Telescoping depth gages? What does a Home Shop Machinist need?

HMF

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Hey Nelson,

Those Starretts are nice. I use a lowly import set I bought from Amazon. They work well but I only use them for diamaters less than 2.1" - above that I have a dial bore gauge set I bought for engine builds for my Camaro. The dial gauge is easy and fast to use as you can readily find the "perpendicular to the tangent".

By they way, these are bore gauges not depth gauges.

John
 
I prefer the 1st type snap gauges. The Starrett 579 Set will telescope from both ends, allowing more room to swing the handle in a tight or irregular shaped place. Some places can really get tedious.

Some Starret snap gauges only telescope on 1 end...look closely at the pictures. If you have to swing the handle on center of a bore, it can be next to impossible.

BTW, most import gauges telescope (or supposed to) on either or both ends. Most are not as smooth as a Starrett though. This could introduce error if they are sticky or feel detented.

The single advantage that the imports have on the Starrets is that when you have to measure between two flat surfaces (like a large keyway) you can lay them flat on their side... their center section is square. The center section of the Starret is round, making this a tad more hit and miss in some applications.

Good luck.

Nivlek
 
Nelson,
I have several sets and I seldom use them. It is amazing what a home machinist can do with a good dial caliper. :D
 
I have Starrett, old Craftsman, and Mitutoyo. I actually prefer the Mitutoyo set. Longer handles, smooth action. I regularly use them to a few tenths tolerance with no problem. I can double check myself with my TesaHite, and can't complain.

I agree, a must have for close work. By that I mean +/- 0.0020 or less. For one or two pieces, it's not worth setting up a bore gage, unless roundness is also critical. Other issues come into play then. Calipers can't reach the depths that telescoping gages go. Firm joint, and spring calipers can, though. :)
 
the first 3 small sizes on a six gauge set they also make a 5 gauge set but only if you have a inside mic set. if not then a full set is useful bill excue me I thought you were talking about standard telescope gauges not depth gauges
 
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I have a set of Starrett telescoping gauges that I use once in a while for hole diameters. Most of the time I just use my dial caliper unless I need better accuracy. The key thing with telescopic gauges is that they are only as good as the person using them combined with the micrometer you use to measure the resulting dimension of the gauge. It takes a little practice to get good consistent readings with telescopic gauges. Even inexpensive telescopic gauges will usually do a fine job as long as the lock mechanism does not tend to move the telescoping ends as the lock is tightened down.

For hole depth measurements I either use a dial caliper, or, if I need a more accurate measurement, I use my Scherr-Tumico depth micrometer.

For measuring the distance of the edge of a hole from the edge of a part, I use my Starrett pin micrometer, or multi-anvil mike as some guys call them.

As for which one you purchase, the Starretts are good, so are the Mitutoyos and the other well known brands. Surprisingly, even the imports are generally pretty good for the most part. Biggest thing to remember is that they can be damaged easily to where they no longer slide smoothly, regardless of what brand you purchase. Purchase with caution when buying used. Myself, I did not even look at used ones when I bought mine, but that was long ago in a galaxy far away...

ON EDIT: I just realized that this is an old, old thread. Oh well, it will be good information for some of the newer folks.
 
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