Harbor Freight electronic calipers warning

WOW, an ON topic post! My 12" Mitutoyo calipers turn off after about 15 minutes and then I need to re-zero.

These are 20 year old digital calipers so the newer ones could very well be different.

Seen Precision Machinist lately Charlie?

Best, Steve

reference? I was

No, and I feel bad about not being able to find time to ride down his way this last summer. Being an Area Director for a motorcycle club really eats up my free time. I may have to sit down and look at a calendar to see when I can have a weekend free next July or August. With any luck he will come up to the city on his birthday and actually want to talk to me.

Thanks Don - I'll keep that in mind.

Hul

Winston - good point. The 8 in. caliper was losing the reference in an easily replicated way. The 12 in. devices wouldn't loose a digit in my living room. In the shop with, a dc motor running, they certainly would. I'll try to verify the motor being the cause tomorrow.

Hul

Oh! I've got a Starrett 150mm one -- from back when the bezel around the crystal was metal instead of black plastic.

And given that it is a dial caliper -- the question should have been "how does it feel?" The Starrett (metric) dial caliper feels a lot smoother than the Phase-II (inch) dial caliper, but both work well enough.

And, I've recently had occasion to use the 24" Scherr-Tumico vernier caliper which I picked up at a hamfest this last summer. It is the style with inside measurement jaws ground on the outside of the outside jaws, and you flip it over for a second scale and vernier to read from the inside measurement jaws. I wasn't sure that I would need it, but it was in very nice condition, and in a nicely fitted wooden case. (And, the vernier scale is stretched out more than the usual ones, making it easier to read with old eyes. :-)

Enjoy, DoN.

Yes -- but that gets expensive -- buying four of the adaptors per caliper. The prices are not too bad for photographic equipment.

I've verified that it will run from 6.000 V, instead of the

5.400V from four mercury cells in series. But the problem with the silver oxide cells is the shape. The PX-13 (or was it the PX-625?) has a shape sort of like this (view with a fixed pitch font like Courier to avoid the distortion which would come from a variable pitch font as is common in todays programs which act as newsreaders): (-) ________ /________\ (_.........._) |________|

(+)

And the cell holder for the caliper really *depends* on that shape to make connections between the cells, and to force the proper ones to be + side up.

So -- I plan to modify the cell holder (or make a new one if necessary) to accept two 2032 cells instead (provides enough voltage, and a lot easier to find). And -- with a switch, I should not have to replace them as often -- unlike the Starrett, it is not easy to pop the battery pack off when you put it away.

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Yes, I am afraid that you are right. The only caliper which I have bought new (other than the 12" Mitutoyo) is the nameless one from a hamfest about three years ago. To identify it, the only text on the beam (other than coarse printed inch and mm scales) is the words "Electronic Digital Caliper", but on the back of the carriage are two tables -- giving dimensions for metric/iso screws (3 mm to 20 mm), and Whitworth screws (1/4" to 1") -- a strange set of tables for a caliper sold in the USA, but I find it convenient to have both available. Oh yes, it also has the CE certification symbol on the same label with the thread tables.

Enjoy, DoN.