nice mitutoyo calipers that were on sale

[larry42]

Question is (and I don't mean to be smart alec about it), since you are doing custom boxes with it, do you really need 0.0001 inch precision?
 
It would be rather hard to make a box to that kind of precision.  I have not measure exactly, but having file aluminum as most have...  Say filing down a hole in an aluminum box, one extra movement of the file will remove a good bit more than 0.0001 inch.

I fully understand "just to have it", I don't need better than 5% accuracy but I got a DMM with much higher resolution than 5% "just to have it.  I assume that is the case?

To elaborate on a previous answer regarding a factor of 10 more accuracy than needed:

I don't do much mechanical work but as you say, you don't need 0.1thou (=0.0001inch) precision. However, don't worry - with ordinary grade vernier calipers you won't get that. I just bought a Mitutoyo 530 series (standard analog) - there are the same precision as most digitals. That is to say, 0.03mm accuracy, 0.02mm scale  - that is 'only' ~1thou accuracy. Now if you take a couple of measurements, from different edges, to get the dimensions of the box and each measurement is off by a fraction of a thou', that adds up to perhaps 0.1mm, which is about where I would aim to be. If you are then drilling holes to fit M2.5 hardware, being 1mm off is pretty noticeable!

With multimeters, in my professional option, 0.1%-0.5% is about the right precision for a multimeter in a standard electronics labs - this gives good confidence that then 1.20V supply line is well within 50mV (or 5V line is within 100mV), without having to calculate error margins, and thus in turn is makes fault finding easier (is a supply lower due to more current being drawn, or is it just today's measurement error). For my kitchen multimeter, 1-5% is fine. Similarly for my living-room calipers (digital), a slight play in the mechanism of 0.1mm is fine.

[zapta]

Here are my results, average current draw testing on 6 sets of these.
Sold as Skillmeister Brand, tested with Agilent U1272A.

On pulsating 18-20ua
Off pulsating 17-19ua

Also they will draw about 45ua when any button is pressed.

Now this may not seem to be a big problem for some users of
this product, but I have found that they chew batteries compared
to the mitutoyo's and other brands that I use on a daily basis.

The mitutoyo doesn't have auto shut off, right? This can be a battery drainer if I will forget to turn it off (and I will). Have you had a chance to measure the mitutoyo's current consumption when leaving it on?

[miguelvp]

To miguelvp.

You might want to check the current draw of this brand of vernier caliper,
I think you will be suprised at the results between the on and off states.

Here are my results, average current draw testing on 6 sets of these.
Sold as Skillmeister Brand, tested with Agilent U1272A.

On pulsating 18-20ua
Off pulsating 17-19ua

Also they will draw about 45ua when any button is pressed.

Now this may not seem to be a big problem for some users of
this product, but I have found that they chew batteries compared
to the mitutoyo's and other brands that I use on a daily basis.

They are good value calipers except for this issue, general use only.
Battery must be removed when not in use. (Pain in the ass)

Relevant only to the vernier's that miguelvp displayed, not the mitutoyo's.

Muttley

I don't have a power supply, and it seems my mA fuse is blown, I have another DMM around but after cleaning my home office so it's presentable for Xmas I've misplaced it.

Edit: found it.
18 uA while on
16 uA while off
Button press if I hold it down 82 uA, but I rarely have to press any buttons and off course I don't have to keep holding them down when operating them so it's not really a concern.

Sliding the caliper stays in between 17-18 uA

Removing the battery zero's the caliper BTW, and applying power turns the caliper on by default.

Now I wonder why my main meter fuse is blown, it's only rated at 200 mA so maybe I measured something in haste and didn't go to the Amp range first, or maybe the fuse is dislodged but I doubt that.

[Muttley Snickers]

To Zapta.

The only Mitutoyo's that I have at hand are the 500-674c series (300mm) and run two batteries is series, so a comparison of current draw is invalid.

Also there is a large selection of models in the Mitutoyo's and I think you will find that most user's agree that the battery life on these units is more than excellent.

I have only pointed out that the unit that miguelvp displayed generally have an issue with battery consumption and I know this from experience with the product. I had two samples sent both 200mm and 300mm, was satisfied with the samples so we ordered 15 x 200mm and 15 x 300mm, after 10 days of intermittent use they needed new batteries, rinse and repeat. So we sent back most of the order. Kept a few as a reminder never to buy these again, documented the problem and notified the supplier.

Muttley

[zapta]

To Zapta.

The only Mitutoyo's that I have at hand are the 500-674c series (300mm)
and run two batteries is series, so a comparison of current draw is invalid.

Thanks Muttley, any chance of measuring the current of your Mitutouo and reporting here?

[miguelvp]

To Zapta.

The only Mitutoyo's that I have at hand are the 500-674c series (300mm)
and run two batteries is series, so a comparison of current draw is invalid.

Thanks Muttley, any chance of measuring the current of your Mitutouo and reporting here?

And please include the current consumption when it is off as well, just to know if it's an always on unit or if it actually shuts all the way off.

[Muttley Snickers]

A nightmare of a test to conduct, the thing's I do for you bloke's.

Had to use min/ max, reading's were a bit to quick to see.

Min 10.52ua
Max 222.32ua (intemittent peak pulse)
Avg 28.20ua

Off state reading's are just to hard for one man, clips wont stay on, might have another go later on today, not an important test really.

After about 30 seconds the unit seemed to be happy at around 20ua, the 500-674c uses two SR44 1.55 volt coin cells.

Muttley

 

[miguelvp]

Thanks, I know about the nightmarish test, even with one battery it was an ordeal for me using a DMM and trying to measure and operate the caliper without clips, a power supply would have been easier for testing.

At least I didn't loose any of the two tiny screws that hold the battery in, that's my major gripe about my caliper.

As for the off state I think it's the only important test to see how much it depletes the batteries while not being used. Mine consumes almost the same as when in use (16uA vs 18uA)

It came with an spare battery and the other one already installed which I have not replaced yet but I have no idea how long it's been in there. So in my case auto shut off only saves 2uA maybe because the only thing that shuts off is the actual LCD display and little else.

[Muttley Snickers]

To miguelvp

I don't mind these cheap calipers for just run of the mill stuff, and if they get knocked off the work bench I don't give a stuff for what we paid.

Originally, I did pull a set apart to see if I could install a jumper link as a battery isolator, but I do have some nice sets in other brands and gave up on these for other reasons as well.

Muttley

[monkeysuncle]

I have a Mitutoyo 500-196 that I bought several years ago on sale for about $75. My biggest complaint is that they do not have an auto-off feature, unlike my cheapo Harbor Freight calipers. I'm not good about remembering to push the off button when I lay them down, so I have found that the HF calipers are much more likely to have working batteries the next time I pick them up. The HF also turns itself on automatically when I slide the head, whereas on the Mitutoyo I need to push the button.

And even though they use an incremental encoder, I find the HF usually remembers its zero point between uses.

In highly informal testing, I have not noticed any differences in the readings between the two calipers.

So on the whole, I hate to say this, but I reach for the HF more often.

--Dan Menes

[zapta]

This Mitutoyo caliper uses solar cells instead of batteries. Anybody has any experience with it?

http://amzn.com/B002SG7QN8

http://www.mitutoyo.com/pdf/1814SuperSolarCaliper.pdf

[zagnut]

don't care for the absolute feature myself...the OCD in me will zero it whenever it gets turned on anyways. 

out of all my calipers i prefer to use my ancient mitutoyo digimatic even though the display is tiny compared to the newer ones.  have had it for twenty years and it was used when i got it.  battery lasts for years.

the ones starret makes (or rebrands) totally suck in comparison, i have an older chinese one i prefer to those.

[Paul Moir]

It doesn't matter anyway.  All the on-off switch does is turn off the LCD, saving practically nothing.  It's there just to make you feel good.

The controller has to be up and running normally at all times or else you would have to rezero the callipers every time you turned them on.  No-one wanted that so that design is pretty much abandoned now.  The absolute worst ones would auto-off on you and loose their zero, and so also your measurement.   

Hold the calipers up to a light when you zero them.  That way you'll be able to see if a bit of dust is stuck between the jaws.  You can easily see a 0.00025" / 0.005mm gap that way.

It seems to me that some of the cheap digital ones are getting cheaper.  Some now have no gib adjustment to square the jaws and are so floppy getting a reliable measurement out at the tips is impossible.  Others have gib screws directly grinding into the beam.  The cheap mechanical ones don't seem as bad.  I kind of prefer these if not switching between SAE and metric.  No batteries and you can interpolate a bit between markings, and rocking to get a correct inside measurement is easier.  I go to the store with a gauge and exploit the bell curve to find a decent one.  Normally they do need a little work (~ 1hr) with a stone on the beam to get the gibs set nice without binding somewhere along the beam.  Would not buy a cheapy I couldn't try out though.  Not with Mitutoyos at an affordable price.

[SeanB]

The largest micrometer I have. Goes to 650mm with an accuracy of 1/50mm. A little hard to use on small parts, but was perfect to mark a board for cutting.

[Rick Law]

Thanks, guys...  Learned something here.

I hand-(re)made a couple of boxes, and I was not able to get better than 1/16" with my hole positioning.  So, 0.0001 looked way over-done for me.

I see your perspective now.

Rick

Question is (and I don't mean to be smart alec about it), since you are doing custom boxes with it, do you really need 0.0001 inch precision?
 
It would be rather hard to make a box to that kind of precision...

To elaborate on a previous answer regarding a factor of 10 more accuracy than needed:
...
...

...

...
...
The problem is not that the cheaper ones are only accurate to 0.001 whereas Mits are good for 0.0005... the problem is that the <$20 ones are so cheaply made and with such bad QC that it might be within 0.001 one time, then the next time off by 0.050
....
...
 measurement tool that is your last line of verification and control over your work.

That mic isn't +/- 0.0001" precision. The last digit is 5 or 0 for +\- 0.0005".

The rule of thumb (which I would argue is over-conservative) is that a measuring instrument needs to be 10x better precision than the dimension one is trying to measure, so the OP's  Mitutoyos aren't out of line at all for enclosures.

I'd also add that they're a lifetime investment if cared for.
...
...

[zapta]

watching amazon, this season, these things popped up on 'gold box' sale.  $80 on sale (normally over $110).  oh, sure, why not.  I like having nice test gear, and since I am doing a lot more custom box-building these days, might as well have some trustable measurement tools.

even the plastic box feels like quality.

(this is the item: http://www.amazon.com/gp/product/B00IG46NL2 )

Got this caliper from Amazon, together with this iGuaging absolute caliper http://amzn.com/B00INL0BTS . The best of the two will stay here.

One problem I have with the Mitutoyo is that that little push wheel seems to get stuck. It rolls when I push it to close the jaws but it doesn't disengage if I keep pushing it once the jaws are closed. My understanding it that it should disengaged and turn freely once the target force is reached.

If I hold the Mitutoyo horizontally horizontally with the jaws point down and then push the push wheel up it stays there stuck rather than falling back down.

Is it normal?

[robrenz]

One problem I have with the Mitutoyo is that that little push wheel seems to get stuck. It rolls when I push it to close the jaws but it doesn't disengage if I keep pushing it once the jaws are closed. My understanding it that it should disengaged and turn freely once the target force is reached.

That is normal, it is not like a friction thimble of a micrometer

If I hold the Mitutoyo horizontally horizontally with the jaws point down and then push the push wheel up it stays there stuck rather than falling back down.   Is it normal?

Yes

[IanB]

Got this caliper from Amazon, together with this iGuaging absolute caliper http://amzn.com/B00INL0BTS . The best of the two will stay here.

Gaah! I hate when people try products out and then send them back. The one you return will become an opened box, used item that someone else will receive "as new".

[SeanB]

No consumer protection laws in the USA? Here it will go on the reduced price stock list for sale at either a slight discount or will be kept for the periodic sale shelf.

[IanB]

Amazon doesn't do that. When you buy something from Amazon there is a chance that you will receive a previously returned item. OK, you can send it back and ask for a replacement, but it's a hassle.

[zapta]

Gaah! I hate when people try products out and then send them back. The one you return will become an opened box, used item that someone else will receive "as new".

I first ordered the iGuaging but it was notchy so ordered also the Mituyoto, all in good faith.

It's not for you to determine Amazon policies. For some products they even pay the return shipping to encourage people to try to compete with brick and mortars. Don't like it? go somewhere else.

http://www.amazon.com/b?ie=UTF8&node=8622296011

[Robomeds]

Interesting thread.  I'm glad that video with the iGaging calipers was included.  Over the past few years I've messed with calipers from quite a few brands including a few generations of the Mitutoyos.  In general I think the Mitutoyos are the best.  For the most part I can't suggest any other brand IF you want to spend the money.  In addition to having a few Mitus we also have a Starrett and Tesa/Brown and Sharpe Shop-Cal at work.  The Starrett and Tesa are of similar build quality to the Mitu but they lack the absolute feature.  It's just nice to not have to think about zeroing the caliper every time you turn it on. 

The Tesa does have a crude work around.  When you first turn it on the display flashes a zero indicator.  Thus if you turn it on near but not at zero you won't think it's actually zeroed (this is a problem with the cheap calipers).  It has an auto display off but retains power (and thus zero) for about 2 hours.  Then it will power down unless you put it in ABS mode.  In that mode it will stay on until the battery is dead.  Thanks to the 2032 lithium cell that battery lasts as long as the Mitutoyos even though it's not as power efficient.  Then again, 2032s are cheaper than RS44s. 

Something I don't like about the Tesa is the single button interface.  The three button functions are all handled by one button depending on how long you hold it.  Well, in the US I switch between inches and metric frequently so that 2 second delay actually is rather annoying.  If you release early you zero the caliper.  It's much nicer to have the extra buttons. 

In addition to the lower end models of the good brands (all around $90-120 street price) I've used several of the Chinese models.  The video showed two iGaging models.  We have some of the large display ones that got second.  They are under $25 from Amazon and a VERY good value.  The guy is right, they don't have the cheap feel of the $10 models.  Their build is really quite impressive for the price and in most cases I would have trouble suggesting any of the more expensive brands over the iGagings.  My personal Mitutoyos are better but I own them only because I got a great deal on them (used, oddly listed on ebay).  I tested the iGagings against the Mitus and found that they had no accuracy advantage.  The feel was OK but not as good.  Still, for a near $100 savings that would have been that were it not for the ebay deal I found.  It doesn't hurt that the fractional stuff is useful from time to time.  I would be curious to try the Absolute model. 

The other, cheaper Chinese models seem to be a mixed bag.  My first pair was reasonably well machined (almost as good as the Mitutoyos) and cost perhaps $25 about 8 years back.  They actually were dead on when measuring a gauge pin while my work provided Mitus were one count off (both in spec).  The Chinese ones did eat batteries.  I was going to suggest those calipers for a school lab a few years back but the design was changed.  The newest ones (and these are similar to the current Harbor Freight models, not the HF ones from about 5 years back) have VERY crude finishes on them.  When the jaws are closed the depth measuring tail was 0.007 out of flush.  While I have no doubt that sliding the head 105mm would result in a reading 105.00mm greater than it started, I can't trust that the jaws are square or close properly etc. 

My biggest concern is that some versions of the generic Chinese models seem acceptably good while others are VERY crude.  With out a hands on I can't tell which is which.  The old HF and the new ones look almost the same yet I can see why the calipers are now half the price they were just a few years back.  Anyway, this is why I would suggest the iGaging over the other cheap brands.  It's hard to say "spend $120 vs $10" to someone who doesn't really need the all 4 measuring surfaces to be perfect and doesn't mind picking up 10 LR44 cells for $2 to match the same battery life a Mitutoyo will deliver off one $2 battery.  But it's easy to say avoid the $10 stuff and step up to a $24 caliper that is almost as good as the $100+ stuff. 

That or wait for the rare "Craftsman" or other relabeled Mitutoyo to come up on ebay.  Yes, just as you can occasionally find a "Matco" labeled Fluke 87, Mitutoyo did custom label jobs.

[zapta]

Is the Mitutoyo really absolute? Mine required zeroing after inserting the battery. The iGuaging didn't.

[Muttley Snickers]

I posted this stuff in another thread (Fake Flukes) but I think that it belongs here.


Edit: Replaced Mitutoyo Imitation Leaflet PDF.

[HighVoltage]

What a world,
Fake Mitutoyo calipers?

And since not all fakes will look the same, it will probably get harder and harder to see the difference and even identify a fake.