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The soprano ukulele that I made from scraps of wood too nice to throw away (but too small for anything else) turned out to be a nice sounding and surprisingly loud instrument. I thought it would be fun to make another.

The classic wood for ukes is Koa, a tree in the Acacia family, which grows only in the Hawaiian archipelago, although it’s closely related to Australian Blackwood (Acacia melanoxylon) and the wonderfully named – after its smell when sawn – Raspberry Jam wood (Acacia acuminata). I was pretty sure that I remembered having a set of Koa somewhere in my stash of guitar wood and eventually I found it.

After a bit of thought, I reckoned that there would be enough material for two ukuleles – one soprano and one tenor. However, as soon as I began to clean it up with a view to book-matching fronts and backs, I ran into trouble. The Koa had a beautiful and dramatic figure, but it was very difficult to plane without causing tear out. That’s often true of highly figured woods of course, but this this was much worse than usual.

A drum sander would have solved the problem – except that I don’t have one. So I tackled it in the old fashioned way.

First I used this large scraper plane to produce a good surface on the face side of each piece before gluing them up, book-matched, for fronts and backs.

 

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Now, working from the other side, I needed to get them down to a thickness of under 2mm. Fortunately, the wood had been well sawn and was only around 3mm thick so there wasn’t too much material to remove. This Krenov-type plane with a short thick blade set at an angle of 55° performed better than a plane with the usual 45° blade angle. There was still some tear out, but it did allow me to approach the final thickness without too much anxiety.

The plane was made by David Barron and it’s nicely designed with a soft rounded shape that’s comfortable to hold. It has a sole of lignum vitae and a fairly tight mouth.

 

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For the really difficult patches, where the grain was running all over the place, I switched to a toothing plane. This one is a lovely old tool made by Varvill and Son, York, well over 100 years ago. It bears name stamps of two previous owners but it’s in such good condition that I suspect that more of its life has been spent in a tool chest than on the bench. It’s really intended for preparing a surface before laying veneer and, although it’s able to flatten the wildest grain without tearing it, it removes wood very slowly.

 

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To speed things up in the less wild areas, I used an ordinary No 4 bench plane fitted with a modified blade. I’ve written about this blade before, so I won’t repeat myself except to explain that the rationale behind it is that the individual serrations are too small to grab and tear out large chunks of wayward grain while, at the same time, being wide enough to remove material fairly quickly – certainly a lot faster than the wooden toothing plane.

 

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Having got close to the final thickness with this pair of toothing planes,  I finished the surface with a small Lie Nielsen scraper plane and an ordinary cabinet scraper.

 

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Here’s a line up of the workhorses that I put to use.

 

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And here are fronts, backs and ribs ready to assemble.

 

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A while ago, I wrote about using a Millers Falls scraper plane to cope with some highly figured cocobolo that I was using for the back of a guitar. It’s an excellent tool for finalising the thickness and it leaves a clean finish even on the most awkward wood. The disadvantage however, is that it takes only the thinnest of shavings so if you’re starting with wood that’s way too thick, you’re in for a lot of time and effort to get to the right final dimensions.

Of course, the usual way to get around the problem is to run the wood through a drum sander. But I haven’t got one, partly because there isn’t room for it in my small workshop and partly because I’m allergic to sandpaper. I don’t mean it literally – I don’t come out in a rash if I touch the stuff – but I do think that there are nicer and quieter ways of shaping wood than grinding it into dust.

Another solution is to use a plane with a toothed blade. This won’t eliminate tear out completely but, should it happen, it’s limited and shallow and can easily be dealt with by a scraper later. Toothed blades work because the individual teeth are too small to grab enough fibres running in the wrong direction to rip out a large lump.

I use a No 4 Record bench plane fitted with a standard blade that I modified to look like this. Put the blade in the vice, cutting edge upward. Take a cold chisel and, against all your instincts, hammer a small gap into the cutting edge every 3 or 4 mm. Then sharpen the blade in the usual way.

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Another way of cutting the teeth is to use a thin grinding wheel in a Dremmel.

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Here are a couple of pictures of a guitar back in zebrano being thicknessed with the toothed blade. If you’ve ever used this wood, you’ll know that the interlocked grain structure makes it very hard to work. With a toothed blade and a wipe of wax on the bottom of the plane, the task becomes a pleasure.

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The marks left by the toothed blade are just visible running diagonally from bottom right to top left. And you can see the linguine-like shavings that are produced.

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Switching over to the scraper plane for final adjustment of the thickness and to remove the corrugations left by the toothed blade.

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