Cleaning dial gauges

AndyN wrote:
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Thanks for that; I have a s/h Mercer G.303 dial indicator,
http://www.cromwell.co.uk/MER3003187V (which I used here:
http://www.geocities.com/plybench/flatten_practice.html#measure
)
But it's a little sticky. Despite my simple diagram on the website, I *actually* did the measurement by sloping the plane slightly, first "nose up" then "nose down", and tracking the dial gauge in both directions to minimise sticky hysteresis errors.
I didn't want to go into all that on a "simple" website.
But now I think I may have a look inside the dial indicator.
Wish me luck!
BugBear

snipped-for-privacy@btconnect.com Wrote: > On 25 Mar, 18:01, "AndyN"
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Hi Tim, If you must ultrasonic them, might I suggest you remove the face first. The "paint" surface is often dry and crumbly and will not stand much abuse. Ned Ludd

snipped-for-privacy@gmail.com Wrote: > I've just obtained two dial gauges as part of a job lot, they're
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Hi Tim, DTIs are quite fun to pull apart and repair. No special tools are needed save watchmakers screwdrivers tweezers and a means of pulling off the pointer. If you go to one of the Watch and Clock fairs, you should be able to get the bits and pieces including a glass., you will need to know the size first. Failing W&C fair Fleabay must have something. Re. cleaning, were not talking Rolex so lint free rag or tissues and a solvent will work wonders, but no oil please. Although watch oil on internal pivots should do little harm, if correctly applied ie V little. Ned Ludd

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What is the trick to moving the glass from dial gauges? I have nice Mitutoyo imperial dial gauge which has a slightly bent needle. I would love to straighten it, but I can't see how to remove the front bezel and glass.
Mike

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What is the trick to moving the glass from dial gauges? I have nice Mitutoyo imperial dial gauge which has a slightly bent needle. I would love to straighten it, but I can't see how to remove the front bezel and glass.
Mike
Hi Mike, Had a look through my collection of DTIs but no Mitutoyo. There semms to be a wide choice of assembly methods amongst (British) makers, from circlips to screws from the back to screws from the side. If Mitutoyo dial calipers are anything to go by, the bezel and glass have to be levered off as one. Ned Ludd

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Success! I removed the case back, and eventually spotted two tiny spring wire clips which locate in an internal groove in the bezel to retain it.A bit of fiddling with some fine tweezers to hold one of the clips back, and a fine blade under the edge of the bezel, and off it popped. Replacement is easy (compared to removal).
Mike

An excellent solvent for this sort of thing, reasonably cheap and easily obtainable, is Colman Fuel. Essentially pure naphtha, it dissolves oils and evaporates completely.
John