External micrometer sets

[englishmaninwales]

Engineers please! Looking to treat myself to a set of external micrometers for occasional use in engine rebuilding checks. To cover the range of sizes I’ll need a set of 4 in the range 0 - 100 mm
Which make should I be looking at and which to avoid, choice is worryingly large and some are cheap and nasty!
Thanks
Malcolm

[rgh0]

Mitutoyo is my preferred manufacturer of precision measurement tools. Not cheap but will last a life time. A huge range of sets to choose from and I always by mm sets and prefer mechanical rather than electronic read outs as just as accurate and you dont have to keep turning them on If you search the internet you will often find them second hand in good condition for a fraction of new price

cheers
Rohan

[lotusfan]

Hi Malcolm

I agree with everything Rohan says. I would add Starrett and Moore and Wright as acceptable manufacturers. Internal micrometers or hole gauges or telescopic gauges are also useful.

e-bay is a good source of second hand tools but not cheapo new!!

[661]

I bought a Sealey micrometer and it was clearly giving different readings for the same measurement.
I then bought a Mitutoyo and it measures the same, exactly, each time.
Yes they are more expensive. Buy cheap, buy twice.

[2cams70]

If you want some hidden gems buy some used ones made by NSK. NSK no longer make micrometers but when they did they every bit as good as Mitutoyo and can be bought now often at a fraction of the price of Mitutoyo. Sometimes they were the supplier behind house brands such as "Draper". Key thing to look out for is "Made in Japan".

[Craven]

Don’t buy cheap, quality second hand sets are around especially if you stay with imperial sizes as are our cars. Make sure the set still contains all the calibration slips or they are useless, big disadvantage with large size micrometers.

[snowyelan]

Hi All,

Quality second hand over cheap new.
I have found the recent quality of starrett has dropped off significantly. My co-workers won't buy them anymore. Starrett pre-2005 ish is top notch though.
One thing I am a fan of is having a gauge block set to reference. Most mics come with one reference block for setting. Gauge blocks allow you to compare the measured dimension to a known good dimension you can generate from the stack of blocks. More apples to apples in my opinion as you're just looking for the mic to read the same for the Gauge block stack and the part you are measuring.


https://en.wikipedia.org/wiki/Gauge_block

[Elan45]

I'll buy used Starrett any time and agree w/ another's comment about our cars being Imperial, so why not have Imperial sized tools. I was not aware of a decline in Starrett quality, but maybe because I typically buy used if I can.
Brown & Sharp was always my 2nd choice, but I have some good Japanese, British and German tools too.

I also try to stay away from battery operated tools because I don't use many of my tools daily, so when I need it, the digital tool usually needs the battery replaced.

RL

[englishmaninwales]

Thanks for the good advice, as always, on Lotuselan.Net
Malcolm

[promotor]

If you are buying micrometers to work on old English vehicles (and anything American) I would advise not to buy in the range you mentioned of 0-100mm. In my experience you should use Imperial mic's as the engines were designed in Imperial measurements and manuals will therefore be in Imperial. Converting figures is distracting and mistakes can occur.

As has already been mentioned most old quality micrometers are likely to still be as accurate as they were when new and are therefore better value for money as they don't sell at new prices.

Ideally you want one that measures in graduations down to 0.0001" (tenths of a thou) - that means that not only does the thimble carry a 0.001" (thou) figure to read off but the barrel then gives a measurement that splits each 0.001" figure into a 0.0001" reading. Without the 0.0001" figure you can guess an approximate figure between each 0.001" reading but it's better to have it on there and know for sure.

It's nice to have a clutch on a mic but some people won't use them as they like to "feel" the figure. I think it's better to have the option. Most mic's should have the clutch but sometimes they are removed for whatever reason in used items.

A while ago I bought a new 2"-3" micrometer from Cromwell Tools branded as Kennedy - this has the 0.0001" graduation on it and I think it's as good as any of the brands mentioned above as it is extremely repeatable in its readings. It was priced well but they seem to have crept up in price in the last 5 years.

I own at least one of each brand below and am happy with all :

Mitutoyo
Moore and Wright
Starrett
Shardlow / GKN

[englishmaninwales]

Thanks, that makes good sense.
I should have been clearer in my original post, I’m choosing mm as 2 of my 3 Caterham engines are sitting in packing cases telling me to pull my finger out during these lockdown periods and get them rebuilt! They are various versions of the K Series, so all the specs are mm.
My Elan engine was rebuilt for me 3-4 years ago, and is in good health, so I’m hoping I won’t need to look inside that for a while (dangerous statement, touches wood!).
I asked on this forum because I respect the opinions on here!
Malcolm

[661]

These guys are reliable
https://gandmtools.co.uk/?product_cat=metrology

[rgh0]

All the measurements in the Lotus Manuals are shown in both mm and inches. I do all my measuring and thinking in mm which I find easier to do thus I use mm measuring tools. You will also find that many of the dimensions are also actually in mm increments ( e.g. bore sizes !)

50 years ago Australia did a full change to using metric units on everything unlike the US and UK so I guess its more natural here now to think in mm. Because people in US and UK prefer inches you find second hand mm sets cheap and virtually unused from those countries

cheers
Rohan