Holtests, Hole micrometers???

[groovemixer]

I'm looking at getting holtests for holes of .240" up to 1" ID, measure to +/- 0.0002". Was wondering if Brown and Sharpe are a good brand, I usually buy Mitutoyo. Also are the small hole guages good enough? The ones that are set to the hole size then measured with a micrometer.

[jackson]

Originally Posted by groovemixer I'm looking at getting holtests for holes of .240" up to 1" ID, measure to +/- 0.0002". Was wondering if Brown and Sharpe are a good brand, I usually buy Mitutoyo. Also are the small hole guages good enough? The ones that are set to the hole size then measured with a micrometer.

B&S is good but i stay with mit. and starret just a prefrenss i say stay with what your use to and trust and yes the gauges are good enough.

[RICHARD ZASTROW]

The telescoping gauges can be ok in experienced hands. The cheap telescoping gauges being sold lately are not dependable, they bind up and stick. Measuring +/-.0002" reliably is difficult enough without trying to do it with junk.

[BobWarfield]

How about a bore gage? Mitutoyos were on sale recently at Enco, I think.

Best,

BW

[ajl6549]

Originally Posted by BobWarfield How about a bore gage? Mitutoyos were on sale recently at Enco, I think. Best, BW

Originally Posted by RICHARD ZASTROW The telescoping gauges can be ok in experienced hands. The cheap telescoping gauges being sold lately are not dependable, they bind up and stick. Measuring +/-.0002" reliably is difficult enough without trying to do it with junk.

I agree if your not experienced with telescoping gages try dial bore gages.

[jackson]

Your best bet is to use tri mics if you have to hold a tite toleranc

[BobWarfield]

Originally Posted by jackson Your best bet is to use tri mics if you have to hold a tite toleranc

That seems not to be totally the conventional wisdom. For example, the trimics can't measure certain kinds of irregularities with 3 points that you can find with 2. I started out on the trail of trimics and had a bunch of people over on the PM boards push back in favor of bore gages. It's worth searching over there to see if you agree with their thinking.

Best,

BW

[Zumba]

I've got the Mitutoyo bore gages from 0.7 to 6.0 (three sets).

The smaller ones are freaking expensive. Much better than telescoping gages though. You won't be able to get .0002" accuracy with those.

[jackson]

Originally Posted by BobWarfield That seems not to be totally the conventional wisdom. For example, the trimics can't measure certain kinds of irregularities with 3 points that you can find with 2. I started out on the trail of trimics and had a bunch of people over on the PM boards push back in favor of bore gages. It's worth searching over there to see if you agree with their thinking. Best, BW

Well i have used both and both have there place i have found that the tri takes a more true reading "yes i know it takes an avrege by three or what ever" but of all the places i have done work for i have never had a part rejected when using tri mic, bore gages "i still use them" but i have been bit more by them than any tri mic!!! just my opinion and what i know

[Newby2]

For a .0002" tolerance a tri mic or bore gage is the only way to go. telescopes are outdated and inaccurate. They may get you to within .003" if you are experenced. With a tri mic, you should have a certified master that came with the mic. If you don't have the master, then I would doubt the accuracy you are trying to hold.
Steve