Cleaning Dial Indicators

The Mahr's can be a PITA the first time, everything has to be just right to get the roller in the correct position to get it back together.

I R&R all kinds of gauges every week, I have a few indicators on my bench tonight. After disassembly I clean the parts in an ultrasonic parts cleaner with either Branson cleaning solution or a Dawn dish soap solution in it. I never lubricate the inner workings.

Do you think you could shoot a little video showing how you do it? I'd be lost if I took it apart and couldn't get it back together. It's DODGE branded, made for ignition work on diesel engines. (I think)
 
Not sure what you mean by "how you do it". If you mean repairing an indicator, they are all a little different. I only make videos of my hobbies, gauge repair isn't one of those. Fixing them isn't hard at all but can be intimidating the first time. If you don't have access to replacement/repair parts it's kind of senseless to crack them open unless you're sure they're just grimy inside. I repair several a week in a manufacturing plant that machines cast iron on 20 machine lines and I've yet to find one that's dirty inside the case. Most of the "cleaning" needed to loosen up a shaft consists of squirting isopropyl alcohol on the joint/shafts to flush the grit out. Most repairs result from the gauge being dropped and involve replacing one or more gears or just resetting the mainspring tension. Every gauge that I repair is also calibrated afterwards on an Indi-check.

Indicators are instruments that don't come lubed from the factory. Oil attracts dirt and collects it exactly where you don't want it.
 
Indicator internals should be treated like mechanical watches. They have jeweled bearing surfaces that are lubed with specific weight oils not just any oil.

Naphtha, lighter fluid, is a very common cleaning solution. Complete disassembly, cleaning of parts, and using peg wood to clean jewels is the proper manner for service followed by the proper lubrication and assembly.

Excess application of oil will attract unwanted dirt and cause issues. The amount of oil applied is very small but without it the parts will wear and reduce the service life.

Keep in mind that this is only for dirty gummed up works. A true watch repair shop charges in the neighborhood of $100 to clean, lube, and test most basic mechanical watches. Indicators are much simpler, one might be able to get one serviced for a better price.
 
Thanks Terry. Your link is the correct one. Perhaps the mods can fix my link so no one goes on a wild goose chase.

Darrell
 
Be careful using aerosol cleaners like Brake Clean, they work but too much will distort plastic and remove the numbers and marks from the face.
Ask me how I know...
 
Well I just sent my indicator repair guy 10 calipers, three 3d tasters, and an bunch of other misc indicators that I pulled out of the scrap bin. Hopefully I can use it for trading to get 2 DTI's fixed along with some other items I sent him. I just shake too bad to take small things apart. Tim
 
Hello, i have an USSR made 0.01mm/0.0005" 12.4mm/0.5" range dial indicator and it was sticky. I decided to part it of because i didnt like to use it since it is not reliable. Biggest problem was removing pointers (1st for 0.01mm 2nd for 0-1 mm ) they were glued not hard pressed. Anyway i just washed all parts with %99 pure isopropyl alcohol. It removes dirts perfectly. Used tooth picks to clean holes. Reassembling was a bit stressed job but managed it anyway and it is working nice and smooth after all. I noticed that plunger has a spring, tension can be adjusted by remeshing rack-pinion but there is another worm spring in mine, it should be adjusted also which has key role on pointer returning to 0.
I wouldn't use any kind of lubricant. All critical parts usually has 'jewelled' beds. Any kind of lub tends to get dirts anyway. Since mine is Soviet made lol it should be work for another 20 years with this condition.
Actually i watched metal tips and tricks related video (which he doesnt suggest to do) and whole process took about 45 min at all. 0.01mm dial indicator is not hard as it seems but i would not mess with 0.002mm/0.0001" dial indicator which i dont have mechanical one, because as far as i know spring pressure is very important for them.
 
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