Test Indicator & Dial Indicator Calibrator
Although indicators can be calibrated quite accurately using nothing but an indicator stand and a couple of gage blocks, if you have many of these to do, you'll save a great deal of time and frustration by investing in the UDT-2 dial gage tester made by Mitutoyo.
Although designed for use with Mitutoyo indicators, this calibration apparatus will work with any other brand of indicator. The indicator is mounted using the stem or the dovetail as the situation warrants.
In effect, it's nothing more than a sturdy stand with an oversized micrometer head and a bunch of fixtures to hold your indicators.
You will be limited to a 1" range so you'll still have to use gage blocks for any long range indicators you might have. Furthermore—and quite significantly—this kind of mechanical calibrator has .0001" graduations and only has an accuracy of ▒.0001" (or ▒ 1Ám in the metric version). This means you will be limited to the calibration of .001" and .0005" indicators. "Tenths" indicators will require a careful gage block set-up or electronic calibration. But, that's another story.
You will also be limited to either inch or metric. If you use both systems, then you would have to buy two separate calibrators.
Bore gages can also be calibrated (keeping the accuracy limitations in mind) if you purchase the optional gage stand adapter. This adapter is specifically made for Mitutoyo bore gages however, and may not work with other brands.
These items are rarely in stock. You will want to allow up to 4 months for delivery.
Q: My bore gage range is larger than 1". Will I be able to use this calibrator?
A: It may have an overall measuring range that's longer, but the actual travel on the indicator is much less than an inch. If it's a Mitutoyo bore gage with .001" or .0005" discrimination you'll be all set.
Q: Won't my indicator calibrator eventually need to be calibrated as well?
A: Absolutely! You decide on a time table based on the amount of use—or abuse—that that calibrator is subject to. You'll have to use calibrated gage blocks along with some ingenuity, or send the whole thing to a gage lab that can deal with it. From experience: if you send it out, package it very carefully. The last thing you want is some damage in transit. Also, keep in mind that you'll be without the calibrator for several weeks and plan ahead.