I would just like to know what a good/thrifty brand of micrometer to buy. I saw I believe a three micrometer set by snap-on that was over $300 I know they are a good brand but I was hoping to find a much cheaper alternative also I only needed one size right now. I know you pay for what you get most times so I'm not completely naive that there might not be to many options for a cheaper piece with comparable quality.

 

You can get Chinese-made micrometers on eBay for rediculously cheap. The quality is more than adequate for non-professional use.

 

Buy a cheapo chinese set:

Why? Because it all runs on precision threads, the threads will be very precise (atleast +/- .0005) even cheapo ones. Make sure you get one with MASTERS for all sizes. You can get a 0"-6" for $100 and under.


The reason to buy a "quality" set:

Longevity (they can handle everyday the use)


Are you going to use them more then 100 times a year? If so, get a quality set.

 

You can probably just get the one size you want, (assuming it's 0-1", that's the most common) from harbor freight.

 

For engine work 0-1" is almost useless. 2-3" is good for measuring crankshafts, and 3-4" and 4-5" are for bore measurements.

 

if you are going to measure more than 1 inch i would recomend getting a 0-6" caliper. you can use it to measure inside and outside diameters, and depth. you can find one of these on ebay for like $80 BTW i recomend mitutoyo or starrett. i work at a machine shop and it's my weopen of chice

 

Calipers are nowhere near accurate enough for engine work.

 

Guys i really appreciate all the the replies. I had looked at the ones on ebay and they were really pretty cheap so I figured their quality was questionable even for my limited use. Also I already had a pair of calipers but they weren't accurate enough. Plus always nice to add a few new tools to the collection.

 

For bore measurements, you'd use the micrometer, along with a bore gauge right? Throw the bore gauge in, then pull it out and measure it with the micrometer?

Yea, a caliper is ok for most things, but not bearing clearances. Most calipers are ok to .001", micrometers to .0001", maybe +/-.0001"

 

dude, please get an american one, or at least borrow someone else's if you don't wanna spend the money, we don't need more chinese junk here

 

A dial bore gauge is calibrated with a micrometer every time you use it.

 

Depending on what one you get, they're just fine for engine work. At work we use calipers to check stuff way more critical than engine parts. And yes, we use micrometers for the even more critical stuff but the calipers are used the most.

Edit: I should say, some calipers are fine to use when you're able to use them.

 

i wouldn't look at anything but starrett. like they say you get what you pay for and if you buy a cheap set you have cheap tools and they aren't cheap because they spend a lot of time making them.

 

Calipers are fine for engine work, if you know how to use them and are careful, and get a good one. The better ones are accurate and repeatable to .0005" (half of a thousandth), which is all you need.

Like ede said, Starrett is a top of the line brand. Mitutoyo, Brown & Sharpe, and Fowler are also good, although Fowler sells some super-cheap ones that are pretty weenie.

Stay away from stuff like Harbor Freight and the like. Precision costs money. If it sounds like the deal is too good to be true, then it is. Expect to pay $100-150 for a quality product.

www.mcmaster.com
www.use-enco.com

 

Calipers rule of thumb, +/- .002" accuracy

Just yesterday I tested calipers in a humid 82 degree enviroment vs. ones in a climate controlled enviroment, they deviated just over .002" on the same gage block.

When you have .002" clearance on the crankshaft/bearing, the accuracy of the measuring device should be .0002" (which a mic can acheive better then calipers).
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Yeah, a dial bore gage just uses the mic as a reference (zero is nominal, and any deviations from zero are to be added/subtracted from whatever you set the mic to).