DIY Like a Pro: How to Pick a Good Caliper for Precise Measurements

[Adam Funk]

I've had a digital caliper from Aldi for a while but it now randomly adds multiples of 5 mm to measurements, even though I've changed the battery. I had a quick look at the Screwfix and Toolstation websites and I was pleasantly surprised at the prices (I assumed calipers would be more expensive) but I don't know the brands.

Magnusson Digital £21

Magnusson Vernier £14 Minotaur Digital £21 Minotaur Manual [Vernier] £14 Are these any good?

Obviously digital is more convenient to use, but potentially less reliable in the long term. Comments?

Thanks

[Harry Bloomfield Esq]

I have a couple from Lidl/Aldi, and never had such a problem. I think I paid around £6 for the first one and both seem to be very accurate.

I think you will find they all originate from the same factories in China, so nowt to choose between them.

[alan_m]

BigClive video

[Theo]

I bought some 4 pound plastic ones from ebay. They work, the distances are ok, but:

- They don't properly go to sleep so the batteries run flat in a short while (even in the packaging). Apparently there's a way to force them to 'hard off', but easiest is to just pull the battery.

- The battery cover doesn't fit very well.

- They had a habit of getting a random offset on them. You can zero this out, but occasionally the offset would appear mid measurement. Being a plastic body it's possible it was caused by bending it in a particular way.

- Accuracy in real life could vary a bit depending on how the slider was moved.

I got what I paid for, but not a lot more. I go to the vernier set every time. I would not expect the plastic ones to last long term.

Some of those seem outwardly similar to the ebay ones:

although they might be plastic jaws - I think the body has to be plastic for the capacitive PCB track to work. Hopefully the Screwstation ones are better build quality than the ebay version?

I've currently in the market for some angle measurers:

wondering whether they'll be as flaky as the cheap calipers.

Theo

[alan_m]

Even he £100 versions take 1uA when in the off state. I watched a Youtube video comparing a real £100 unit with a fake Ebay version of a top end unit (selling at £50) and the fake took 20x more current in the off position.

My £20 no-name unit with metal jaws and slider will run down the battery if unused in the case for around 6 months. I just keep a couple of spare batteries in the case.

Again watching a Youtube video the same can be said for the cheapest (£10) to a more expensive unit (£100). All were accurate to within 1 thousand of an inch and all could be changed by around +/- 1 thou by applying more/less pressure to the slider wheel.

[Fredxx]

I've seen the same issue, but instead it's been 5.08mm which of course is 0.2"

[Andy Burns]

A decent proportion of the ones claimimg to be Mitutoyos are fake, better qusality perhaps than the cheapos, but not necessarily more accurate, but the "absolute zero" position is rememered.

search for clough42

[Adam Funk]

You're right, it's 5.08 rather than exactly 5 mm.

[Brian Gaff]

Its the encoders that are the problem. These often work basically with an optical sensor attached to one end and the other end with the light, and the static bit tends to get loose. Some used to use strain gauges, but I remember one of those going weird when I worked at Racal all those years ago. I guess nothing lasts for ever. It also depends on how much you abuse these devices. For some reason some people have bad luck with this sort of thing and others do not. Is this Murphy or sods law? Luckily, unless somebody makes a talking one, I have little use for such things these days. Brian

[Andy Burns]

I think they use thin stripy capacitive tracks on two circuit boards, which slide past each other.

[whisky-dave]

Don;t know about those bet we've just bought some of these.

Seems pretty good so far for the £7.50, nice big display . cheap enough to hand to students and they should be capable of using :-)

Biut not used them much so relibaiulty not know as yet.

The hazadous reference is because of the 2032 battery I assume.

Another item I've found to be good value while ordering is a 10X loupe for £1.84

[Rod Speed]

Brian Gaff [e-mail] wrote

That's less clear.

Hasnt been like that for a long time now with the diy class stuff.

Never seen that 5mm jump at all. Bet that's a design quirk likely in the chip used.

So how do you measure stuff now ?

[pinnerite]

I have a beauty: Powerfix Profi purchased from Lidl. I think it was £9.95 but certainly under £15. The manufacturer is OWIM Gmbh & Co. KG, Germany. The model Number is HG00962A

[Adam Funk]

The current batch is £10 each in Aldi now.

You think the £20-ish ones are the same as the Aldi ones with fancier labels?

[Adam Funk]

I came across it after watching the Big Clive video that someone else linked:

[Adam Funk]

Interesting, thanks.

[Adam Funk]

I think I'll just get a (non-electronic) Vernier item: slightly more effort to read but much less to go wrong.

[wasbit]

In that case go for dial calipers.

[Adam Funk]

What's the advantage?

[wasbit]

Clarity.