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rohamm
04-17-2012, 10:01 PM
I just tossed my electronic mic because it was discontinuous: winding down through .750, it jumped to .733 which explains some of my recent woes.

Looking on the web, there appear to be only a couple different-looking choices. I plumped for an iGaging mic from Rockler woodworking as it was only $30 shipped. It's much nicer than my old one: it has an on/off button whereas the old one would supposedly shut off automatically unless the battery was weak - kind of perverse, I thought; the new one requires you to hold down the zeroing button for a while so you don't end up accidentally zeroing it while handling it.

A Starrett piece for a little over a hundred looks just like it. Do you suppose Starrett do anything beyond stamping their name on it, or do they somehow make it less likely to fail in the future? Maybe they have an agreement with the factory to ship them only the kind that don't crap out in a short while.

macona
04-17-2012, 10:38 PM
Micrometer or caliper?

A assume caliper. I like mitutoyo. Buy a good one and it will last you a long time. Check pawn shops, thats where I found my mitutoyo.

Jaakko Fagerlund
04-18-2012, 01:00 AM
MIB in Germany also makes good instruments, check them out.

Maybe that electronic mic has some crud in it if the reading jumped all of a sudden?

Paul Alciatore
04-18-2012, 03:44 AM
I have a Fowler and am quite pleased with it. No problems for over a year now.

Doozer
04-18-2012, 09:17 AM
+1 on the Fowler micrometer.
I found one in the chip barrel at work,
and it was funky from being wet with coolant.
I dried it out, replaced the battery, and it
has been good to me for a few years now.
Digital mics are great to readily see tenths of
a thousandths for close work, which is the
reason to use a mic. I know vernier mikes
exist, but not handy to read them around
the back side when looking at lines.
--Doozer

JCHannum
04-18-2012, 09:29 AM
If you purchase low end measuring instruments, you will get low end results. Just because some chicom manufacturer makes a micrometer or caliper that "looks just like" a Starrett does not mean it has any relation to Starrett. It is a gimmic to suck the uninformed purchaser in.

Starrett does make tools in China, but they are manufactured in the Starrett facility under Starrett supervision.

Dr Stan
04-18-2012, 10:16 AM
If you purchase low end measuring instruments, you will get low end results. Just because some chicom manufacturer makes a micrometer or caliper that "looks just like" a Starrett does not mean it has any relation to Starrett. It is a gimmic to suck the uninformed purchaser in.

Amen says the choir.

uncle pete
04-18-2012, 11:47 AM
And you also need to watch for counterfeit brand name precision tools. Mitutoyo for one has a warning on their website about them. Their almost exactly the same in looks. Lot's of them have been sold on Ebay all over the world. If it's brand new and selling for a unbelievable cheap price? You might want to be real careful.

Accuracy and dependability costs. That's just a fact of life.

Pete

Carld
04-18-2012, 12:51 PM
I do not trust digital micrometers and calipers. Unless each one costs as much as the DRO on my mill I would not trust them and even then I may reach for a manual mic to back up the reading. Thinking that way why would I ever want to use a digital mic or caliper, and your right, I don't and won't. I may trust the $1000+ Starrett mic's because I do trust my DRO.

The price is a good indication as to quality and dependability.

Bill McLeod
04-18-2012, 02:28 PM
I really like my Mitutoyo caliper [CD-6"GS], it's great and gets a lot of use. The cheap digitals are good to carry around in my truck to get a so so measurement on something before I get it to the shop. For getting a final size I use a tumbler micrometer. Cheap tumbler micrometers once checked against a standard are fine with me and have never given me trouble, definitely not so with cheap calipers electronic or analogue. When buying a electronic caliper you'll save money buying IP65 coolant proof. Yes Macona your right I also like pawn shop mics I carry a 2" standard in my truck to take "shopping".

PeteM
04-18-2012, 02:37 PM
I've owned digital micrometers from Mitutoyo (several), Starrett, Fowler, Moore & Wright, and (one) no-name Chinese brand. Of these, the Mitutoyo has been by far the best. Compared to the Chinese import it has about 10x the battery life and updates faster. One of the Mitutoyo's is now ten years old and still going strong.

The Starrett looks cool, but requires more expensive batteries which don't last as long. The Fowler I have is so-so. The M&W is so old as to make comparisons not so meaningful. Bottom line -- get a genuine Mitutoyo. The electronics in Mitutoyo digital calipers are also recognized as the best. Again, don't buy a Chinese unit -- the circuit board looks rougher (I've had them apart), the anvils may be slightly out of parallel, and it will likely eat batteries.

The upside to a good digital mic is instant US/metric conversion, the ability to do +/- measurements, and easier and faster reading. The only downside is that it is bulkier and will require a coolant proof version in the unlikely event you measure items amidst flood cooling.

RWO
04-18-2012, 03:36 PM
+1 on Mitutoyo digital calipers. They have the digital caliper technology nailed. I just bought a new 6" and it is miles ahead of the first model one I bought many years ago. I love the fact that I can turn it off and it still knows where it is when turned back on, no matter where I have moved the slider jaw.

RWO

dian
04-18-2012, 03:41 PM
i still dont get it. is this about digital micrometers on digital calipers? oh yes, i have a digital calculator, but it doesnt eat batteries, because its solar.

beanbag
04-18-2012, 04:17 PM
I just tossed my electronic mic because it was discontinuous: winding down through .750, it jumped to .733 which explains some of my recent woes.


My guess is that the encoder wheel thing was too far from the sensor thing. You could have opened it up and fixed that.

Evan
04-18-2012, 05:14 PM
I do not trust digital micrometers and calipers...


Neither do I and I am well versed in things digital and electronic. I much prefer mechanical measuring tools for a number of reasons not the least of which is that the batteries last exactly as long as I will. Trends, splitting the marks and being able to trust the reading are other reasons. The ability to very accurately transfer measurements is another. The ability to read the measurement without having to interpret it is yet another.

Last night I was sorting drill bits and I don't have to read the caliper at all. I can very reliably tell the difference by eyeball if the bit is 0.1" larger or smaller than 0.25". If the needle is pointing straight down then it's a 1/4" bit. I don't even need glasses to see that much.

Bob Fisher
04-18-2012, 07:04 PM
Using a Mitutoyo digital mic today, touched the zero button accidentally, and lost my reference. Thankfully, you can read it manually, but is a real pain to wind back to zero to reset. Zero and unit buttons should be sunk to prevent accidental contact. Bob.

jdunmyer
04-18-2012, 08:22 PM
My experience with digital measuring equipment, FWIW:

Mitutoyo caliper: worked great, gave it to a friend and replaced it with:

Brown & Sharp caliper: after a very short while, it got flakey, would lock up or lose zero, requiring the battery to be R&R'd to get it going again. For a short time. Can't even think about using it.

3 cheapo calipers: all work great, are repeatable, accurate to .001" over guage blocks. Why 3? Got one at a N.A.M.E.S. show several years ago for $15.00 or so, just to try. Bought a 12" version at H.F. Tools because I needed the range. Third one came from the N.A.M.E.S. show last year because I couldn't resist the $10.00 (w/o battery) price. It "wakes up" upon the slightest movement and has a larger display than the first cheapy, so has become my favorite.

Mitutoyo micrometer: I really like this unit except it's kind of heavy and bulky, plus it eats batteries. Have to guess, but they're probably only good for a couple of months, so I quit using it altogether.

Mitutoyo readout on the quill of my B'Port: works great, battery lasts for several years.

YMMV:

Black_Moons
04-18-2012, 08:33 PM
+1 on Mitutoyo digital calipers. They have the digital caliper technology nailed. I just bought a new 6" and it is miles ahead of the first model one I bought many years ago. I love the fact that I can turn it off and it still knows where it is when turned back on, no matter where I have moved the slider jaw.

RWO


Er, Every $20 digital caliper I have ever bought remembered zero when off.
Most butteries (Cheap dollar store alkaline, about 5 for $2.50) last a few months for me.

Only time it gets flaky is when the battery is nearly dead, but then as it typically jumps entire inches multiple times a second when moving the jaw, its hard not to spot.

beanbag
04-18-2012, 08:59 PM
I am very happy with my cheapo digital calipers and micrometer. The one time I had a nice analog caliper with a dial, I dropped it, and it never worked quite right again.

whitis
04-19-2012, 03:56 AM
Er, Every $20 digital caliper I have ever bought remembered zero when off.
Most butteries (Cheap dollar store alkaline, about 5 for $2.50) last a few months for me.

Only time it gets flaky is when the battery is nearly dead, but then as it typically jumps entire inches multiple times a second when moving the jaw, its hard not to spot.

Many of the complaints about these chinese calipers seem to stem from using substandard batteries.
http://bbs.homeshopmachinist.net/showpost.php?p=521438&postcount=66
Good battery: 8-14months, depending on caliper
Bad battery: 2-12 months, depending on caliper

EVguru
04-19-2012, 05:40 AM
Er, Every $20 digital caliper I have ever bought remembered zero when off.

There's a very simple reason for that.

THEY WERE NEVER OFF! Only the display is blanked. That's why the batteries don't last like they do in a Mitutoyo.

I've picked up some real bargains from the faulty/clearance table by taking them over to the remote displays and seeing if there's a data stream. If there is, it's often just a missaligned LCD. At the very least the instrument is usable with a display connected.

macona
04-19-2012, 06:45 AM
Er, Every $20 digital caliper I have ever bought remembered zero when off.
Most butteries (Cheap dollar store alkaline, about 5 for $2.50) last a few months for me.

Only time it gets flaky is when the battery is nearly dead, but then as it typically jumps entire inches multiple times a second when moving the jaw, its hard not to spot.

Thats because they don't really turn off, it just turns the display off which basically takes no power.

oldtiffie
04-19-2012, 09:14 AM
Using a Mitutoyo digital mic today, touched the zero button accidentally, and lost my reference. Thankfully, you can read it manually, but is a real pain to wind back to zero to reset. Zero and unit buttons should be sunk to prevent accidental contact. Bob.

As part of the job I make a reference if I don't have one on hand. Its easy to re-set. I check mine every time I turn it on - using either the spindle on anvil (reference zero) or over the made/shop reference (job reference).

In all cases when using a reference the micrometer or caliper is being used as a comparator and not as a definitive measuring tool.

jdunmyer
04-19-2012, 10:37 AM
You're correct about the batteries. Don't ever use the LR44's, they're junk. In fact, when I bought that $10.00 caliper at the show, they were selling it for "$15.00 w/battery, $10.00 w/o". The battery was an LR44, and they seemed happy enough to sell the caliper w/o it. As I had SR44's in stock at home, I went that way.

At $10.00, I can have one of these every place I might need it. It also allows modifications like I've seen Sir John do on one of his. I don't remember just where it was, but perhaps John can refresh my memory.

Again, maybe Mitutoyos are "better", but I've sure not been able to verify that. I've used both guage blocks and mic standards to check the calipers, and they all check out fine.

When it comes to regular micrometers, I do prefer my old Lufkin with the friction thimble. It's light and easy to read. I have 2 or 3 old Starrett mics, but they're not as nice to use. The Chinese mics are laser engraved or somesuch and are harder to read (for my old eyes, anyway).

As an aside, if you have either old mics or Chinese mics, they're helped a bunch by cleaning the screw and lubing with Starrett Tool and Instrument Oil.

interrupted_cut
04-20-2012, 07:06 PM
I just ordered some Duracell brand SR44 batteries from onlybatteries.com. They have a special right now: 30 batteries for $22.99, regularly $74.99. I ordered some other batteries they had on special that I needed to spread the $12.95 shipping costs a little further. Still a pretty good deal for name brand batteries.