Harry McNamara

week 4: make something big

This week we explore an exercise in large-scale CNC machining out of two 4'x4' pieces of OSB wood

design

We were instructed to make something big. Whales are pretty big. Of course, making a whole whale-sized object out of plywood is not really reasonable. But I decided to adapt a piece of one (specifically the tail) for a furniture design.

My design went through several iterations. The first version (from back in week 0) was of a bookshelf shaped as a whale tail emerging from the water. I decided that since I already had a bookshelf (and that the 4'x4' tool space restriction for the ShopBot would restrict it to be a small bookshelf) I adapted the design to make it a table (either a standing desk, end table, or coffee table, depending on the final size).

machining

I split the final design into two 4'x4' sections to cut from two boards on the ShopBot buddy. I first cut a small test piece on the ShopBot Desktop with press-fit slits of a range of widths around the board thickness (~0.43''). I found the best fit was a 0.47'' slit.

I then exported the .svg (touched up in inkscape after a Rhino export) to a .pdf to import into the shopbot software to define toolpaths. I milled with a 1/8'' downcut endmill; each of the two 4'x4' jobs took about 20 minutes.

I decided to use all of the material to make a standing desk. Overall, I was happy with this as an alpha version. Some of the fits weren't ideal and could be tinkered (especially the top desk - the central fit was slightly off-center, and it turns out the side that would have been up was the bad side of the wood. so I opted to flip it and deal with the misalignment to have a cleaner finish). As a follow-up I might try to make a smaller version, fitting all pieces into a single 4'x4' board for an end table.