Having designed my last classical guitar using a great parametric freeware drawing package called Solvespace I decided to try and do the complete cello design using this package before cutting any wood. The way I look at it, if I’ve thought enough about the design to be able to draw it, then I am going to have a much better chance of building it without making stupid errors.
I started by trying to replicate the Strad body design from the book by H S Wake. At each iteration of the design I printed out the outline full size on multiple A4 sheets and then stuck them back together with sellotape before cutting out the outline shape with scissors. After about 10 iterations I had pretty much worked out how to draw the shape and got it within a mm or 2 all round.
Next I iterated the design for a string length of 695mm giving a neck length of 280mm and f stop of 400mm. It also had a slightly longer body (755mm) and slightly wider waist (240mm). I then tweaked the design until it looked right – particularly round the corners.
Before I started cutting any wood I also tried to get the ff holes designed on so that they met a few key criteria and looked right:
- Outside of top and bottom holes equidistant from cello edge
- Centre ff-hole “V” level with centre of bridge
- Centre of top ff-hole and centre ff-hole “V” equidistant from bridge centre
- Inside of top ff-hole vertically above outside of bridge foot
- Top of bottom ff-hole level with purfling of bottom corner
The parametric drawing software was a brilliant tool for achieving this and the result looked about right to me. The resulting design is here:
Links to the rest of the process following the design are below:
