review of my three new dial calipers from Enco

When I use dial calipers, I maintain the same thumb pressure, clean the jaws, and zero often. I try to rock them into perpendicularity, and measure with the same spot on the jaws each time. I check my accuracy with pin gauges. I interpolate between the .001" hatch marks with my eyes. My eyes can easily resolve .0002", but .0001" is harder.

0) My 8 year old Midway $20 Chinese 6" calipers can be trusted to .0002" 1) My new Enco $14 Chinese 6" calipers can be trusted to .001" 2) My new SPI $25 Chinese 6" calipers can be trusted to .0025" 3) My new Mitutoyo $72 Brazilian 6" calipers can be trusted to .0002"

The thing of interest was the $25 SPI looks like it is the same as the $14, with nearly the same serial number sequence on the back. But the SPI costs more and are not as good. The "SPI" name has been w**re'd out to Chinese junk.

Reply to
Clark Magnuson
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--Maybe SPI should change their name to CPI, eh? :-)

Reply to
steamer

Your dreaming if you think a dial caliper can resolve .0002"

Reply to
Tony

He may be confusing resolution with accuracy.

Reply to
Dave Hinz

Drop a zero and get real.

Wes

Reply to
Wes

When my cousin designed the electronics and software for some digital calipers, he got a patent and did a great job. I got a pair. The .0001" column is only a half a digit. It either reads .0005 or .0000". I called him up and told him I wanted the extra resolution, because I know how to control calipers and use it. He says that management did not want the resolution displayed if the accuracy was not there.

Reply to
Clark Magnuson

A very skilled hand can repeatably measure to .0002" with a good dial caliper. I once knew a machinist who used ordinary inside calipers (not measuring tools, just adjustable feelers) to "feel" inside dimensions and transfer to a mike. He said he could reliably do .0002. I didn't believe him until he proved it. He really could!

He was at least 60.

The issue is in getting a consistent "feel". Dial and digital calipers have a lot more "spring" to them than a mike does.

I don't trust calipers in my hands to better than .0005 on a really good day, or much better than .002 most days.

Reply to
Don Foreman

I've seen older Starrett dial calipers read several random gauge block stacks to better than 1/4 thousandth up to 6". The Phase II one I brought in for cal was barely within 0.001" .

Jim Wilkins

Reply to
Jim Wilkins

Have you adjusted the gibs on all of the calipers?

Mark Rand RTFM

Reply to
Mark Rand

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