Thursday 18 August 2016

5 Shades of Black

People who know I've been struggling with this black guitar have been asking me what's gone wrong. The answer is the black finish but for various reasons. So – those of you who want the details of exactly what has happened and why the top has taken me this many attempts – this is for you.

Attempt 1. I initially had in mind that I would install the rosette in the top and then stain the wood black. The rosette was going to be celluloid with green malachite and neither would allow the stain to soak in, it would sit on top. I havent worked with celluloid much before and polishing it did something strange to the grain of the surrounding wood. It didn't look bad, just slightly different from elsewhere, an almost zig zag effect. I thought the black stain would hide this but unfortunately the Spruce took the stain differently in this area, it wouldn't go fully black. As the spruce was now damaged I needed to start the top again.

Attempt 2. Fortunately, as I confessed recently, I had another guitar on the go and this kit was only being partly used. For Jonathan I had substiuted a Red Canadian Cedar top because he likes a mellow sound. This left me with a spare spruce top so with a Blue Peter 'here's one I made earlier' flourish I started work on that. I thought I might be better off appying the finish to the guitar and inlaying the rosette afterwards. Thinking that this may require a thicker finish I added Wudtone's black guitar finish to the process. Stain, deep base coat, black top coat, clear top coat. Each stage needed several applications and therefore drying times. Again I got on with Jonathan's guitar while I literally waited for the 'paint' to dry. When the finish was complete, I carefully covered and masked the top and prepared to rout the circular slot for the rosette. I hadn't removed Martin's pre-existing black and white rosette thinking this would easily be removed by the routing. The black and white bands were easily removed but plastic is harder than Spruce and despite my best efforts a small strip of plastic dented the finished black top. I attempted to patch the finish but with no success. So, I scraped and sanded the black finish back to almost bare wood and began...

Attempt 3. This begins with a routed top that again needs finishing. I went through the stages and once again got on with the other project between coats. I also braced the back and sides of M's guitar and did the Fox inlays. As I reached the top layers I realised that the thickness of the finish was very difficult to keep even near the routed slot and soundhole. The edges seemed to go back to light wood with each gentle 0000 wire wool rub down between coats. I tried a slightly thicker application and this created an unsightly ring around the soundhole – no good at all! With the routing already done and the realisation that this finish would not work unless it was done before this stage I began...

Attempt 4. I now needed another piece of wood so a call to Dave Dyke's luthier supplies and a bill that was not in the budget took care of that. The new Spruce arrived but I had to joint the top, they are always made in two halves, before beginning. The finish on the previous attempts had been somewhat inconsistent. The black base coat had a tendency to remove previous layers on application. In order to achieve an opaque finish I read some other people's experiences with Wudtone and decided to try a slightly different approach. A thicker coat of base finish on a slightly rougher wood. Cutting a long story short and abbreviating attempts 4a, 4b and 4c. This wasn't successful! I have applied and stripped (inhaled despite using a mask) 4 batches of finish. At this point well meaning friends who asked 'what exactly was the problem with the finish' may have received a terse 'it's COMPLICATED!' I tried again building the finish up in thin layers but it just wouldn't take consistently to the new top. Each time on one area, an area of grain that would lead to a knot, the base coat always removed the lower layers of colour. It seems that every piece of wood is different. Soooooooo...

Attempt 5. In between working on the top I applied the black finish to the mahogany back and sides and, if I do say so myself, it has come out beautifully. This left me two options: 1.Change the top to mahogany. A different sound but a good chance that the finish would work. Or, 2. Try a different approach on the spruce. Soft woods and hard woods do behave differently so maybe treating them differently would be the key. I reverted to plan A. I invested in some good cabinet scrapers and a tool to make sharpening them easier (sharpening cabinet scrapers is an art form of its own in my opinion and one I haven't mastered). I worked on the spruce until it had a very very fine finish and then I applied the stain. I used several coats to make it very dark and then used the clear neck finish from Wudtone. The neck finish has more traditional lacquer in it and I thought it would seal the colour well – it did! The finish on the top is not quite the same as the back and sides but it is black and it is a different material after all.



After the black finish was done I covered the whole top in low tack masking tape and routed the slot for the rosette. I routed another piece of wood at the same time and created the rosette in that. As it was being installed after the finishing was done there was no need to use celluloid and I reverted to the original plan of maple and black fibre purflings. Once the rosette was complete I polished it in the wood it was created in and then routed it out to install in the real top. Then I added the soundhole. Next I will brace the top ready for gluing to the back and sides.







3 comments:

  1. I am exhausted reading this story, goodness knows how you have kept going? Any chance of a matching 12 string xx...and uke?...xxx

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