Cast Brass Letter Clean-Up

[dave parr]

I had to clean up a set of brass letters. They have been out in the field for probably fifteen years and had tarnished under the clear coat. They are 10 inch letters, so they are fairly easy to handle. The customer wanted the sign refreshed -- repaint the background plate and bring the luster back to the letters.

I removed the letters from the aluminum pan background. I stripped the clear from the letters with lacquer thinner, and buffed the tarnish off with a fine wire wheel in a bench mounted buffer. I next cleaned the residual with Hagerty Heavy Duty Copper, Brass & Metal Polish. Once the Hagerty was dry, I wiped it clean and polished the letters using a 12" soft cotton polishing wheel. The wheel is mounted on a pedestal buffing abhor and loaded with co**** Menzerna polishing compound. I plan to re-clear with Grip Guard Plus clear.

The letters turned out looking great, so far, but I'm curious how other folks are handling this sort of project. I've read about the salt and vinegar paste but have never tried it. I've read about acids but it's been a while and recall very little of that. So, any other methods? Anyone try the salt and vinegar method?

Thanks in advance.

[Wayne]

Hi Dave- I have used concrete and brick cleaning acids before to clean up old brass and copper- it gets the brown stuff off- but the real hard work.. ( Y'know- the shiney stuff that really makes the difference)..is down to elbow grease and lots of rubbing.

[dave parr]

Thanks, Wayne. This might come in handy for the smaller letters where the inner surfaces are a bit harder to get at with a buffing wheel. I like to make it easier on the fingers when I can, but I suppose one has to just get on with it occasionally. The buffing wheel isn't really an easy job, just a different kind of strain.

I imagine there is a solution that one can place the tarnished pieces in, leave them be for a time, and remove them bright and clean; perhaps a little polishing would be needed to finish them up. This could be an active imagination or wishful thinking. :o

[Chunkie]

You could try electrolosis.

I have used it to clean rusty steel and it works very well. You have a s**** piece for the positive and ensure the piece to be cleaned is the negative and place in a solution - add a current and leave for a few hours. You end up with a very clean piece and the s**** is destroyed.

Just make sure you get the terminals the right way round - don't ask how I know!:roll:

Not sure if it will work as well on Brass etc but it is the same principle for all metals - check this link....

http://www3.telus.net/public/aschoepp/electrolyticrust.html

[dave parr]

That's some interesting information there, Craig. Thanks. I've done a few searches for electrolytic brass tarnish removal since you posted this. Opened up more than I had known before. much appreciated.

I put the clear on today. Painted the panel then mounted the letters late in the day. I'll have to wait for the next one to try the other methods. I could run some tests, I'll keep my eyes open for some test pieces. I watch that terminal arrangement, though. :shock: