have enough beer last night. Old lady yacking to much on the way in. THANKS