Lube for the Plunge Indicator?

[Kroll]

Guys I have a Starrett indicator that hasn't been used I guess over 30yrs maybe.I got this from the father inlaw after his passing and I dont think he's used it maybe another 10 plus yrs.He used it to align pumps with motors so knowing him it was never abused.The other day while dialing in my vise I think it may have been hanging up little.I would take my finger and using the mushroom pad I would kinda push in on it then let it go back into place.I did this couple times and got different reading up against the jaw of the vise.So knowing how long its been setting up maybe its sticking,is it possible to help this using an oil/lube?Just rubbing a light coat of the shaft of the plunger,is there something else that can be done to help this old tool thats been setting?The pic here is not the indicator but just like the one I have,just help me explain since I don't know the correct terminology.

 

[T Bredehoft]

Best Bet, sent it to Starrett, or Long Island Indicator for repair.

 

[benmychree]

You do not lube indicators, doing that will make them stick, it probably just needs cleaning to remove oil and dirt.

 

[Technical Ted]

I've successfully used mineral spirits to clean the shafts/stems on both dial and test indicators. Don't submerge it... just use a small paint brush or Q tip and apply some to the exposed shafts. Wipe off the excess after working it the movement back and forth a few times. Do it a couple times if you need to. This has done wonders for me in the past!

Do not use oil or other lubricant.

Ted

 

[benmychree]

I used to use trichlor for that, can't get it here any more ---

 

[bill stupak]

Naptha works really well for indicators, it cleans and I read somewhere it leaves a fine lubricating film after it dries. That's one of the reasons it is not good for paint prep. I've been using it for years. Stu

 

[benmychree]

Is naptha the same as lighter fluid?

 

[bill stupak]

Is naptha the same as lighter fluid?

Yes

 

[Ulma Doctor]

i have successfully used isopropyl(rubbing) alcohol to clean indicators of gunk

 

[EmilioG]

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.