Advice Requested: Stewart Speedo Refurb

[A Whiteman]

I am looking for advice and guidance on refurbishing a Stewart speedo dial. As can be seen in the picture below, the dial has been affected by copper verdigris.

Can this be easily removed without also removing the black lettering? I have pondered using a mild acid like lemon juice or vinegar.

If cleaning does not work, is it possible to get a reprinted dial face? If so can you advise where or who can help with that?

How is the indicator arm removed? (so I can take the dial face out for cleaning without affecting the rest of the speedo).

I am intending to leave the speedo case as much as possible with the original patina, so cleaning the original dial is preferred to keep with that 'as found' look, just making the markings easier to read.

Many thanks
Adrian

[Kaiser]

The green copperoxide can be removed with a soda-water solution, be sure to start with a very very weak solution and a very soft (kids) toothbrush.
Allways proceed with extreme caution and try to test the solution someplace on the ink where it does not matter too much, in the past all kinds of ink and paint were used to print dial faces, some even water soluable !
(Cleaned a 40s Chrysler speedo once with just water and dishwashing soap with disastrous results, apparently a waterbased paint was used on the face)
The pointer or needle should come right off if you pull it up carefully in the center where it attaches to the axle.
Good luck with the resto !

[A Whiteman]

Thanks Leo