I would love some solar powered calipers. "I'll wing it" measurements for me are usually powered by "god damn it, do I even have any more CR2032's? Is the battery cover pressing down enough? Screw it where's a ruler..."
Get a Mitutoyo, it'll be accurate AND the battery will last 5 years. It only hurts once. Cheap calipers hurt every time you use them :/
Recommend you take the CR2032 out when not using the calipers. Cheap/no name ones (atleast those sold 5-10 years ago) have a relatively high standby current, even when the LCD screen is off.
I just flip the coin cell around so it stays in the device but does not deplete (reverse polarity but in fact the contacts will not touch the battery poles so no harm).
Would you happen to know the current draws for the older and newer designs? I would like to check if mine are worth replacing (since I dutifully remove and store the battery in the designated holder in the case I can't rely on durability comparisons because it would depend on usage patterns).
I don't know the current draw of either. I don't know if newer designs are better, I only have one I bought around 10-15 years ago. For mine a bettery left in the calipers depletes within a few months, without use.
Even my cheap 100% plastic calipers have been running for 2years. And yes they cost $100 but my good calipers have been running for 5years or so
It would be super cool to do some sort of energy harvesting when you move the calipers open and closed.
Solar calipers are around US$10 at the usual far-East online shops.