Restoring the scale on engineering tools

[Steve355Participant @steve355]

[Steve355Participant @steve355]

Hi

I’m completely aware that I am an idiot for doing this, so please don’t think I’m under any illusions.

I recently got hold of a vintage Moore and Wright protractor from eBay, it looks like a fantastic little tool. However, being vintage, it was covered in years of gunk. In my infinite wisdom, I thought I would put it through my ultrasonic cleaner. However, as well as removing the gunk, my ultrasonic cleaner ultrasonically removed quite a lot of the scale ink.

I actually have several vintage engineering tools, which have been polished one too many times, and the scale has faded.

Does anybody have any tips for restoring these scales? The indentation marks are still there, I would guess it’s just a question of applying the right type of ink.

thanks

Steve

[Mick B1Participant @mickb1]

Similar instrument, similar issue:-

…though on mine, the filling looks more faded than removed.

I'll watch this thread, in hope…

[Mike CrossfieldParticipant @mikecrossfield92481]

There are 3 techniques that I've used:

Firstly, you can fill the engraving with paint such as Humbrol, then wipe off the excess before the paint has fully dried. Trick is to use a piece of newspaper lightly soaked in white spirit as the wipe.. Done carefully, this will clean the surface and leave the filling intact.

Another method is to use engraving wax. Usual method for clock dials. Heat the surface until the wax will melt onto the surface, then when it's set hard you can scrape/sand the excess off. Warm up again to restore the gloss finish on the wax.

Last method is to immerse the item in blacking solution. After blacking, the surface can be polished up with very fine emery or wet&dry paper, leaving the scale blacked.

Example of a scale that I blacked using the last method:

Mike

[Robert Atkinson 2Participant @robertatkinson2]

A Lacquer-Stik Paintstick is the best option for engraved marks.

Random googled supplier

https://www.micro-tools.de/en/Paint-oxid/L51123.html?isextsearch=alist

EDIT:  Instructional video (reversed colour)

Robert G8RPI

Edited By Robert Atkinson 2 on 05/11/2021 15:38:40

[Steve355Participant @steve355]

Thanks all, that is very helpful. I will give one of the above methods a go.

cheers

Steve

[SamsarandaParticipant @samsaranda]

I think many years ago Indian Ink was used to fill the engraved marks although I have no idea how it was applied or how effective it was. Dave W

[Mick B1Participant @mickb1]

I think it's Mike's Humbrol method for me. The newspaper technique looks practical – last time I tried it I used a rag with white spirit and that washed out the paint from the engraving as well as the surface.

I've never come across engraving wax, I can't source LacquerStik for a sensible price, and gun blue ain't never gonna work on stainless.

Thanks from me too, folks.

[ZanParticipant @zan]

Nowt to loose, if it pulls the paint out your back to where u started!

a wifi of meths on a felt pad worked well for me while removing the top painting on etched engine plates to leave the brass shiny against the sunken background

[gerry maddenParticipant @gerrymadden53711]

Thank you Robert for the pointer. I'll give this a try.

Gerry

[Clive FosterParticipant @clivefoster55965]

With any paint method its important that the paint is actually thin enough and flows well enough to fill the grooves. On fine scales ordinary paint tends to have enough surface tension to skin over however hard you try to work it in.

Multiple dust coats from an aerosol interspersed by careful polishing off every few dustings has worked for me but I'm not in love with the idea. If there is ever another time I plan to squirt some aerosol paint into a small container, thin it even more and try brushing with a fine artists brush.

But I shan't loose sleep if there is never another time.

Clive

[Mark RandParticipant @markrand96270]

I use Markal paint sticks applied cold, followed by wiping with a lint free cloth. I bought a box of them 15 years ago for stock marking and I've still got most of them.

Engraver's wax is readily available and can be found with the search engin of your choice.

[bernard towersParticipant @bernardtowers37738]

If the scale has any chromium content the blacking idea won’t work, don’t ask me how I know!

[Mark RandParticipant @markrand96270]

The result does look good though!

[Adam MaraParticipant @adammara]

When we were engraving brass or aluminium, we used black cellelose paint , cleaned off with cellelose thinners and polished. You could get it in small quantities those days (1/2 pints!), but it does not seem to be readily available these days.

[Author]

Posts