Curve tracing aid

[mklotz]

A friend had a model ship he had built. He wanted to cut a hole in a board such that the ship would fit into it at the waterline (part of a model railway display). So, how to transfer the cross section of the hull along the waterline to a flat surface. Lacking a CMM, I remembered something I'd read about in my own youthful ship modelling days and made this...

The block of wood has an angled hole to fit a pencil. With a pencil in place the point touches the paper at a point in the same vertical plane as the narrow side of the block. Thus, as the narrow side traces along the waterline, the pencil traces out an image of the cross section.

Obviously, very few of you will ever encounter this problem. This post is meant to document the idea in the hope that some of you might remember it and find it useful someday.

[kbalch]

Thanks Marv! I've added your Curve Tracing Aid to our Measuring and Marking category, as well as to your builder page: mklotz's Homemade Tools. Your receipt:

Curve Tracing Aid by mklotz

tags: marking