Matt - the top consisted of a short front section of mahogany laminated to a much larger rear section (single piece) the laminated pair finished with a layer of veneer. The laminate joint breaking underneath the veneer had caused a jagged crack in the veneer but a clean breakage of the joint in the mahogany. Once the old glue was cleaned off, I had a 'good as new' rejoin of the mahogany (no gap). The trouble was that over the years, as the gap had enlarged, little bits of the veneer edge had broken off - these small, non-continuous gaps in the veneer was what I needed to fill, colour matching the existing top.
Although I'd tested various coloured mixes of filler on scrap (sanded, oiled, ...) and selected what I thought was a close match, the thinness of the fill somehow made it much lighter when in place. The other problem thrown in, was that in some places the two joined edges of the veneer were not quite level so some scraping was needed to bring them back into alignment. Then I had to play around to hide the filler and the scraping - the filler took colour in a different way to the scrapped veneer. So my experiences would lead me to shellac fill (for such small cracks in veneer) if I wanted a more predictable end result.
On the other hand , to fully close the cracks in the veneer, I would have had to planed each edge at least 3mm to give me straight edge of veneer on both sides. Then, as you say I would have had to add at least 6mm to the back edge of the top, in matching veneer on mahogany and with matching contoured edges - this was beyond my skills and would have left a more noticeable repair that I now have.
The item is not particularly rare/valuable (or good condition) - so I was prepared to use it as my first venture into restoration techniques - It's already given me lots of lessons and there are still more repairs that it needs (small area of missing veneer on a drawer front, cracked and scuffed veneer on the curved base, a very poor repair to the side ...)
Colin
Matt@":amtybw95 said:
its perfectly possible to gain an adequate repair using the methods I described (as described). A repair using wax and shellac stick ends up with a crack filled with wax instead of filler. If the crack is then "coloured" to look like grain its easier to do on filler than wax for obvious reasons. If one is replicating grain patterns, flecks and pores using wax stopper/ shellac stick alone then thats a better job - is this what was being referred to by Custard? . A shrinkage crack is a shrinkage crack and a proper repair should always be to close up the crack by whatever means as long as what is done does not affect the integrity of the item. The right way to repair this was to close up the crack and if necessary add a strip to the rear edge if there is no overhang to allow for the closing up. The one thing that screws up this type of job is both sides of the crack not being 100% level. In the end , one has to take a view regarding whether to leave as is or do something invasive and the value/ rarity of the item is usually what dictates that........
