I filled any voids and made good the join between the veneer and the edge binding where necessary using Milliput white epoxy putty. This sets rock hard but has the advantage of being able to be wiped off with water during the workable phase. I masked off the join with 3M blue vinyl tape to obtain a sharp, well-defined edge. Some luthiers prefer to adhere the plastic edge binding by softening it with acetone (2-propanone) or using a binary mixture of acetone and dissolved plastic pieces as the adhesive formulation. Although I would not seek to dissuade anyone from using a system that they are accustomed to and works for them, my preference is to avoid using acetone other than as a general purpose solvent for the following reasons:
(a) it is a very aggressive, volatile polar solvent which will quickly attack many plastics and thus is difficult to control
(b) the softened plastic can easily bleed into the grain of the adjacent veneer yielding a non-uniform, untidy edge.
Great care should be taken when abrading knife cut marquetry veneer which is generally only around 3/128″ (0.6 mm) thick. It is worth considering using a plasterer’s float with abrasive paper mounted to it for flatting. These have a large, uniform surface area and can be obtained at low cost in all DIY stores. Some have multi-layered beds with foam and rubber and are ideal for flatting guitar bodies.
Once the binding was satisfactory, I removed any surface scratches in the veneer with careful abrasion then applied black Jecofill brand grain filler by W S Jenkins using sponge applicator pads on wooden sticks. Rather than applying a thick layer, leaving the grain filler to dry overnight then abrading it as I did on the 3/4 scale Red Special build, this time I removed it with a kitchen cloth around 5-10 minutes after application then wiped over the surface with white spirit. This saved effort and achieved the required result. Grain filler has the unfortunate side-effect of accentuating any remaining flaws present in the surface which will require to be addressed before wood stain and clear coats are applied.
I prefer black grain filler because this accentuates the chatoyancy (Tiger’s Eye) characteristic inherent in the mahogany and looks very similar to Brian May’s Red Special, although of course, a neutral or brown filler can be used if this is your cosmetic preference. The appearance of the wood changes quite unnervingly at each stage of finishing; after this treatment, the colour of the wood alters from a salmon pink hue to a walnut brown. After applying the mixture of red and brown Rustins stains, the wood can appear a disappointingly dull pinkish red but changes dramatically once again when the clear lacquer coat is applied [see attached images of the test blocks I prepared some time ago].
Moving onto applying the stain, I decided to use only red mahogany Rustins wood dye instead of the 80:20 red/brown mahogany mix I used on my 3/4 scale Brian MAy Red Special build because the veneer turned out to be very brown after removal of the grain filler. I understand from Greg Fryer that Brian applied only red mahogany Furniglas brand wood stain to the original Red Special and over time, the hue has faded/changed to a more orange-brown. Finding a suitable stain to yield an authentic representation of the original guitar is therefore a challenge.
The photographs included with this article illustrate the body before I cleaned up the binding. They accentuate the redder hues and from certain angles the brown colour of the veneer is more obvious. However, as you will see in later articles, the hue is both authentic and pleasing once the clear lacquer was applied. The colour intensity is greater than on the test blocks I prepared. I applied two light coats of the wood dye with the sponge applicators and let it dry overnight before lightly wiping off any excess dried stain from the surface. The stain does not penetrate easily once grain fill is applied, removed and the surface dressed with very fine (000) grade steel wool or a fine grade abrasive.