Would you buy a second-hand micrometer?

[Bolster]

I understand they are easily damaged by over-tightening. Would you buy a used one? Or is this one of those tools that should be bought new?

If new, can you recommend a decent VALUE brand?

I know that question is an invitation for people to pump up their self-esteem and start bragging on the $1-bazillion-dollar brand they own, but I do not need top of the line (or junk). I'm looking for middle-of-the-road, bang-for-the-buck.

Thanks.

 

[nate379]

Starrett is pretty good and they aren't too expensive. I have a few I got from my brother (he is a machinist)

 

[Nealcrenshaw]

It depends on how accurate of a mic you need and/or the price of the used mic? If you're planning on using it for engine rebuilding or any other use that requires good accuracy you may want a new one. If not, a second hand will work.

 

[Diesel-Mech]

I would buy a used one, just be sure to check it with a standard prior to use.

 

[TejasBimmer]

If you get a decent manual version, it can be repaired...short of it being smashed or run over by a truck.

 

[Danglerb]

I would not have a problem buying a good brand from someone that looked like they knew how to treat tools, but don't they make test things to check them with?

Buying from a pawn shop or typically less savory location I would want it cheap enough to compensate for risk.

 

[Bolster]

Yes, needs to be engine-rebuilding quality.

I am seeing Starretts running $110 - $320 new. Is that considered a middle of the road, bang for the buck tool?

Can you recommend a standard to check the used ones I find at the 'markets and pawn shops? If, say, a half inch standard measures as .500, can I assume the rest of the range is OK?

And what tolerance does a used mic need to hold? If I am checking with a .500 standard, and it measures .499 or .501, is that a bad mic? Or is that within the range of measurement (or user) error?

 

[Vulturej]

I have bought several name brand ( NSK, Starrett, Brown & Sharp) micrometers used, all are measuring tools at work are calibrated quarterly and I never had a problem with any of them.

 

[Monte]

try mitutoyo

 

[Stuey]

No, I would not, unless it was sent in for calibration before transfer of ownership.

 

[Bolster]

I'm not working in a large shop where regular checks are the norm, so where would I go to get a used mic checked and calibrated? Is recalibration expensive?

YOU KNOW WHAT, I really asked the wrong question above. Let me try again:

"Tell me what I need to know before I buy a mic. Assume I am a mic noob, because I am." There, how's that.

 

[speed bump]

I would buy them used after some inspection and looking to see what kind of shape they are in. Used I would go for Brown&Sharpe, Lufkin, Mitiouyo and Starrett.

The standards are called gauge blocks, at school we have pretty complete set of the branded Starrett and Made in China. If it was for home use I would probably buy an inexpensive SPI set from MSC.

Tolerances should that it should hold now are based on what it can hold when which is generally printed on either the mic or in the literature with it and whats acceptable to you now. Personally if the mic was spec'd at +-0.00005" then I would want it to be pretty darn close to that across a couple of gauge blocks.

 

[Bolster]

try mitutoyo

Mitutoyos appear to also run $100-$300 new, same ranges as Starrett. Is that considered middle-of-the-road, bang-for-the-buck?

 

[Elroy]

What range are you looking for ?

 

[Kona Cruisers]

IMO ... there really isnt a midle of road.. its either good or ****....
Goood. Brown and Sharp, Mitutoyo, Starret

or ****!!!
and IMO blue point and fowler are ****, (one of the few times I think rebadged stuff from china *****!!!)....

you have to realize the diffence in build quality could be off just smallest of degrees and now the micrometer is ****....

 

[Elroy]

Personally if the mic was spec'd at +-0.00005" then I would want it to be pretty darn close to that across a couple of gauge blocks.

OUCH

that's 50 millionth !! That's half a "tenth" just a little extreme !

Your standard mic is only really good for .0001" and even that you need to read the vernier.

 

[voidifused]

http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=250395503767

I just got that one, its not a big name but it works perfect. We have a guy right in shop who does the calibration on all the tools, which is fine with me. I had one Brown & Sharp i sent in and had calibration coasts to much money i am cheap some days and i know machining tools are not things to be cheap with

 

[TheToolMan]

Dude take my advise. If you are a newbie them you dont need a $300 mic. Buy a second hand one that looks like it has been taken care of.

 

[old salvage]

As has been said, if buying a used mic, shy away from one that looks like it was used to measure polyps inside a Tyrannosaurs colon. If the mic looks clean and not abused then set it to about .002 and hold it up to the sky. Look at the space between the measuring surfaces while closing it another thousandth. Close a little more and see how the measuring surfaces touch. The surfaces should be very close to perfectly parallel. Open it back up a bit and do this again but stop at the exact point the measuring surfaces touch then read the mic. How much more or less than .000 is it ? If you are only measuring things that are flat then you can use the mic, just add or subtract the difference or adjust the mic to read zero when the measuring surfaces touch. If you are measuring cylindrical things then the mic may need service depending on how bad it is.
Either way the mic must be consistant throughout its range, that means checking with fixed gages at .125 .250 .500 etc.

 

[rodm1]

Mitutoyos appear to also run $100-$300 new, same ranges as Starrett. Is that considered middle-of-the-road, bang-for-the-buck?

what size you need? You should be able to get a new one for about $80. Do you need it know or can you wait for a sale?

Fowler is ok Mitutoyo (pg325) feels better in hand and arguable the best. I don't think Fowler comes with a standard. If not in a hurry Enco has 15% discounts every month or two.

http://www.use-enco.com
2 to 3 inch Model #619-3108 $36.99
3 to 4 inch Model #619-3109 $41.99
4 to 5 inch Model #619-3110 $46.99

 

[voidifused]

old salvage gets a cookie, Nice feed back

 

[Bolster]

Some good advice here, thanks guys. (A few answers: I'm not in a rush, need 0-1".)

 

[rodm1]

Some good advice here, thanks guys. (A few answers: I'm not in a rush, need 0-1".)

I would go with this. It don't come with those mickey mouse thimbles but if you practice measuring with drill bites you will get the feel of the mic in short time.

http://www.use-enco.com/CGI/INSRIT?PARTPG=INLMKD&PMPXNO=950223&PMAKA=600-2128

 

[old salvage]

old salvage gets a cookie, Nice feed back

Thanks. I'm not finicky either.
Chips Ahoy, Nutter Butter, Oreo,....

 

[-B-]

Yes I would and have .

what are you going to do with it ?
what range of measurement do you need ?
what read out do you need / want?

if you are doing automotive work use is the best way to go the minimal damage that can happen is well with in spec of automotive parts you only need to read to the .01 for them anyways.

more precision type stuff would be gun smiting, or home machining then you will need to get the best you can and will be reading down to .0001 more then that and you are in to aerospace and medical work

the best cheap small gauge blocks 1/4" grade 25 ball bearings they are held to .000001.

 

[Bolster]

what are you going to do with it ?
what range of measurement do you need ?
what read out do you need / want?.

1. Measure tolerances on machine parts, .001 will do me just fine for now.
2. 0-1"
3. Old School (not digital).

The ball bearing tip is great. Thanks.

 

[cnyeco1]

Buy Enco. Or shop the pawn shops. Most any mic. you buy can be adjusted with a mic wrench. With as many used ones out there it is dumb to buy new. I have 60-70 mics that i have bought as people quit or got fired and I didn't pay more than $20.00 for any Starret or $10.00 for any rice brand.

If you buy one that is off a little I'll help you calibrate it..

Cam.

 

[rhandwor]

They have test blocks to calibrate them with.

 

[crankshaftdan II]

Summer is fast approaching, if looking for a bargin mic check out garage sales etc. hoping to find an older retired machinist who is unloading his tools as he has no survivors to willtoo. Like previously stated by other mechanics, if the guys tools are clean, well kept and newer looking they are probably good used precision tools and people are not looking to get rich off of them, most good machinists will answer any questions you might have. You might have to haggle to get the price down to what your budget is, probably worth the effort. If the tools are rusty, nicked up and look like they were used for c-clamps or vice grips-stay clear of those tools!!!

 

[vssjim]

My nice stuff is US made Starret my cheapy stuff is US made Central

 

[Kevin54]

Yes I would and have .

what are you going to do with it ?
what range of measurement do you need ?
what read out do you need / want?

if you are doing automotive work use is the best way to go the minimal damage that can happen is well with in spec of automotive parts you only need to read to the .01 for them anyways.

more precision type stuff would be gun smiting, or home machining then you will need to get the best you can and will be reading down to .0001 more then that and you are in to aerospace and medical work

the best cheap small gauge blocks 1/4" grade 25 ball bearings they are held to .000001.

Any mic you get is going to read in .001 and not .01

And cheap gage blocks are not that close. You have different grades of blocks. Inspection Grade, Grade 00, Grade 0, Grade A, Grade B.
A cheap set will give you a tolerance of .00005. Even at that, you cannot measure that small of a dimension with an 0-1 mic.

 

[Bolster]

You sold me on the cheap set of check blocks!

Where do I find them?

 

[rsanter]

I have developed a prefrence for Mitutoyo
however some of the other brands others have brought up are very good as well

buy used?
I think its the same as buying a car. you look it over the best you can and get one that has been taken care of. even at that there is some risk when buying used.
if the Mic is overall in good shape they are not hard to calibrate. any Mic you have should have a standard to go with it so you can check it at its minimum measure and I also like to check it at the max measure as well.
keep in mind that even for most the basic stuff you will do, you do not need as much precision as you might think you do (unless you are doing high end engines)

bob

 

[Vinko]

MSC had a code for measuring tools not too long ago, didn't they? I just got a Mitutoyo depth gauge (digital) and a micrometer (analog!)

Bolster: we have some Starrett tools in our shop, which are considered among the best. They were my father's old tools. I'm not really qualified to give a mini-tutorial on the micrometer, but a machinist uses "feel" when he uses the tool. Using at least an old Starrett tool, you can "feel" exactly where you need to adjust to read, say, the thickness of a piece of paper.

Someone mentioned SPI (Swiss Precision Instruments) -- I saw their booth at a recent trade show. I don't know anything about them.

I do know that there's a reason that machinists generally zealously guard their tools. We've got a few for general use in a production environment and they're not treated as well as I'd like them to be.

Starrett has a book for the "Student Machinist" that you can buy used that will teach you how to use all sorts of tools.

 

[Kevin54]

You sold me on the cheap set of check blocks!

Where do I find them?

Many companies carry them. But you are looking at a few hundred on up to a few thousand for gage blocks. If all you are wanting to do is get an 0-1 mic, then you can get 1 block to check it to. Normally if you close the mic down gently and it reads "Zero" you should be fine. But if you want a mic that you can actuallt verify yourself, look for a mic in a case that has the "standard" with it. This will be a calibrated 1" long bar that will be marked as such, probably 1/4" in diameter. This stays with the mic so you can periodically check it. One thing to remember....different style mics have different feel. Some will have a ratcheting thimble at the top so you don't overtighten the mic. Others do not. A Brown & Sharpe will feel different than a Starrett, will feel different than a Mitutoyo. And everyone develops their own feel with their own mic. You'll find that out. But for buying a mic, you can pick up good used ones everyday. EBay, Craigslist, local paper advertiser, etc. Like I said, if you close one down and it reads "Zero" chances are it is good, if you close one down (very lightly) and it is off .001 or more then it has been drawn down too tight. That is bargaining room if it is for a talk down in price. An 0-1 is pretty hard to destroy. I had an old one that I really torqued to see how much it would change. I could easily spring it .010 but it would come back. You just don't want to buy one that is that far off though to be safe.
BTW to anser the original question about buying second hand mics.....that is all that I have. From 0" all the way up to 6". And I keep my own calibrated.

If you insist on a set of blocks, check with a place like Travers. They usually have some special deals. MSC alweays runs sales too.

Check this on blocks...... http://www.mmsonline.com/articles/gaging-is-baseless-without-standards.aspx
http://en.wikipedia.org/wiki/Gauge_blocks
http://www.1gg.com/html/tipsqc.html
http://www.starrett.com/pages/1338_primary_standards.cfm
http://search.globalspec.com/ProductFinder/FindProducts?query=Gage%20Blocks

 

[OldCarGuy]

I would suggest that anyone purchasing micrometers for the first time to purchase a good used set. Take along an old timer to evaluate them for you.

It takes a lot of experience to learn the proper technique to get accurate readings from micrometers. You just don’t use them like “C-Clamps” to get a reading. You need to learn “The Right Feel” when measuring across the thickness of a workpiece. There are also a number of factors to take into account too. Such as surface finish, Hardness, shape, and temperature of the workpiece.

I have a nice used six-piece set to 6" of Micrometers for sale in the classified section. They have carbide tips, reads in tenths (.0001"), locking, ratchet thimble, with standards, in a fitted wooden box. Made in China. Used and in good shape $100.00

 

[Uncle Buck]

Buy Enco. Or shop the pawn shops. Most any mic. you buy can be adjusted with a mic wrench. With as many used ones out there it is dumb to buy new. I have 60-70 mics that i have bought as people quit or got fired and I didn't pay more than $20.00 for any Starret or $10.00 for any rice brand.

If you buy one that is off a little I'll help you calibrate it..

Cam.

Heck man, if you still have 60-70 mics why not show the boy some love and sell him one for like $20 plus shipping or something. With that many laying about surely there are a few decent ones you are not that strongly attached to!

 

[caper]

If the mic looks clean and not abused then set it to about .002 and hold it up to the sky. Look at the space between the measuring surfaces while closing it another thousandth. Close a little more and see how the measuring surfaces touch. The surfaces should be very close to perfectly parallel. Open it back up a bit and do this again but stop at the exact point the measuring surfaces touch then read the mic. How much more or less than .000 is it ?

You could close it on a feeler guage,it's a known thickness,to get an idea how accurate it is.

 

[slack]

I have mics from Mitutoyo, Starrett, Brown & Sharpe, Tesa, and others. They are all good mics. Starrett is good stuff, with a long US history, though often gets erroneously referred to as top of the line on this board. Just like any maker, some of their stuff is great, and with other items there are better options. Mitutoyo is probably the most used precision measuring tools in manufacturing around the world.

I wouldn't have any qualms about buying used. They are either in decent condition and work well or the don't, and they are either accurate or the are not. When considering a model you might look for carbide tips, as they are more durable and can make the instrument accurate longer in harsh use. However, it doesn't matter how accurate a mic is, you have to develop a feel for using one. Just about any you can afford, no matter the quality and accuracy, can provide an inaccurate reading, even when closing on itself or a gage. If you over-tighten or close too lightly you will not have an accurate reading.

 

[Major Ramifications]

Buy Enco. Or shop the pawn shops. Most any mic. you buy can be adjusted with a mic wrench. With as many used ones out there it is dumb to buy new. I have 60-70 mics that i have bought as people quit or got fired and I didn't pay more than $20.00 for any Starret or $10.00 for any rice brand.

If you buy one that is off a little I'll help you calibrate it..

Cam.

60-70!? Maybe you should start going to meetings! "My name is cnyeco1, and I'm a micaholic."

I would have and have had no problem buying used measuring equipment. It seems that when buying new, there is cheap and expensive, nothing in-between. I regularly hit the pawn shops for good quality equipment that looks well taken care of at a good price. Ebay is another good source. I am currently in the slow process of blueprinting an engine for my truck, and haven't needed to measure anything past two-and-a-half ten-thousandths (0.00025). Actually my micrometers only measure to the thousandth (0.001"), but it is easy to figure the ten thou digit by seeing where the line lands. Does that make sense?