Rapid prototyping methods are the new wave of engineering. As manufacturing new test design move toward lasercutting and 3d-printing, I’ve been looking into one materials. Foamboard makes a great sounding board, and nobody seems to work with it So, I put together a quick foamboard mandolin based on the Saga Mandolin kit.

Here is the first prototype:

Now, what makes a great sound board? Well first, we need to dive into some engineering terms.

The tone of the soundboard comes down to the ratio of Young’s Modulus and density. Density is the easy one. Mass / Volume.

Young’s Modulus is only used in engineering circles. It is a measure of elasticity. How much will an object strain depending on the stress applied. Or how much will the shape of an object deform based on how hard to you push it down. Foamcore ends up being a very stiff and light material. High modulus. Low density. Its also quite inexpensive, and relative easy to rough cut. So, it works well as a boxy sounding sound board. This research paper by Chris Dunn goes into way more detail.