identity of this micrometers and restoration

[Anko]

hi to all

i hope some of your guys can helpme on this:

just about a hour I acquired two micrometers, i bought them because i believe that they are Mitutoyos micrometers, any way i got the smaller (0-25) for +/- US$ 8 and the bigger (50-75) for $10 8), they are used condition, very dusty and a with little of rust.

the lettering of the brand are lost because of the previous use

besides of that, they are in very good shape, sliding smoothly, just because of rust, long time no use or dust, rotating the thimble is a little tight... and if i want to rotate the thimble with the rachet, is has to be very slow, in other way the rachet star to doing clack clack clack (i dont know how to describe that jaja but you catch me the idea)

this just happens with the bigger one, the smaller are fine

and now i want to ask for a hint for how to get this old micrometers in shape, need to disarm, clean, lubricate, and reassemble..

if they are mitutoyos for real, i don´t want to make some mistake in the process of rerestoration that can compromise the acuracy...

well, here are a picture:

here are a the reference:

still very happy with this couple, i realy like the old tooling and machine, just like the old valve amplifiers and radios. ;D


thanks in advance

Saludos!

 

[Jasonb]

Just a thought on the big one as it seems the locking lever is broken is it in the locked position and therefore hard to turn?

J

 

[Anko]

nopes is not the locking lever, i remobe the screw and still is tight

but is no so extreme, just cant rotate the rachet fast

 

[Tin Falcon]

It is hard to say the Polish , Indian and Chinese factories have made many copies of name brand Micrometers. as long as it move smoothly and zeros out you are probably OK . It is hard to see from the photo but they appear to have carbide anvils so not likely significant wear on the anvil faces. I own some starrett and Brown and Sharp they are fantastic but the polish and Chinese stuff work as well. sometimes the makers name is engraved on the thimble as well as marked on the frame.
Tin

 

[Blogwitch]

If you are about to give them a clean and 'restoration', there is not a lot that can go wrong.

Just make sure you use no force on anything to get things apart or back together. It is just a matter of taking apart in a clean area, cleaning of the parts, a tiny drop of watch oil on all moving parts, then putting it back together in reverse order. You might have to adjust the tension ring around the main thread inside so that your thimble end ratchet works as it should (consistent readings when zeroed) without any backlash on the main thread.

Did the larger one come with a setting block, or a micrometer spanner with either? If not, you will have trouble doing the final calibrations after clean up.

I have Mitutoyo, Moore and Wright, plus loads of others that have come my way over the years, plus I have bought cheap Chinese sets, for use directly on my machines, and have yet to find any difference in their measuring capabilities, the only major difference being the 'feel', where the more expensive ones move a little smoother.


Bogs

 

[Anko]

i have cleaned the mics, the thimble problem just need a little oil, now the sliding is smooth 8)

I have doing some measuring with my chinese 1-2-3 block, and the two are working great, the 50-75 one was already calibrated, measure in the 2" side of the block 50.8 mm +/-0.002 mm far as I can see, depending on what of the four sides I measure, and in the 3" side the read is 76.2 mm (out of range but has the scale up to 76 mm) with some +/-0.003 depending on the sides

has for the little one, reads the 1-2-3 block with the same acuracy has the bigger micrometer, but has a 0.01 mm of disagree with my chinese 0-25 micrometer (that micrometer has the faces of the anvil and spindle out of parallels (i can see it looking the micrometer against a light)) and read my 25 mm setting block (that came with my chinese 25-50 mic) some close of 24.997 or .998 (far as I can see), and with that... all my micrometers are in conflict jaja

if can be worse, i really know that im using a cheap 1-2-3 block that came with a 0.0003" of error in the parallelism (that said in the calalog) ;D

in the lack of a calibrating block or gauge or some like that, i will just take the 0-25 mic as the absolute measure (because i can calibrate in 0) with that I will set the 25-50, and with that finally set the 50-75 all in funtion of the 0-25 mic

sow, very interesting how 0.002 mm can make me scratch my head jaja :big:


well, i have done some research to determinate if my new mics are mitutoyo or just a chinese fake, the spinde is shiny clear, just ultra small point of rust and just a few

also the two have a identification number scratched on the thimble, so i thing that these two come for some shop or manufacture... if the shop or factory was taking things seriously, then you might really be Mitutoyos

but no more illusions, i put the catalog on mitutoyo website and found the mics with the specs, I take the dimentions and compare it to the catalog, in overal almost was close with some 1mm max of error, then compare their weights with a weight cooking, the smaller read +/- 160g and in the catalog said 175g, the bigger read +/- 260, the catalog said 315g

i noticed in the 0-25 mm one, that in the back of the locking lever has a number two.

i googled some images to comparate, but still I can not check is are mitutoyo, all seems right at this point.

well, I will put some closer photos, if there are a fake, producers will try to copy the appearance, but not the smaller mechanicals pieces and detail, so that all I could disassemble them and take pictures, with the hope that some user has the same micrometer and can check if they match or not

the 0-25 :

the 50-75 :

??? ??? ???

Thanks in avdance

Saludos!!

 

[Anko]

Im still playing with the mics jaja ;D

in the 50-75 i have found what seems to be a serial number in the plastic grip, 931437 said

then i search on the mitutoyo website a way to send this number to a support mail so they could verify..

but get very confused on all the diferents kind of support they offer..repairs, capacitation, littérature calibration etc...

just cant find a way

for the de 0-25 no number yet found, but im impressed because if i took the 0 reading wit the mic in cold and then comparate it with the reading after hold it in my hand for 30 seg there is a diference (yet is just little, but i can see it!)


anyway i was thinking of using new bearings OD as a setting block, because i lack of a reliable setting block to calibrate my stuff

what do you think abut that? i can trust on the precision of the bearings OD??? ???


Saludos!