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Brass Cemetery Plaques are Tarnishing

 

HI,

OUR COMPANY MANUFACTURES BRASS CEMETERY PLAQUES. THE BRASS IS ETCHED IN ferric chloride ⇦ this on eBay or Amazon [affil links] , THEN A TWO PAC BROWN POLYURETHANE COATING PUT ON. THEN WHEN DRY THE SURFACE IS SANDPAPERED TO SHOW BRASS letterING ON A BROWN BACKGROUND. A CLEAR TWO PAC POLYURETHANE IS THEN APPLIED TO THE SURFACE. THE PROBLEM BEING IS THAT THE BRASS THAT IS SHOWING THROUGH THE CLEAR TARNISHES UNDER THE CLEAR COAT.

IS THERE SOMETHING THAT CAN BE APPLIED TO THE SURFACE OF THE BRASS letterING THAT WILL NOT EFFECT THE POLYURETHANE BACKING OR THE ADHESION OF THE TOP CLEAR COAT AND PREVENT THE TARNISHING.

ROB M [last name deleted for privacy by Editor]
PHOTO ENGRAVERS - ADELAIDE, AUSTRALIA

Hello Rob,

How long is the bronze exposed after sanding and before coating? Do you clean the ferric chloride ⇦ this on eBay or Amazon [affil links] off of the piece before the coating is applied? I'd think the clear two-part urethane would be the best way to stop oxidation. I'd try sanding and then wash the exposed lettering with acetone ⇦ this on eBay or Amazon [affil links] Warning! highly Flammable! or a cleaning thinner just prior to the top coat.

Good luck,

Jake Koch
G. J. Nikolas &Co.,Inc.

Bellwood, Illinois

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I am a local history librarian who has inherited the brass plaques from a memorial wall (now demolished). The plaques themselves have been out in the weather (of course) for some time. I would like to clean them for photocopying so that the photocopied information is readily accessible to Local and Family History researchers. The gentleman who will clean the plaques prefers not to use abrasives as it apparently takes off the clean edging of the lettering. It has been suggested that I use a phosphoric acid dip or "Bright Brass Dip". Can you suggest a 'recipe' to make this or where I can get it...?

Many thanks,

Beth H [last name deleted for privacy by Editor]
- Queensland, AUSTRALIA

Q. Hi,

I have my grandparents' original plaque after we had to get it altered after putting my auntie's ashes with them. My dad used to clean it but he has passed away as well. I want to give it a polish and get the tarnish off. Can someone please recommend what I can use to get it back to or close to the original state as I now have it in the garden.
I eventually want to get it mounted on something so it lifts it off the ground

Garry Cole
- Warner QLD Australia
January 30, 2012