Old Oscilloscope Brass Faceplate

[David Simpson]

I've a thread running in 'Test Equipment' about an EMI W.M.1 Oscilloscope. The faceplate was showing signs of paint chipping & general wear & tear. I also put a post in 'Services Required' but no takers.
So - bit the bullet. Its made of sheet brass and has a hard resinous slightly mottled paint finish with a clear lacquer top finish. No way was I going to use anything seriously abrasive, wishing to retain the decent etched lettering. No wire brushes, emery cloth, etc.
First - tried Nitromors - no effect whatsoever.
Next - tried burning off the lacquer & paint with a garden gas lance - a wee bit of paint started to lift but was halted by the heat dissipation qualities of the brass.
Next - the big fella - a roof felter's propane torch - paint bubbled & burnt off.
Next - another scrub with Nitromors, a thorough wash, and a further soak in fresh water.
Nest - a jolly good rub down with medium, then 000 fine wire wool soaked in cel. thinners. That's all the paint removed, but the lettering remaining pristine. Some blemishes remain, but shall start rubbing & polishing with Farecla paste.

Regards, David

[Diabolical Artificer]

I had a look at your post in "Services Req" David as I have a steady hand with a paintbrush, and can do fine detail, but for the life of me I couldn't work out how to get the paint off, without destroying the lettering. I still can't work out how the dickens you'll be able to paint it without obscuring the lettering or indeed how they did it in the first place. I did think it might be possible to cut the paint pack with an abrasive, but that would have been a mammoth task.

Nice work, take my hat off to you for takling the job.

Andy.

[David Simpson]

Right enough Andy, this was a venture into the unknown for me.
Met up with a couple of Forum chums up here, on Saturday, for cuppa, cherry scone & a natter. Faceplate produced, problem raised, advice given, decision made - will blacken lettering with ink or paint, then just spray over with clear lacquer to leave a nice shiny brass finish.
The polishing with Farecla cream has gone well, but some small slight copper coloured blemishes remain. Only hard abrasives would get rid of those. Bollox to that. As this scope is only several years younger than myself, who am I to complain about several wee blemishes. Seeing as both it & myself are still working within spec.

Regards, David

[peter_scott]

It looked very good in the original crackle grey. Would you not consider returning it to original?
https://www.vintage-radio.net/forum/...d.php?t=111781

Peter

[David Simpson]

Hi Peter,
The steel casing, actually, isn't too bad. With a bit of cutting with the paste, it'll polish up a treat & retain its original paint finish.
I did ask someone to take the faceplate job on, but they didn't do brass. No one responded to my 'Services Request', so its just down to me. I'm just not confident enough to get the paint spraying correct, whilst leaving enough of the fine lettering/numbering indentations to take sufficient white paint. The lettering/numbering/marking is jolly wee. I managed to paint the faceplate of my Coastal Radio Nimbus Tx several years back, and do the etched lettering/numbering etc., but it was bigger & deeper into the steel faceplate.
Lacking expert assistance - fit div I dee ?
The last time I used that epoxy resinous crackle paint - was 46 years ago. Scrounged a tinny of RAF grey to paint my diving cylinders. Lasted for years, wonderful stuff.

Regards, David

[David G4EBT]

It might be worth asking a powder coating company for a quote and to see what finishes they can apply. I go to an Autojumble every couple of months on the outskirts of York where a small outfit have a stand with examples of the sort of finishes that they can apply. A really wide range in fact, including crackle and hammer. Not as expensive as might be imagined, considering that a couple of 'rattle cans' of primer and top coat won't leave much change out of £20.00 and even then, might not produce a result that's to your liking.

Every town has little firms like that who don't mind taking small jobs on.

The only satisfactory way I've found to fill in etched lettering (on knobs and the like), is to apply white (or for an aged appearance 'antique white') enamel such as Humbrol modelling paint, not worrying too much about going outside of the letters, then to let it dry, and wipe off the surplus with a thin cotton cloth such as an old hankie, dipped lightly in enamel thinners. (Not cellulose of course). As you say, the problem that might arise is that unless the paintwork applied is quite thin, it risks filling in the etching and losing definition of the lettering.

Best of luck with it David.

[David Simpson]

I've had bad experiences with local 'body shop' type folk in the past. They don't have an affinity for vintage test equipment casings & faceplates etc. Nor the types of grey paint usually found on old RAF or similar equipment. Army colours & paint jobs - yes. Restoring old Landrovers & trucks is quite the thing up here.
One guy did do a good job on sand blasting an aluminium casing of a Woodsons Spey Marine Tx which had been badly corroded, and put on a nice al. primer. But wouldn't do the complete paint job.
Me - I've been a fan of the wee shaking/rattling spray tinnies for some time now.
It was the novelty of lacquered brass which appeals to me. Reminiscent of Victorian era laboratory equipment.

Regards, David