How to repair "tarnished" gauges

[old mart]

Engraved markings will benifit from rubbing with a very fine abrasive, electro etched marks will not.

[larry_g]

X2 on the Hoppes # 9 I've been using it for years. It removes the old brown lube and leaves a film of lube on the item. I use the White non-abrasive scotchbrite and a soft tooth brush.

Works for me

lg
no neat sig line

[Doozer]

Dave mentioned before that his indicator was a Zina.
I have seen them on ebay before.
His ATW lathe has a 2 speed back gear.
Great old lathe.

-D

[The Metal Butcher]

It's a strange looking beast. That dog leg in the needle almost suggests that it's supposed to rotate upward in an arc, but obviously it's constrained or held captive by the little wire running lengthwise over the scale.

Lynn, check out Old Steam Powered Machine Shop" on YouTube. Dave Richards. He uses that exact, or a very similar Starrett indicator on his 20" American lathe.

[Doozer]

Looks like a ZINA indicator gauge.

-D

[J Tiers]

That's an indicator, a "plunger" type (as opposed to a lever type). There were plans for those running around the (pro) machining mags a hundred and something years ago when indicators were not so common. If I was at home I could give a reference.

[SLK001]

It's blackening that is happening naturally. hydrochloric acid will remove it in a flash.

[lynnl]

It's a strange looking beast. That dog leg in the needle almost suggests that it's supposed to rotate upward in an arc, but obviously it's constrained or held captive by the little wire running lengthwise over the scale.

[JRouche]

JRouche, what's that thing-a-ma-jig is the rightmost position of your first picture?

Hey Lynnl I think it is a mechanical indicator. I forget where I got it or how to use it. JR

[lynnl]

JRouche, what's that thing-a-ma-jig is the rightmost position of your first picture?

[JRouche]

I might be thinking of something different then tarnish. Maybe varnish?

My stuff has what I considered tarnish but it is not rust, just caked on wd40 really. Otherwise it would be rusty.

Some pick of some gauges with varnish/tarnish. I put the dial indicators in there to show before I try Doozer's trick. I have to find my gun cleaning case now, havent shot in years and that is where the hoppes is. I usually use semichrome or brasso for plastic lens. JR



Some morse A-Z drill blanks nice and packed in their box.






A lil varnish sticky. Acetone takes it right off..

[BCRider]

I know you are talking about steel plate gauges like feeler gauges and the like,
but for cleaning dial indicators with the plastic lens, I was always very careful
what solvent to use without hazing the plastic lens. What I have found that
cleans gook well and is safe to the plastic is Hoppes No. 9 gun cleaning solvent.

-D

That's not one I'd have expected. I'll keep that in mind. And Thanks for the hint.

At my place I've had a squeeze bottle of Novus 2 fine scratch remover around over the years for removing fine scuffs that look cloudy or for at least polishing the insides of a deeper gouge to make it look less noticeable. For cleaning I use Plexus and a micro fiber cloth. This has been my go to combo for years worth of plastic face shields on my motorcycle helmets and plastic lens sunglasses. They look new even years later thanks to these products. My typical final damage for them is either sitting on the glasses in the car or leaving them somewhere.

Mind you I just about gagged at the new prices. I thought it was pricey when I paid $19 for the 13 oz spray can about 10 years ago. It's over $40 now.

[metalmagpie]

Judicious use of a glass bead blaster can work wonders.

[Doozer]

I know you are talking about steel plate gauges like feeler gauges and the like,
but for cleaning dial indicators with the plastic lens, I was always very careful
what solvent to use without hazing the plastic lens. What I have found that
cleans gook well and is safe to the plastic is Hoppes No. 9 gun cleaning solvent.

-D

[J Tiers]

Before any mechanical means, including abrasives like brasso, simichrome and such I would try a solvent.

The reason I say that is because many of my tools like what you are talking about look like hell. Brown and tarnished looking. The reason is they have been drenched in a protectant that discolors after years. So when I need to use that tool I soak it in a vat of acetone I have and in 30 minutes its wiped clean. Just a thought. I like the US cleaner with dawn idea also. JR

There is a problem with that approach.

Yes, clean first, I assume the cleaning approach was tried, with detergent or the like. After a while, oil etc can become a hard coat that "cleaning" and sometimes even solvents, don't touch.

Using "strong solvents", purple cleaner, ultrasonic cleaning, etc has a problem. It works too well! And it does not "know" what you want to remove.

So, you remove the "tarnish", and also the paint in the engraved markings. Now your item is squeaky clean, but the markings are still hard to read because they are fully or partly removed to bare metal.

That is where "mechanical means" will shine...pun intended. They shine up the surface so you can see the engraving, but do not clean the contrast paint out of the markings.