Three recently bought electronic calipers from Harbor Freight turn themselves off after a few minutes of inactivity. Some turn on again if moved (12 in version), the others (8 in version) need be manually restarted. The 8 in. one shows zero when turned on & the 12 in restarts with some of the same numbers but not all. bleep, bleep, bleep. Anyone zeroing calipers on a reference and expecting that to hold longer than a minute or two need find a source other than Harbor Freight. Any suggestions on electronic calipers that hold their reference? I was thinking of trying Enco's versions. If anyone here has one that works, please mention it.
Mitutoyo Absolute digimatic is the winner! Mine is _never_ turned off and the battery lasts a very long time. Silver oxide 347. Several years ago I bought a pack of three and I still have one left. My mill has a Mitutoyo DRO made in 1980 and it too has never been turned off. Good stuff........ You are wasting your time and money with junk cheapies from HF.
I generally prefer Starret. Yeah probably not the best value, you're mostly paying for the name. But I like the feel & that they're made in the USA, to me the premium is worth it.
The last time I was in the market for a 6" caliper J&L happened to have them for ~$10 or $15 less than most anywhere else. The model # was slightly different, but what the hell, a Starret's a Starret, right? Wrong, this one's made in China (model #1202A-6)! I should've sent it back, it pisses me off every time I pick it up.
While I'd certainly invest more in "name brand" if it were for business use, my HF calipers (6" and 12" varieties) purchased a few years ago have not given me any usability issues. They do tend to eat batteries, but for a home shop it's no big deal to pop the battery out when you're done using them.
Well ... if you are willing to put in serious money, some Mitutoyo ones will not only hold the reference, but also can hold both a temporary reference, and hold the absolute zero, and switch between them by holding a button a few seconds.
Well ... I have a Starrett, a Mitutoyo Digimatic, a no-name import (cheap from a hamfest), and a couple of B&S (really made by Tesa, I think) which need cells which are no longer available -- the mercury based PX-625 IIRC -- or is that PX-13? I would have to go down and look to be sure. Anyway I have verified that I could run them off two 2032 cells if I modified the battery holder, and will probably do that sometime. (Oh yes -- this is just the 6" digital calipers. I also have a 12" Mitutoyo which is a beautiful tool.
Anyway -- of those, the Starrett, left to its own devices, burns out two 2032 cells faster than the Mitutoyo does one SR-357. I simply opt to live without the memory for zero and push on the holder for the cells to slide it far enough to disconnect whenever I put them away. Doing that, I get very nice battery life.
I also have had two Starrett 0-1" digital micrometers fail, so I've written off their digital instruments. When the Starrett digital caliper finally dies, I will probably get another Mitutoyo. (I keep one near the big lathe, and another near the little CNC lathe.
Of what I have, the nicest is the Mitutoyo Digimatic, with two memories (absolute zero, and convenience reference zero) which carry though turning it off and storing it.
If I ever get around to modifying the battery case for the B&S/Tesa, I will probably add a convenient switch, because those really eat batteries. :-)
Does it work? What kind of battery life do you get from it?
A lot of photographic lightmeters used the mercury PX625 button cells. When mercury went away, the fix was to go to a silver oxide cell with a germanium or schottky diode in series, to drop the voltage back into the correct range.
Now, I bet that a caliper will work just fine if driven by a silver oxide cell, even if the voltage is slightly high.
Starrett seems to have been hollowed out. I love their old stuff, buy it used and clean it up. I regularly use micrometers that have to be 90 years old, and work perfectly.
But their new electronic stuff isn't competitive, and I don't know why they cannot solve the problem. I have Mitutoyo and HF digital calipers.