Calibrating Micrometers

.

So I wrote to them, and received an exemplary personal response from Raymond W. Marquis, Quality Assurance Manager

He attached a three page document which outlines their inspection process

... It should be available to view in my Dropbox : **LINK**

MichaelG.

Posted by SillyOldDuffer 13/11/2020 10:26:39

If only high-end measuring was affordable...

I don't suppose that high-end measuring will ever be affordable
but low end is these days ,i bought a set of these micrometers
from J& L Value brand so probably not as good as Mitutoyo,
however supplied with setting standards they read though the range
to the line at both ends and are very well made.At the time i bought
these the average price of these about 4 years ago including the
VAT and delivery was just £13.50 each.
They still sell these in the Advantage flyer in sets of 3,4 ,6 and 12 the
average price still is as low as £15 each.

Buying old kit these days is a no brainer and as one poster indicated
there is a gauge checking set from Chronos but at a £148.74
to me that would seem to be expensive and a bit pointless just to see if they were
any good.

John

Good morning,

Thank you for the ongoing suggestions. I realise that lower end products are not expensive new; I have new lower end metric DTIs, micrometer and finger gauges with which I am happy. However, the micrometer is only up to 25mm; too small for the car work. The set of four second-hand Moore and Wright devices cost £10.00 compared with at least £60.00 for new, so were worth a punt for what will be very occasional use.

Unbeknownst to me, an friend has a set of imperial setting blocks which I can borrow, so I shall at least be able to assess their basic accuracy. Once lock-down is over, I shall be able to find out whether I have bought a bargain or a pig in a poke.

Regards,

Jamie.

Well done with your £10 set James - sounds like a bargain.

Many good quality second-hand Mics have had little heavy use and can often be had for little more than the cost of postage if you watch out for them. The 'part' that is usually in very poor condition is the case. It's also not really possible to check/examine the anvils on eBay (so some risk there) but all of my purchases have been fine in this respect.

Normally a strip down, careful clean and re-oiling (with a very thin instrument oil) will give you an instrument perfectly usable in the home workshop. If the paintwork is a bit worn or battered - then it can be easily stripped off and resprayed.

Regards,

IanT

Edited By IanT on 14/11/2020 11:35:27

A quick update. I borrowed a set of imperial setting gauges and was pleased to find that the micrometers are accurate and that the anvils are all parallel.

Regards,

James.

       It would be worth investing in a box of secondhand slip gauges, they have multiple uses, not just for calibrating micrometers.

I bought this 0-150mm micrometer when it came up on ebay, to replace the 0-4" which was stolen from me some years ago. It came with a full set of length bars and the photos show the heat plate that Rod printed to fit it.

Edited By old mart on 01/01/2021 15:44:29

Edited By old mart on 01/01/2021 15:46:57

Edited By old mart on 01/01/2021 15:47:33