Comparing Gage Block Sets

I'm in the market for a gage block set that I plan to use to calibrate my measuring tools and use as a calibrated shop reference. Therefore I'm only considering NIST traceable so I know my masters are verified against a universal standard. I'm looking at the SHARS grade AS-0 SKU: 303-5307C set that is NIST traceable with serial numbers. It's specs are 5µ (0.05-0.4"), 6µ (0.45-1"), 8µ (2"), 10µ (3"), 12µ (4").

At $415 I'm skeptical since the equivalent grade 0 Mitutoyo or Starrett are around $1600. However it does state they are measured according to ASME B89.1.9-2002 and each block is serialized and the deviation from the NIST traceable size is recorded.

Does anyone have any experience having a set like this independently qualified and verified their stated accuracy isn't bogus? Am I wasting my time/money even considering something that is this cheap? Is there another brand I should be considering?

There is a Starrett Grade B 81 piece set for only 500, but the grade B specs aren't tight enough tolerance for what I want. Edit: I also just noticed the Starrett grade B are imported anyway.

I think the marking is very important so the numbers are most clear to see. That makes building a set and putting them back much easier. I have seen/used some sets that are a bugger to work with for this reason.

I have Mitutoyo 1", 2" and 3" blocks that are used ONLY for calibration. That gets all my mics and calipers to 6".
I send them out to be certified every 3 yrs.

I don't think you need an entire set.

Do these shars sets have light lasering that fades with use? Or are they just small and hard to read?

re: I have Mitutoyo 1", 2" and 3" blocks that are used ONLY for calibration. That gets all my mics and calipers to 6".

If you only measure a micrometer at one place (like 1") you are not checking for worn spots or "drunken" threads.

Lucaselef said:

I'm in the market for a gage block set that I plan to use to calibrate my measuring tools and use as a calibrated shop reference. Therefore I'm only considering NIST traceable so I know my masters are verified against a universal standard. I'm looking at the SHARS grade AS-0 SKU: 303-5307C set that is NIST traceable with serial numbers. It's specs are 5µ (0.05-0.4"), 6µ (0.45-1"), 8µ (2"), 10µ (3"), 12µ (4").

At $415 I'm skeptical since the equivalent grade 0 Mitutoyo or Starrett are around $1600. However it does state they are measured according to ASME B89.1.9-2002 and each block is serialized and the deviation from the NIST traceable size is recorded.

Does anyone have any experience having a set like this independently qualified and verified their stated accuracy isn't bogus? Am I wasting my time/money even considering something that is this cheap? Is there another brand I should be considering?

There is a Starrett Grade B 81 piece set for only 500, but the grade B specs aren't tight enough tolerance for what I want. Edit: I also just noticed the Starrett grade B are imported anyway.

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If you are looking at Shars, may as well consider these. Marked and serialized AND probably made by the same peoples that make all the off brand and elcheapo (skars) stuff anyways.

https://www.amazon.com/Accusize-Ste...ywords=gauge+block+sets&qid=1614794337&sr=8-3

greif1 said:

re: I have Mitutoyo 1", 2" and 3" blocks that are used ONLY for calibration. That gets all my mics and calipers to 6".

If you only measure a micrometer at one place (like 1") you are not checking for worn spots or "drunken" threads.

Click to expand...

How many spots should I be checking?

Lucaselef said:

Do these shars sets have light lasering that fades with use? Or are they just small and hard to read?

Click to expand...

Likely you will have your set for a long time so good to investigate that feature.

I don't think Shars and precision metrology belong in the same sentence. I also tend to not have faith in any traceability claimed.
Money spent on quality is rarely regretted and if you're on a tight budget, there are lightly used, quality sets on eBay that can be had for similar money.
My opinion only of course.

Mike1974 said:

If you are looking at Shars, may as well consider these. Marked and serialized AND probably made by the same peoples that make all the off brand and elcheapo (skars) stuff anyways.

https://www.amazon.com/Accusize-Ste...ywords=gauge+block+sets&qid=1614794337&sr=8-3

Click to expand...

Those sets are not checked against a NIST standard. Someone asked that in the questions section. That makes the Shars a better set. Also shars is selling the grade 0 on ebay for $270 which is unfathomably cheap.
SHARS RECTANGULAR GAGE BLOCK SET 81 PC .05-4" AS-0 GRADE W/ NIST CERTIFICATE L} | eBay

CPM2014 said:

I don't think Shars and precision metrology belong in the same sentence. I also tend to not have faith in any traceability claimed.
Money spent on quality is rarely regretted and if you're on a tight budget, there are lightly used, quality sets on eBay that can be had for similar money.
My opinion only of course.

Click to expand...

I'm almost more leary about buying a used set than i am quality import. There's no telling what sort of abuse they might have been subjected too over the years. Unless i knew the history of them, i'd prefer to buy new with recent qualification (however valuable that is)

CPM2014 said:

I don't think Shars and precision metrology belong in the same sentence. I also tend to not have faith in any traceability claimed.
Money spent on quality is rarely regretted and if you're on a tight budget, there are lightly used, quality sets on eBay that can be had for similar money.
My opinion only of course.

Click to expand...

I'm of the same thinking. Even with a valid NIST traceable cert, how long will an import set stay in size? Not only use wear but changes due to the steel aging. My thought are to use the imports for setup and layout but not product acceptance.

Lucaselef said:

Those sets are not checked against a NIST standard. Someone asked that in the questions section. That makes the Shars a better set. Also shars is selling the grade 0 on ebay for $270 which is unfathomably cheap.
SHARS RECTANGULAR GAGE BLOCK SET 81 PC .05-4" AS-0 GRADE W/ NIST CERTIFICATE L} | eBay

Click to expand...

Well it's your money. Not sure why you are so interested in the NIST inspection. Anyone can say it is (forge and/or fudge it), and if it is indeed going tobe used as a Master, it will need claibrated every 1-2-3 years or whatever your ISO/AS9100 (assuming that is what you are after) plan says, so....

Is your shop climate controlled (not just air temp, but humidity as well) enough that NIST or not is going to make a difference? I would venture most of us can't measure the millionths from nominal deviations on gage blocks anyways. I think those deviations are only helpful when making stacks and you want to know if it is actually what you want ie- you add/subtract all the numbers to get the "true" size of your stack.



https://www.mscdirect.com/product/details/59603878

Maybe I have gotten lucky over the years. I have purchase 3 or 4 Starrett sets off of eBay.
I think gage blocks are actually one of the easier things to visually determine amount of use through pics. Its at least easy to decipher which set have a lot of use/abuse. Also, if there are missing, or damaged pieces, they can be replaced fairly inexpensively.

Booze, Check out Mitutoyo America Corp. on YouTube. There are videos from their metrology lab, showing how to calibrate calipers and micrometers. Lots of other calibration info also.
Joe

Let's just say there's a whole lot of room for fudging those "certificates of accuracy and traceability" when it takes some fairly decent money to have them independently verified at an outside source. I've zero idea about those Shar's sets, but for whatever this is worth? About 12 years ago I bought what I now consider as my first set at a mid range price for steel gauge blocks from Penn tools in N.J. I specifically made a point of not going for a rock bottom bargain price simply because at those prices I sure didn't think they could be accurately made by anyone. That 82 pc grade 2 set set cost me just about $600 at the time. Generally they looked ok and came with a full sheet showing every blocks true deviation in millioth's, all signed off from the whoever "measured and inspected" them as being within the then grade 2 specifications. Except for one odd thing I found while cleaning off the slathered on fish grease? they used as an anti rust preservative. Two of the blocks were laser marked and measured with good digital mikes as the exact same size as close as I could measure. Penn Tools were great and sent me the correct replacement size except that one was made by Mitutoyo.

Ok mistakes can happen at any manufacturer's including the best, but one would assume every effort would be made to keep any gauge block set as a distinct and separate combination whenever that measurement and certification is going on. So for me that was an instant confidence reduction for what I bought right there. 4-5 years go by and I lucked out and bought a still factory sealed 82 pc set of Mitutoyo grade 2's for about $1200 on Ebay. That gave me a direct comparison between the first off shore set and what a decent gauge block really should be. I can truthfully say there's really no way to do that direct comparison between them. In every instance the Mits. have a far better surface finish and they noticeably wring together much much easier and tighter. That first off shore set are now my shop blocks and the Mit's are kept for calibration and when in matters. That first set was for me almost a waste of money. As they say, buy once cry once. Again that Shar's set might be just fine if your willing to pay verify they actually are. I doubt there's many who buy lower cost off shore gauge blocks and then immediately send them out for a proper high cost re-calibration check. My Taiwan built rotary table came with a certificate of accuracy as well. The numbers all look pretty good, except for anything I can easily check such as run out on it's MT spindle taper and table flatness didn't match what the factory wrote down. That also leaves it's worm and worm wheel "guaranteed" accuracy to low seconds level pretty suspect in my opinion despite what the factory inspector supposedly verified and signed off on. Just those two items taught me to never blindly trust anything, and that set of Mit blocks now allows me to double check most shop items I've bought since. So without that high confidence and trust in what your buying for gauge blocks you can't ever know anything there used for with 100% certainty.

Typically you check at 4 places which cause the spindle to be in 90 degree increments (to show drunken thread, and possibly show problems from worn anvils), plus near max travel which is most sensitive to showing linear error.

Is your shop climate controlled plus do you let a part stand for a half hour and wear your cotton gloves handling parts to be measured and measuring gear, common to gage work/making.

So how much does it commonly cost to get a set of Blocks calibrated/certified ?
It seems to me that this should be done to trust any used Set or Shars set.
If it matters anyway.
Larry S
Fort Wayne, IN

I too am interested in what it costs to get a set certified against a NIST standard. If a set claims to have tolerances of +-.000001 on a 1" block but the block actually measures .999000" when compared to NIST standard then it might as well have a +-.001" tolerance. Calibrating/certifying to an internal standard means absolutely nothing.

I'd the sharks set is actually NIST traceable, then it's a really good deal. However the fact that no other set within 3x the price makes the same claim makes it smell funny.

As for used sets, there's no telling how they were treated, they could have been stored in a shed with wild temperature/humidity fluctuations that sent them out of tolerance.