Lube for the Plunge Indicator?

EmilioG said:
If the hairspring is gummed up or damaged, you'll need to send it in to Starrett. These old back plunger indicators are very hard to work on.
With what Starrett charges for repair, you may want to consider a new Mitutoyo back plunger. Much better and parts are available.
According to Starrett's repair guide, you have to make a special tool to work on these. Oil is generally not a good thing for indicators since they can ruin the delicate hairspring. Special watch oil is used mainly on the jeweled bearings only.
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That's what I was afraid of sending it off for repairs.
 
I operate a CNC vertical lathe at my job... this particular lathe is always pouring way oil out of the covers over the cross slide above the table. As a result, anything that gets used on this machine gets drenched in oil...

I have an Interapid indicator that I use to indicate parts on the machine. Several years ago, there was a time when I literally had 1/4 inch of way oil standing inside the face of my indicator.

It was due for its yearly calibration check, so I wrapped it up and sent it to our calibration department, knowing that they would clean the oil out of it before calibration.

When I got it back, there was a note on it: PLEASE DO NOT EVER OIL YOUR INDICATOR... EVER!!!

The next year, when I sent it to them again, I included a note that read: Please change the oil in this indicator while you have it... thanks!

-Bear
 
Funny, I just fixed my Starrett 196 back plunger last week. It was sticking and moving very slow.
To gain access to it's workings you go in thru the face. Pry the outer ring off. Remove the lense. Pry off the pointer. Push four detents out of the way to remove the face. Everything inside is all metal, so you can clean it with whatever you want to. I was a little surprised to see how it works. The shaft that the needle is on is has a spiral shaped groove that runs along its length. The plunger moves up and down right next to it and has a rod that rides in the spiral shaped groove making it turn to move the needle.
After I cleaned mine, I lightly oiled everything and could not get it to work smoothly. I cleaned it again and this time I used powdered graphite on every moving part. This got my 196 working acceptably, but not perfect. I don't think the 196 could ever work as smooth a dial indicator. The only thing that you have to pay attention to is the position of the needle before you pop it off. I would give this a difficulty level of 5 out of 10. It is well worth doing.
 
Fantastic,glad to hear that you were able to make it better than what it was which is what I'm after.Mine I think the problem due to it just setting for so long and not being used.I did watch couple Youtubes of these back plunge types being clean and put back together.It look like they were using maybe a small rod(?) to put a drop of oil on then drop it on the jewel and that was about it.It look like the guys did this for a living they had all the right tools but wanted to see how get them apart.Which you provided the answer so that be a project for me when its nice and quite at home,be long wait:)
 
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