Mitotoyo dial caliper battery or innards.

[Clive FarrarParticipant @clivefarrar90441]

I have a treasured Mitotoyo digital caliper. You know theone you go to despite having 4 others.

Just recently no matter what battery ( LR44 / AG13 ) I put in it it starts to flicker between zero and minus value random numbers up to the 500’s, impressive on a 150 mm caliper.

Do you think it is just naff battery’s ( up to a year old ) or is it the internals going haywire and I need to peacefully retire it.

 

Any suggestions as to how I might revive it would be greatfully received . Thank you

 

Clive

[mgnbukParticipant @mgnbuk]

Have you tried cleaning the cover strip glued over the sensor area of the main frame with something like IPA. Surprising how grubby this gets with use & this can affect the operation of the measuring system.

Used to get a lot of digital caliper issues when I was working- made worse by the company exclusively machining graphite so the cover strip get very grubby. 9 times out of 10 a fresh battery, a good clean and adjustment of the wear adjustment screws on the moving jaw got them going again & repeatable measurements on slip gauges.

Is the LR44 the correct battery spec. recommended by Mitutoyo ?

I have a digital micrometer that won’t work with LR44s & requires SR44s. LRs are alkaline, SRs are silver oxide. Stopped buying “generic” or branded LR44s and only buy Renata brand SR44s now. Cost a bit more, but work reliably for longer.

Nigel B.

[Howard LewisParticipant @howardlewis46836]

It might be worth stripping off the read head and cleaning both the scales on the body, and within the read head.

Sometimes this works with just a clean dry cloth; other times the cloth needs to damp with white spirit.

Let us know how you get on!

Howard

[bernard towersParticipant @bernardtowers37738]

Agree with the above adding in , short the battery conn for 5 or ten secs that some times resetsc it.

[JAParticipant @ja]

My Mitutoyo digit calipers died within this last month and I replaced the SR44 batteries with LR44s. All it did was to flash its display at me. The Mitutoyo literature says that LR44s will not work in their calipers. They need SR44s.

The LR44 cell output decays with use while SR44 does not, it just suddenly stops. They are made for power sensitive devices. The real problem is that the local corner shop or supermarket does not stock SR44s. I have added them to a future RS order. The Mitutoyo calipers are office based while the workshop ones are TESA (better but much older than the Mitutoyo).

JA

[PeteParticipant @pete41194]

Almost all of my Mitutoyo digital tools use the SR 44 batteries, while they do specify to use those, the LR’s will also work because I can’t always get the SR’s where I live. However there’s no comparison between the two for battery life. Easily 2-3 times longer for those SR’s. Unfortunately defective coin cell batteries can sometimes leak. I’d first remove the cover and battery, then check the bent sheet metal contacts for any signs of that. Or if the tool has been roughly treated, the battery contacts might have been bent down a bit too far and aren’t providing the proper contact. Some GENTLE prying to move those contacts up a bit might be needed?

I’ve read a few other forum posts mentioning it, if there’s the slightest sign of any corrosion on those contacts, then some very fine sand paper glued onto the end of a rod that will fit inside the recess may remove it. Then flush it clean with mgnbuk’s thought about IPA or a proper electrical contact cleaner. But I’ve also read posts where the battery leaking wasn’t discovered for a long time and the whole display assembly had to be replaced.

Without knowing how to read the lot codes on the battery packages, I can’t think of any way to be sure how old any new battery might be since it was manufactured, and obviously they will self discharge even when not being used. A non SR battery may still have power, but possibly not enough to operate the display. If I was in doubt, I’d just try a new SR battery.

[HollowpointParticipant @hollowpoint]

One of the things I have noticed about alkaline batteries is that they occasionally leak vapour. In something small and enclosed (sealed against coolant) like a caliper, the vapour can fill the housing and corrode the electrical components. I’ve seen this happen a couple of times, both times in mitutoyo micrometers incidentally.

[egaParticipant @ega]

Is it possible to amend the title of this thread for the benefit of posterity, please?

[Hollowpoint]

On Hollowpoint Said:

One of the things I have noticed about alkaline batteries is that they occasionally leak vapour. In something small and enclosed (sealed against coolant) like a caliper, the vapour can fill the housing and corrode the electrical components. I’ve seen this happen a couple of times, both times in mitutoyo micrometers incidentally.

Could this be the result of using cheap, low or unbranded, batteries?

JA

[jaCK HobsonParticipant @jackhobson50760]

My experience is that really cheap batteries might not last a year even unused. Go to be worth trying a brand new one before any other fault finding.

[Peter Cook 6Participant @petercook6]

For the OP’s problem, I would go with Howard (and Bernard)’s suggestion. You have probably got a bit of metallic dirt between the read head and the slider.

For several years I used the guts of an old set of callipers (albeit not Mitutoyo) as a DRO on the cross slide of my little lathe. On several occasions I got exactly the symptoms described. Removing the device, opening up the read head and cleaning it and the slider with IPA always resolved the problem.

[Author]

Posts