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Category Archives: classical guitar

So far in this blog, I’ve been writing about how instruments are made and showing photographs of what they look like. But what matters most, certainly to players and listeners but to makers too, is what they sound like. The trouble is that it’s not easy to make recordings that do justice either to player or instrument. Having made that excuse, I’m going to try. So here, as a first step, are three short pieces played by Fiona Harrison on this cedar top guitar that I’ve written about before. Click on the labels to hear them.

Piece 1

Piece 2

Piece 3

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This guitar is now completed and is due to go off to its new owner next week. Since I’ve written so much about making it, it seemed worth posting some pictures of it in its finished state. There are a few more in Gallery too.

Unfortunately, the shellac experiments failed to reproduce the problem that I had with the polish that failed to harden. I put blobs of shellac from each of the containers of the stuff that I had in the workshop onto a sheet of glass and left them overnight: all hardened satisfactorily. So I can rule out the possibility that the shellac I was using was too old.

I also French polished a piece of scrap mahogany, using a lot of mineral oil on the rubber and building up a thickish layer as quickly as I could. That worked fine. So Bob Flexner was quite right when he said that it wasn’t the oil causing the problem.

I’m left without an explanation but I have learnt something. First, it’s always worthwhile to check that the shellac hardens using the ‘blob on glass’ technique before starting to polish an instrument. Second, mineral oil is an effective lubricant for the rubber and doesn’t compromise the quality of the finish. And third that, if the polish doesn’t harden fairly quickly, the best thing to do is wipe it off and start again rather than waiting around in the hope that it will harden eventually.

It looks as if  I’m wrong about the problem with non-hardening shellac that I mentioned in my last post. There, I suggested that it might have been due to using mineral oil to stop the pad sticking when applying the shellac. Bob Flexner emailed me saying that neither he nor the hundreds of people that he has taught have ever encountered any trouble with mineral oil. Indeed, the reason that he prefers mineral oil to linseed oil is that unless one is careful in removing all the linseed oil, it cures soft and gummy on the surface.

I’d like to get to the bottom of the matter, not least because I don’t want to run into the same trouble in future. So I’ve carried out some experiments to try to reproduce the problem using various types of shellac in combination with various types of oil to see if they harden differently. If anything useful comes of them, I’ll write about it.

A few weeks ago, I started French polishing a cedar-topped guitar and, to avoid the temptation of rushing to get it finished, I began making another to give myself something to do while waiting for the polish to dry and harden. Absurdly, the strategy worked too well; I became so absorbed in making the second instrument that I didn’t pay enough attention to the one I was supposed to be polishing. This meant that I didn’t notice a problem: the shellac that I was putting on wasn’t hardening properly.

It took me a while both to identify the problem and to come up with a diagnosis. I’d been using light mineral oil on the pad (instead of the usual linseed oil) to stop any sticking as the polish was rubbed on and I reckon that some of this oil had got incorporated into the finish and slowed up the hardening. The advice to use mineral oil comes from the chapter on shellac in Bob Flexner’s book Understanding Wood Finishing, which is otherwise a mine of good sense. It’s possible of course, that I’m wrong in laying the blame at his door but when I eventually bit the bullet, wiped off the non-hardening shellac and started all over again using linseed oil, the problem didn’t recur. I’d be most interested to know if anyone else has had the same experience. Sometime I must make some experiments with different oils to find out whether this is the correct explanation.

All of this inevitably slowed down completion of both instruments and there hasn’t been much to photograph or write about, which is why there haven’t been any posts for the last couple of weeks. Anyway, I’m now at the final stages. Here’s the current state of the two guitars:

Well, here it is all strung up. Too early, of course, to make a judgment about how it’s going to sound. But it’s nice to find that it works and that the frets are in the right place. I’ve given the back a wipe of shellac to bring out the figure.

The guitar you can see hanging up in the background was the last one I made and which is being French polished at the moment. It has been rather neglected as I’ve been making the latest instrument, but now I’ll get on and finish them both off.

The bridge is made out of Macassar ebony inlaid, on the tie-block, with a flash of laburnum to echo the rosette. Earlier today, I positioned it on the soundboard and glued it into place. The clamps are now off but I’m going to be patient and wait until tomorrow before stringing up the instrument. It’s always wise to let the glue cure completely before putting a lot of tension on the bridge.

The fingerboard has now been fitted and fretted to a scale length of 650mm. I’ve more or less finalized the shape of the neck too. Time to make the bridge.

The binding and purfling went in quite neatly. It’s a simple scheme but I think it will look fine on the finished instrument. You can judge for yourself from the pictures. The apparent staining of the wood in some places is where I have brushed on some shellac to stop the white maple picking up dirt or, worse, turning an orange colour from contact with the cocobolo. It will disappear when the next coat of shellac goes on.

The next tasks are to prepare a fingerboard and make a bridge.

The binding is made from sawn veneers of ebony and maple. The photograph below shows a true edge being planed using a shooting board before using the bandsaw to slice off a narrow strip.

Here, a border of maple is being glued to the ebony in a shop-made clamping device.

Below is a strip of the finished binding, bent and ready to be glued into the ledge already routed on the guitar.

Now that the repair that I wrote about in my last post is complete, it’s time to get back to the guitar that I’m currently making. I’ve routed the ledges for the binding and purfling to sit in – a job that I never approach without trepidation since it’s so easy to ruin weeks of work by a moment’s inattention when you’re using a tool whose cutter revolves 25,000 times a minute. Fortunately, there were no mishaps. I never much like using an electric router – nasty, noisy, top-heavy things. But the next task of preparing and bending the binding strips will be easier to enjoy.

French polish isn’t the most hard-wearing finish for a guitar and it’s time consuming to apply. But it does have at least three enormous advantages. The first is that, in spite of the repetitive nature of the process, it’s remarkably enjoyable to do. The second is that you don’t need any kit: no spraygun, no mask, no nasty solvents – just a pad and a bottle of shellac. And the third is the fact that, if it does get damaged, it’s fairly easy to repair.

A cedar top classical guitar that I made a year or so ago got damaged the other day when it was treated like a Stratocaster. A young friend of its owner, keen to show off his skills as a rock musician, strummed it using a pick. Unfortunately, he didn’t notice the marks he was making on the soundboard until there was a comet’s tail of scratches on the treble side below the soundhole.

After unstringing the guitar, I steamed out the deeper gashes where the pick had dented the fibres of the wood and then re-polished the top. It’s not quite as good as new because, if you get the light right and look closely, you can just make a out a faint ghost of the original scratch. I’m not quite sure why but perhaps, where the pick reached the surface of the wood, it exposed slightly lighter coloured wood beneath.

I stupidly neglected to photograph the instrument before I started work, but here it is re-finished, re-strung and enjoying the spring sun while the polish hardens off.

I’ve glued on the back, so the ‘box’ is closed and it’s looking pretty much like a guitar. The next task is the binding and purfling. The cocobolo of the back and ribs has a fine figure and I thought that the straightforward black and white (ebony and maple) scheme that I used for the last instrument would set it off nicely. As you can see , I’ve already made a start with the end block inlay.

The back has now had its three transverse braces fitted. It has been trimmed to shape and the linings of the ribs have been adjusted to receive it. So I’m all ready to close the box.

Well, this was the moment that I was trying to describe. First, the neck was glued to the soundboard. Then the tail block was positioned and glued, the ribs slid into place, and glued at the neck and the tail. Finally, the perimeter of the soundboard was attached with tentellones. Only a day’s work, but enough energy was added to the system (to continue my ridiculous metaphor from physics) to achieve a quantum leap.

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