Generally, you think that if you pay more for something, it must be better, right? But that’s not always true. Even if it is true at the lower end, sometimes premium brands are just barely better than the midrange. [Project Farm] looks at a bunch of different calipers — a constant fixture around the shop if you do any machining, 3D printing, or PCB layout. The price range spans from less than $10 for some Harbor Freight specials to brands like Mitutoyo, which cost well over $100. Where’s the sweet spot? See the video below to find out.
The first part of the video covers how much the units weigh, how smooth the action is, and how much force it takes to push it down. However, those are not what you probably care most about. The real questions are how accurate and repeatable they are.
If you just want a summary of the first part of the video, skip to the ten minute mark. The table there shows that the three instruments that have the most consistent force on the slide range in price from $27 to $72. The $454 pair (which, to be fair, included a micrometer) was number six by that measure. The smoothness factor, which is somewhat subjective, came in favor of the most expensive pair, but there was a $25 caliper that was nearly as good in the number two slot.
Using a calibration block and some special techniques, he attempts to see how accurate they all are. We wish he’d used millimeters instead of inches, but in the inch range, none of them are bad. Only one set had a real problem of not making consistent readings.
If you want to jump right to the tables again, jump to the 17:20 mark. With two exceptions, they were all mostly accurate and fell into three groups. We wondered if there are three different chipsets involved. The cheapest caliper in the first group cost $27 and was as good as the expensive Mitutoyo. The second group ranged from $18 to as much as $40 and were only 0.000675 inches (only 0.017145 mm) off from the higher group.
Which was the best? That table is at about the 18:00 minute mark. In all fairness, the best, by his estimation, did cost $144, so it was the second most expensive set in the review. But that’s still cheaper than the Mitutoyo, which placed third. The fourth-place set was good, too, and came in at $27. For a few bucks less, the sixth-place caliper was also good.
Do you know how to do all the measurements your calipers are capable of? Ever wonder what’s inside those things? We did too.
“Generally, you think that if you pay more for something, it must be better, right?”
Wrong. If you must pay more for something it means 1 thing, and 1 thing only. The company wants to charge more for their product. We’ve lived our entire lives with mega corporations being able to ignore micro-economic factors like customer satisfaction for economies of scale, monopolistic practices, market protectionism, government subsidy, political corruption and promo manipulation to think that way.
It always takes comparative testing, communication, and diligence to get to the better products. Can they be better? sure. But thats essentially coincidence.
I try to tell this to people all the time, with my heavy use of aliexpress id never go back, the amount of people i have blown away with my $20 Chinese IEM earphones while they use $400 airpods.
The problem is my $20 ali IEM earphones were utter crap.
You got lucky and got the good pair. But it’s a crapshoot.
I could have gambled I’d get a good pair next time, but I’d soon have spent more than the $150 I paid for my AirPods, which inevitably just worked.
Sure Dan, but the satisfaction of getting a dirt cheap thing that is great is unmatched though.
It’s such a nice experience.
I suppose that is sort of what the gambling industry also uses, people lose and lose and lose, but the win is so sweet. But like you, a smart person knows you can’t force it and you should not gamble like an idiot for a one time thrill.
Sometimes though there is stuff from ali that is consistently good and cheap and it’s not much of a gamble.
And we are back to the value of comparative reviews to sort the actual wheat from the chaf. In the case of IEMs, the guy at https://www.scarbir.com/ has been reviewing these things at a range of price points for years now. The couple of times I’ve needed to buy IEMs his reviews have been on point.
Markup is a thing on many commercial products (esp. luxury brands) but it’s also true that many things simply cannot be made in decent quality for cheap.
Bearings for example – yes you can buy bearings for dirt cheap but to really make a good quality one that lasts for years requires precision, high quality materials, finishes, and treatments as well as quality control all of which costs money.
The industrial market is competitive, there are trade counters and online stores devoted entirely to selling bearings & seals who compete with each other. If they all quote me ~$50 for a real Timken or SKF bearing that I can buy on Aliexpress for $5, although I know there’s a markup in there (everyone has to keep the lights on) I also know there’s a much better chance that bearing is going to last for the next decade.
The last calipers I bought on AliExpress were £1.40 a set. Yes, digital calipers. £1.40.
I really like project farm, and support him on patreon, but I think he missed the mark with this video. Yes a cheap pair of calipers can be fairly accurate and feel smooth. But this is a tool that an engineer or machinist often uses every, single, day. All the time. $250 is really not much to pay for a solid tool that’s trusworthy, reliable, and lasts for decades of heavy use. I have a pair of Mitutoyo calipers on my desk that I bought back in 2007 USED. I’ve been using them all through college, and for my entire career since then. 18 years of daily usage and they’re STILL working perfectly.
I’ve owned several other pairs of calipers, and they have been accurate enough, but the plastic and metal parts are lower quality and they often break. They also eat batteries. I have a cheaper larger pair, and the batteries are always dying. Extremely annoying. When someone I work with has a cheap pair and I try to use them, they’re invariably dead. Or you have to push the battery cover on just right to get them powered, the slightest jiggle turns them back off.
So my advice is this, if you’re working with mechanical things often, buy the Mitutoyos. It’s a BIFL purchase and you will not regret it. If you only need calipers once in a blue moon. Buy some cheap set with a good rating on amazon, then take the battery out when you’re not using them. Also store them in the case. If you do that, they should be ready to use if you need them.
I would argue that the occasional/light hobbyist user would be better served with a Vernier caliper than a digital one – there’s no electronics to break and no battery to go flat. I’m very happy with mine, which was quite cheap but not as cheap as the absolute cheapest digital calipers
I only buy regular verniers, they’re not hard to read, they are never out of battery, and they don’t care about contamination.
Also worth saying Mitutoyo do some cheaper (<$50) callipers that are great – 530-122 lives in my desk drawer, resolution 0.02mm and has an RRP of 46 euros.
I agree. The first digital one I saw up close was one a QC man in the company was using, and when things didn’t seem right, I measured it against a known standard, and the digital one had gotten way, way off, even visibly so. Since then, I have not been able to trust digital ones. I only use the mechanical ones.
Yeah, stuff like that is very annoying, and is my experience too. I got two Mitutoyos at home, literally looking at one as I write this, but I also have two verniers, and two cheaper digitals where one is completely plastic to measure across batteries and electrical stuff. I’ve modified the other not that cheap digital by adding a tiny on-off switch, since it ate batteries, and it sometimes makes insane faulty measurement jumps, hence I bought a second Mitutoyo. I’ve never had any issue with my two Mitutoyos, or the one I have at work, and I two of those are more than 20 years old. And I do have a few calibration blocks I can check with to make sure they measure right.
Other types and brands of calipers have their use, especially if you hardly ever need to use one, and then I recommend a vernier, but if you use it every day or just a lot occasionally and want something good that last and can be trusted to work and measure correctly? Get a Mitutoyo.
I’m probably part of a small group who carries a vernier caliper not just in my car or when travelling, but also when hiking in remote places like out on Hardangervidda or Jotunheim in Norway. Being alone on a hike makes me think and come up with ideas.
The thickness of a leaf.
I have a pair of Mitutoyo calipers that I inherited from my dad, which he in turn ‘inherited’ from Philips in 1982. :) It’s a vernier caliper, so never needs calibration or batteries. Its precision is 0.1mm. And if I use my reading glasses or a magnifier, I might be able to get to 0.05mm precision. It’s always ready when I need it. And it didn’t cost me a thing. Also, I’m very careful with it, because it’s just such high quality.
I have another cheap digital pair of calipers. But to be honest, I have no clue where I put it. Because the battery runs out once in a while, and I have to go on a battery hunt, breaking my focus. The Mitutoyo simply never lets me down.
But also do note that I’m not a machinist and that I really never need 0.05mm precision. :) What I want is something that does not let me down the moment that I need it.
I also use the Mitutoyo to judge the precision of my other measuring devices.
But to be honest, I should buy some calibration blocks. Exact length measurements are hardly ever necessary, as I mostly measure something and then copy it. If you don’t switch measuring instruments, you’re always going to be good.
But if you use CAD, it often does become important to know that 100 CAD mm is exactly the 100mm in real life, and not e.g. 99.6mm.
If you need 0.05mm precision, you definitely are not using any calipers.
‘jus sayin’
That’s .002″. Not a problem with my mechanical dial caliper.
Yeah, longevity and long-term reliability is a thing I am happy to pay for.
I have a set of coolant resistant IP rated Mitutoyos that I’ve had for nearly 20 years. They haven’t had an easy life but they are still in great condition.
I wonder how accuracy is affected across temperature range between cheap and expensive calipers, and how is the hardness of the jaws and wear surfaces etc on cheaper calipers?
The battery problem is the reason they ship with one or two spares, which is no enough. All the cheap ones have the same chip-on-board (Is that the right term? Chip under a blob of epoxy.) and consume batteries very quickly. And whatever the OFF mode is, it isn’t off. They use that little battery because the original reference circuit uses it and so do the units they are copying.
I bought a case of the $10 type once in Shenzhen to use as a give-away. When they died within a week or two we got a bunch of new batteries and – yup – battery eater. I have a very nice Craftsman I bought around 1986 for $90 ($264 today!) that needs a battery every 10 years or so. Maybe longer. It is smooth as silk with just the right amount of friction.
Usually the watch battery size. Those just don’t seem to last long, regardless of the device. Now the 2032 coin size can last years. They rarely leak too.
This solved the battery problem and works like a charm:
https://www.printables.com/model/566515-simplest-aaa-battery-holder-for-your-caliper
Great idea! You can also get 2/3AAA and maybe shorter.
Mitutoyos are fine, if you can’t afford a decent SPI…
Joking…
Swiss products are all basically Rolex.
Status symbols.
Calipers that can get you laid…
Also.
Verniers are the way to go.
Any pricepoint.
KISS
At some price point the swiss caliper dials have to approach Rolex dials, diamonds on the #s.
Useless complications.
” They also eat batteries”-absolutely this. I have worked with the Mitutoyo calipers since the 1990s, including measuring sample swelling in water (never a spot of rust, despite never doing anything other than wiping them dry). The batteries last months, where the $20 caliper I bought at Cabelas eats those stupid little silver watch batteries like candy. Put that caliper away for a couple weeks, and the battery is dead. Not to mention the Mitutoyo shuts itself off automatically., where the cheap ones don’t.
The one I really liked, with solar cell, I haven’t been able to find for my own personal purchase.
It took me a while to realise that the reason the case my (cheap) calipers came in has a spot for a battery, isn’t because it’s for a spare battery. It’s so you can take out the battery every time you put it away.
I only use them every few months, so popping the battery back in isn’t much of a bother. I’d get a vernier caliper, except I already have digital calipers, and I’d have to find my glasses every time I wanted to use them.
oh yeah. The Mitutoyo were expensive AF but they work every time. I got tired of the cheapo calipers draining battery, losing zero while sitting in the box, or disconnecting in-use because the battery door sucked.
The metric I missed was how long they’ll last on a battery when not used. That varies a lot.
Two other metrics I missed are:
What happens when a 80kg person stands on it multiple times?
What happens when you drop it from a height of 1.5 meter multiple times?
Maybe even a third metric:
What happens when you throw it across the shop multiple times?
But maybe most other people vent their frustration in a more constrained way. :)
I would wager that these are going to be Amazon returns, so you don’t want to use them too much.
You forgot – how long do they last drenched in cutting fluid?
i think i’ve changed the battery in my mitutoyo once in the last 6-7 years of ownership. (i’m probably not a heavy user.) my no-name chinesium digital calipers produce the exact same measurements, but if i leave a battery in them, they’ll be dead in a day or two.
switching gears:
my concern with the cheaper models would be poor QC. i expect every mitutoyo meets the specs here, so you can just get one and use it. i’d be concerned that the $20 ones will have a 1-in-100 unit that’s wrong enough to cause problems, but but not so wrong that you notice unless you do comparisons.
i don’t understand how the mitutoyo is being listed as $454. even with data output and calibration certificate, that isn’t what mcmaster charges for the 150mm digitals.
“We wish he’d used millimeters instead of inches, but in the inch range, none of them are bad.”
I never realised that precision is relative, depending on if you use mm or inches. I guess inch-people care less about precision than mm people?
;)
That’s resolution, not precision.
Inch-people don’t care about much — and this coming from someone located in the larger of the two countries left unmetricated.
I mean, seriously, us and Myanmar???
In the mid-1980’s I worked in a company’s lab that had a machine shop across the hall that I had to go into frequently. They used inches exclusively.
I got relatively decent steel calipers. But I love those cheap plastic digital ones. They don’t become magnetic. It’s such a huge pain to clean my calipers every time I wish to use them, otherwise my measurements are completely off. I buy those cheap ones several at a time on a chinese site and they work fine for a few months. And when it fails it’s instantly. You open them up, close them, measurement is off, throw them out and grab a new one. I’m not using them to scribe and if I really need to do that, I grab the steel ones.
I wish I could buy a lefthanded version without paying the genius surcharge. Or more better one a caliper wich is switchable between left and right
The big difference, that this type of testing never can show, is that 10+ years from now expensive Mitutoyo, LS Starrett or Fowler calipers will very likely still be working within tolerances even with hard commercial QC inspector usage.
Depends, drop any caliper and let it land on the jaws and it will likely bend, measure a couple of thou off, from then on.
Cheap calipers are better for the butter fingered.
If you’re jamming the thing into a grinder, spraying dirty swarf-filled cutting fluid all over it, taking rough cuts to get closer to the final size, you grab the cheapest tool you can afford to lose.
When you have an inspection quality too like a Starrett, and you use it to verify customers’ parts all day every day, handling it becomes a ritual. You check its calibration every morning. You clean the part, bring the part to the bench, wipe the anvils, and take the reading. You wipe off the tool, then lay the measuring tool back down on a chamois or shop towel. Nowhere in the steps do you fling the thing around the shop, wave it over concrete floors, etc. And you do not drop it.
If you accidentally drill a hole into the table of your CNC mill the best fix is to engrave the word ‘OIL’ next to the hole.
‘Do not drop it’ is good advice.
What did you do last time you dropped an expensive measuring tool?
Also: ‘Inspection quality caliper?’
I think you mean micrometer or CMM.
Inspection with a caliper implies super sloppy standards.
Just eyeball it.
Average day at work, just wanted to put it back on the shelf. Man, cataplexy sucks.
It has been my experience that you don’t always get what you pay for, but you almost never get what you don’t pay for.
I went through 3 of the $10 Harbor Freight calipers in a period of about a year and decided to spend a little more. Now I have a $40 (just checked, they’re up to $52 now) iGaging absolute origin caliper that is precise and accurate. Unlike the HF junk, I don’t have to zero it before every measurement, the battery cover doesn’t fall off, and I don’t have to replace the battery more than once per year.
I also have a plastic dial caliper that is surprisingly precise and accurate, but only measures in inches, so is all but useless to me.
I like to say “You get what you pay for IF YOU’RE LUCKY”, but I really like the mrehorst version better. I’m taking it.
The first pair of harbor freight calipers I got, like 20 years ago, are a gem. Absolute origin, quite repeatable, don’t burn through batteries THAT fast. I used them constantly until the power switch finally wore out. All the subsequent ones I’ve gotten from HF have kinda sucked, not absolute, burn through batteries, barely worth the cost. That’s the other thing you get from mitutoyo: it’s going to be the same quality every time.
I’m a fan of dial calipers. Easier to read than vernier and no batteries. Also easier to do things like find the maximum or minimum width of that not-quite-circular part.
I second that.
Some dial calipers claim 0.01 mm, which I doubt; I think even at ~0.05mm it is still pretty good. Having said that, IMHO, dial is easier to read.
Project Farm is a great resource, but not perfect.
The guy’s voice is irritating.
The videos take too long. Tighter editing might help, but there’s probably no solution to the problem if the format is video.
One of the most important properties for some equipment is “how long will this last?” This critical data is often missing. In his defense, it’s often difficult or impossible to test for.
He occasionally steps outside his area of competence when dealing with electronics.
Despite my complaints, overall I’ve seen nobody doing a better job in this arena.
My complaint about having to watch a video when the results could be summarised in text seems to have been deleted. Oh well.
The ranking method does not strike me as useful. The scales are all wrong, it’s all just just A > B > C. Not telling how much more useful the top ranked device is to least ranked device.
Self discharge has probably an acceptable time frame totally unacceptable time frame, this video does not consider any of that.
I use a cheap digital caliper for designing things for 3D printing. Works just fine for my purposes.