The uke is now playing 🙂

Some more pictures…

Old Stanley Knife blades made excellent scrapers! The steel is good quality and nicely hardened, plus I’ve always got lots of old ones around. They make a nasty crunch when burnished but work well and hold an edge for ages.

Made a bridge. This is based on the shape violin bridges – not sure about it yet but we’ll see.

I got the soundboard finished off.

I came to the conclusion that it wasn’t worth using the existing soundboard – it just doesn’t ring nicely. So I tapped all my lumps of wood to find one with a decent sound. The best was some mahongany.

Glued the veneer to the headstock and drilled the tuner holes.

Got the fret slots cut. This is always a scary job since one slip wrecks the piece.

This is my process – I’m sure there are better ones. But this works for me for now.

Oh no – not another uke!

I’ve sold the Mostics 3018 CNC – it was just far too unreliable. It broke my heart everytime it went wrong and chewed up hours of work. So I’m not working on the Archtop Pineapple Uke at the moment.

Instead I’m making a conventional ukulele – flat top with braces – from reclaimed wood from an old desk. The draw sides and bottoms are make of some of the finest cedar that I’ve ever seen – lovely stuff. This will be used for the soundboard. The rest of the uke is made from mahogany – some from the desk, some from a chest of drawers and some from some wood my dad gave me.

As you can see from the last photo, the back and sides are fitted inside the sides of the uke rather than being glued on top of the sides. This is basically because I think it will look nice and it means I won’t have to bind the edges. However, it isn’t easy to do – the bending of the sides is far more visible and getting the back and front to fit exactly is tricky. Going ok so far – the photo above shows the back.

Some of the literature on violins suggests that the shape of the cross-section of the top and back is based on cycloids. Whether this is actually true is a matter for debate. Certainly much of the shape of a violin can be generated from circles so it is certainly possible that the masters based the shape on a cycloid which is generated from circular geometry. However, some modern makers say that they shape the top until it looks right rather than until it matches a template, so requiring the shape to fit precise geometry is probably requiring too much precision from the process.

Regardless, here is a script to generate the shape of the top of an arch-top string instrument using curate cycloids. I’ve written it in Python. I’m not experienced in Python so please excuse any errors and let me know how it could be better in the comments below.

The script takes in a PNG file that holds the shape of the long-arch down the centre of the instrument, plus the shape of the edges of the curved section. Using a PNG to hold this information means you can generate these curves however you like.