CLPEX Chat Board

I am looking for some ideas on separating two layers of plumbers putty that have various sizes of nails as fragments (shrapnel). I want to examine the surfaces sandwiched together for prints. I have tried cold (freezer) and heat (60 C for 2 hours) to remove the both layers from the metal surface of the can that they covered. Heating seemed to work better as it softened the putty slightly, but still crumbled a lot.

Any ideas would be appreciated.

Thanks,

Terry Marabito
Ohio Division of State Fire Marshal
Forensic Laboratory

With all seriousness, did you ask a plumber? I am sure they have more experience with plumbers putty than anyone else.

Just an idea. I certainly haven't tried it, so it would need some experimentation on a dummy setup.

If it's really plumber's putty, it clay and oil, probably linseed oil, although there are other formulations, but they're all some form of pulverized stone and oil. Now, glazier's putty is similar, usually a compound of calcium carbonate and linseed oil, and it also sets up as the oil dries. Because glazier's putty is used where it must be periodically removed and renewed, there are a couple of methods of softening.

On is to apply kerosene, which penetrates and combines with the linseed oil to form rosin, making the putty soft again. The other method is too destructive to apply to your case. I have no idea if softening will permit the pieces to be separated at the faces, but I kind of wonder if kerosene was applied to one piece, if some periodic gentle attempts might discover the point at which the rosin conversion just reached the interface.

Thanks Biano, I will start calling some places today.

Gerald,

I have been thinking along the same lines. I looked at the MSDS sheets and found DAP and other manufactures which list the solvent/softner as a Naphthenic oil with CAS # 64742-53-6. Looking on-line for products that have this liquid, I found that Cutting Oils are largely made with this compound. Guess I'll crack open my wallet this weekend at the "home" store.

Thanks so much.