Substance holding MOP inlay in place

[George Roberts]

This is a guitar that Frank thought was most likely from Markneukirchen, about 1870.  It has been sitting under my workbench for many years (it needs a lot of work).  It is missing a number of the engraved MOP inlays, and I am trying to replicate them.  The inlays are held in place by a black, shiny, substance that has shrinkage cracks.  Any ideas about what they used in those days?

When I was a kid one of the workmen at Gibson (Parson St. Kalamazoo) gave me a small box of powdered walnut shells, and another small box of lampblack.  He told me that they mixed equal parts of each, and added Elmer's glue to get the right consistency.  I still have the two boxes, but was also wondering about using black epoxy, both to fill in the shrinkage cracks, and to hold in the replacement MOP inlays.

Any thoughts would be much appreciated.

George

[Roger Häggström]

I use thin superglue to saturate and stabilize the black filler and fasten the MOP inlays. The thin glue don't fill in the cracks, but I like to keep the old patina. I think the original makers used a slurry of lamp-black and fish glue for the black stuff, maybe the walnut dust too (new to me).

The recipe you gave with lamp-black, walnut dust and Elmer's glue should probably work just fine to fill in the cracks and probably hold the MOP too - even if superglue is the safe bet. Stewmac have tough black superglue that could be used to fill in the cracks.

[George Roberts]

Hi Roger,

Thanks for your reply.  I find it interesting that you try to preserve the "craquelure".  It is part of the history of the instrument, and from that point of view, is worth saving.  The superglue sounds the easiest, but also pretty irreversible.  It is taking me longer than I anticipated to cut out the MOP inlays (to say nothing of the engraving), so I have a while to ponder the problem.