Originally published at: https://boingboing.net/2017/12/07/these-digital-calipers-are-on.html
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If you need calipers, I’d suggest spending $5 more to get the ones with stainless steel jaws and frame. There’s too much deformation in the plastic ones, “carbon fiber” or not, to be useful for much precision work. The accuracy of the metal ones isn’t too bad, though not nearly as tight or durable as a nice Mitutoyo set.
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I don’t know about these particular ones, but I found that cheap calipers in general eat batteries like crazy:
It’s very annoying to take them out and discover the battery is spent.
I couldn’t justify Mitutoyo prices for my uses, ended up with buying iGaging brand:
They were like $30 from Ebay and good quality.
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Or $5 less from China (free shipping) if you don’t mind waiting for the slow boat from China.
I think these are basically all the same tool. I bought one exactly like @asdasdetc’s video, but a different brand. Price was comparable–around $30. They’re fine for my needs, but if I was doing work that had very fine tolerances, I would probably not be as pleased.
The thing about digital calipers is - when you really need them, the battery is dead.
And learning how to read a vernier scale isn’t rocket surgery.
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I think you can do alright with this sort of middle-low range type of thing if you’re not in critical need of very close tolerances. The $10 ones are just garbage, and will lead to tears in short order. I question whether anyone willing to put up with iffy devices that purport to scale to the .0001 in. really needs something like this. A compass or plain calipers that you then measure with a ruler is probably the ticket for ‘close enough’ applications, and then you don’t have to mess with batteries and another cheaptastic tool taking up space in your toolbox.
Must you recommend such crap? You either need a precision tool or you don’t. These things are just abominable garbage, and should not be promoted or relied on.
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My Mitutoyo Vernier caliper calipers pair of calipers instrument cost, I think, around 30 pre-Brexit UK pounds, and that’s as nice a tool as you can get, and makes you feel like you’re an engineer in a luxury car commercial. Unless you’re buying 100 for a prison workshop or something, I think it’s silly to try to save like $10 on something that would otherwise last a lifetime and be actually pleasurable just to hold.
That sounds pretentious, but (a) I think you are pragmatically more likely to leave a cheap-feeling tool on a garage floor and end up running over it, and (b) what, you’re measuring stuff to the nearest tenth of a millimeter on the reg, but you don’t care about details?
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To all those complaining about batteries: in things like digital calipers where most require greater than 1.3V to run, you should use silver batteries rather than alkaline. For reference alkaline coin cells have an “L” as the first character of their “size”/type while silver is “S”.
The voltage in alkaline batteries decreases as they are used and while they have a nominal voltage of 1.5V, by the time they are only half used their voltage has dropped below 1.3V. The voltage curve in silver batteries is rather flat. In addition silver batteries generally have higher capacities for the size. They’re slightly more expensive than alkaline cells but they’re extremely worth it for the application.
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Huh, I’d never heard of silver batteries. Though I should say, it’s not battery life that puts me off digital readouts – I assume it’s no more of a hassle than it is for watches and calculators, i.e. none at all – it’s just that an LCD display detracts from that feeling of pretentious haute qualité.
That, and the extra precision is mostly spurious, in the sense that you’re usually taking a single measurement from a 3D object, and most objects aren’t regular enough to justify measurements to the nearest micron.
Damn!! I was hoping for a cheap calliope…
You can get similar precision with vernier calipers or dial calipers but things are just so much faster with the digital calipers even when you don’t care about precision beyond a millimeter or a tenth of an inch. Being able to see a digital readout is much quicker than looking at a row of lines even when I was young enough that I didn’t need reading glasses to see them. But I also do care about being able to measure things to a couple tenths of a mm regularly and on rare occasions I need better precision than that. So having good calipers is worth my while. A fraction of a mm is the difference between a lid fitting loosely or not at all and when you want a tight fit you need decent precision.
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Sure, I mean, my calipers are marked in 0.05mm intervals, and I often use that much precision for CNC-related stuff, but some of the digital ones appear to show millimeters to three decimal places, which seems optimistic, even if you trust the calipers themselves.
I will admit that eye strain is a consideration, although the nicer Vernier scales are WAY better in that regard. That was actually what drove me to spend the £30 in the first place.
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I know, I know… but they still manage to die on me at the least convenient moment.
Also, no matter where I work, I’m the one who refills the paper in printers and copy machines.
On the other hand, I’m nearly always lucky when I need a parking space.
Swings and roundabouts.
We use these at work, and I will attest they hold up well. We don’t treat them all that kindly, yet they stay accurate day in and day out.
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From what I understand, the power button on the cheap models doesn’t actually turn off the whole circuit, just the display.
Agree! Really prefer mechanical to digital. The idea of running out of power at an inconvenient time just grates on me, and it can be less obvious if electronic components aren’t doing exactly what they’re supposed to do.
I found possibly the same model on Amazon, and have found it invaluable for design classes the last couple years:
https://www.amazon.com/gp/product/B00B5XJW7I/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
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Agreed. A dial caliper is a fine alternative to most.
If you use metric measurements, you should make sure you buy a dial caliper with 0.1mm scale. Many have 0.2mm scale (one full rotation is 2mm) which is kind of annoying to read and (for me) unnecessarily increases the risk of a mistake. Also making comparative measurements is a little more annoying since you have to 1) loosen the screw 2) rotate the bezel to zero 3) tighten the screw again. Instead of pushing a button.
