A variety of things. for some time I worked for a company creating 3D models for their military training simulator. This was an extension from designing 3D models that were unfolded and printed on card for model railways. Now I use the same techniques to create physical models on a 3D printer. In the past I've built furniture out of wood. In the homemade tools I once built a wood lathe, a 12" disk sander, a free standing belt sander and various jigs as I've needed them.
Currently I'm building a greenhouse, the biggest project I've ever tackled.
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