Cleaning Benchmarks

[+Ham What Am]

When I was in the Navy, we used Brasso on all the brightwork. A can of Brasso and an old toothbrush, rag and water bottle in the field kit would do wonders in cleaning the brass benchmark disks (and only the disks) before taking photos.

 

My questions is would this be an acceptable practice or is the "patina" desired?

 

Not sure why I thought of the old Brasso can after all these years, I hated it then.

[Bill93]

The object of cleaning should be only to make them readable. Patina is fine. Readability can be enhanced by rubbing baby powder into the stamping.

 

Brasso is abrasive. Do not use any abrasive, metallic scraper, or corrosive chemical that will remove metal from the surface. Water and a brush will take care of most disks.

 

If painted over, and cleaning is acceptable to the owner of the building or object that it is mounted in, clean paint by using a thinner or other organic solvent (I like carburetor cleaner) and letting it soak for a while.

Edited April 30, 2010 by Bill93

[+PFF]

It's good that this subject comes up, occasionally. Here's what our group has been told:

 

Do not clean benchmarks. Period.

 

It is acceptable to use water, a toothbrush, paper towel, etc., to remove mud so you can read the stamping.

 

As mentioned above, an application of baby powder will make the stamping visible in a photograph. Corn starch works equally well. Both substances are safe and will not harm the metal.

 

And that's where we stop. We don't polish 'em, or apply protective coatings. We report them as leaning (when appropriate), but we don't try to "fix" them. It's tempting. I spent four years at sea and I've got a lot of experience with the amazing BRASSO liquid. But we must honor this position by the monumenting agencies.

 

If it's any consolation, the head of the North Carolina Geodetic Survey has a station (GARY T) in the front yard of his personal residence, and even that disk does not get polished. (But I notice the grass is always neatly edged around it. [Grin.]

 

-Paul-