Fixing my Chinese dial indicator

[MikeKParticipant @mikek40713]

So there was more damage to my dial indicator than I first noticed…caused by my caveman antics in trying to remove the bezel with a 24″ prybar (no joke, I actually did that).  Anyway, I was determined to undo my mess.

One of the mounts tore out and I fixed that with a brass plug soldered in, machined, filed, sanded, etc.

The aluminum bezel got slightly torn.  I hammered it to a reasonable facsimile, but am concerned that it will lift and jam in use.  Any thoughts on filing this?  If it was brass I could solder, but it’s AL.  Can I expect epoxy to have a good finish as well as not peel away at only a few thou thickness?

Also, I decided to remove the plunger for cleaning it and its bore, but can’t figure out how to remove the pin.  My screwdriver strains and risks breaking as the “screw”, if it is that, doesn’t move.  It might be pressed in and the screwdriver slot is just for alignment?

Mike

[HopperParticipant @hopper]

Looks like it is a pin pressed in there, from the larger diameter at the other end from the slot. Slot may well be where the end of the pin has been staked, ie hit with a chisel-edged tool to expand that end into what looks like a taper in the mouth of the hole.

I would leave it as is and just soak the whole thing in solvent (petrol works well) for a day or two and move the plunger in and out a bit to clear any debris. Dont lube the plunger or mechanism with machine oil that can go gummy over time. Mitutoyo recommend nothing other than a drop or two of petrol to lubricate the plunger if it becomes sticky in use. But maybe that was in the days of leaded petrol? Perhaps a drop of clock oil?

[Grindstone CowboyParticipant @grindstonecowboy]

I’ve found lighter fluid works well, just oily enough – the cheaper, pound shop versions are oilier than name-brand stuff, so don’t go too cheap.

Rob

[MikeKParticipant @mikek40713]

I’d prefer to disassemble, but okay…I’ll just soak it and not break anything else.

Any thoughts on repairing the torn aluminium ring?

[bernard towersParticipant @bernardtowers37738]

My Chinese Dti packed up and it was the plastic part that the crosspin on the mainshaft slides along just disintegrated so a little milling exercise on some nice engineering plastic and it was better than new (honestly)!. I use it on a mag strip on the toolpost for truing things so back in business.

[old martParticipant @oldmart]

If the slotted end looks like a grubscrew when viewed with a magnifier, you might try screwing it in as the other end looks larger.

However, the cleaning with petrol or lighter fluid would get the plunger just as clean without removing it from the body. I restored a Baty which looked like it had been attached to a pub ceiling for 20 years in the days when smoking was legal. I used solvents and left the plunger in place and 40 years later it is still smooth running. Poor thing hardly ever gets used, I prefer the lever type used for centralising work in lathe chucks and checking squareness when milling.

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