How does it work?
The !nstrumenTool magnetic caliper has been designed for measuring thicknesses of wooden plates on musical instruments. If used on a completed instrument these measurements would include the layer(s) of varnish on the wood surface.
And...it should work fine on nearly any non-ferromagnetic material (ie. nearly anything except steel). So you could measure the thickness of a piece of glass, plastic, ceramic, wood, aluminium or copper as long as the two surfaces of the material are near parallel and it is not thicker than the maximum tolerated by the !nstrumenTool. It also helps if the material can be positioned so that the !nstrumenTool magnetic caliper is being used either
The Roleystone School of Violin Making is now within Araluen Botanic Park in Perth, Western Australia. Here's a link to the West Australian newspaper article, Cottage harmony for carving violins.