I have a full antique box of .44 Colt c.f. ammo. The cartridges were made w/o headstamps. The box has a picture of a Colt open top revolver on the lid. I understand that these boxes are rather valuale in good conditon but this box is in sorry shape. At some point long ago, a thick black substance which appears to be tar or roofing cement dripped onto the box top. Because of this tar or roofing cement on the lid only a small amount of the picture of the Colt is visible. I don’t want to attempt anything on my own. I would like to know if there is anything which can be done to remove the tar and conserve this item?
Anything you try will run the risk of pulling up the paper below, or of smearing and making it worse. At my RV dealership we use solvents to get pine tar and other gunk like adhesives off of campers, but a solvent would ruin your box. If you try to strip it off as is, it will almost certainly take up the paper beneath, and if you heat it, it might spread or bleed through more. Professional conservators have ultrasonic tools that they use under magnification, or special chemicals, but this would all be very expensive.
As much as we love the old boxes and cartons, there comes a time when you simply have to let go. Tape and/or adhesives are one thing. Tars, including black electricians tape, are another thing altogether and usually get worse the more you try to fix them. That’s been my experience.
There is nothing you can do at home. Please don’t even try. Consult a museum or restorer of rare books & paper.
I know of an individual who had a book (rare & valuable & highly sentimental) that had a similar problem. To the best of my recollection the item was frozen with either chemicals or a heavy duty freezer & then the offending materials where removed, slowly & carefully.
Be warned, this is [color=#0000FF]not cheap[/color]. Restoration will likely outweigh the value of the box.
It is as I suspected. It will stay as is for another generation to ponder. Thank you for your ideas and suggestions.