Repairing wax

Susan White <smwhitewhite [at] netscape__net> writes

>I have a 19th century wax bust made in Russia which is cracked into
>two pieces.  I have yet to find a good adhesive for making
>structural repairs to wax and was wondering if anyone has found one.
>Any advice would be greatly appreciated.

I recently repaired a wax portrait and was very nervous about a
proper adhesive choice.  I was very careful to choose an adhesive
that can be reversed again without affecting the base wax material.

In my case the wax was very resistant to acetone, so I tested three
possibilities that I thought would have enough tack, flexibility and
strength to do the job and still remain soluble in acetone:  a PVA
emulsion, Lascaux acrylic emulsion paste and Primal WS24 acrylic
dispersion.  The last one was the best in terms of adhesion to the
wax, and strength and flexibility when fully dry (tests patches on
wax were left for one month, and thin samples on silicone release
paper were baked at 115 deg. F for two weeks to get a better idea of
the final properties).  The item I mended was small, so strength was
not so important as for a larger object, but the join was pretty
thin and I found the object quite stable to handle afterward.

I would suggest doing some adhesion tests on the underside with
variety of adhesives and see what you think.  The mend I did will
never be tested very stringently, so I can't advise you for certain,
only share my experience.  I was surprised that the Primal performed
as well as it did, since one would not expect it to adhere well to
wax.  It could be peeled off without affecting the wax, but not
easily.  And if the join has lots of texture to it, that will aid in
the gripping of course. Good luck,

Linda S. Roundhill
Art and Antiquities Conservation, L.L.C.
18121 157th Ave NE
Woodinville, WA 98072
425-481-0720


                                  ***
                  Conservation DistList Instance 19:32
                 Distributed: Tuesday, January 10, 2006
                       Message Id: cdl-19-32-005
                                  ***