Thanks all for the input! Ah - I see opinion divided along the classic lines: tradition vs innovation, neophiles vs nostalgics, moderns vs romantics - with the moderns, at least among those who spoke, seeming to have a slight edge.
turboyeast wrote:You've been meticulously trying to reborne a Aurora Brugnetti.
While this was certainly true to a great extent when I started the project, there were a number of decisions that have been taken along the way that make the machine a departure from the Brugnetti original. Obviously, there are significant upgrades on the inside, but there are subtle changes outside too: the level gauge is gone (too 19th century!), the manometer is flush-mounted and the whole exterior has been re-designed with a one-piece bonnet; all, I think, slight refinements on the original. Additionally, in what I think is a fitting celebration of an object designed with longevity so thoroughly in mind, all that was plastic is now wood. Plastic manufacturing is (more often than not) an additive process - as in this case with the original injection molded plastic handles. Making things with wood is (with a few notable exceptions) a negative one: material must be removed from the stock to reveal the form inside. It is a very interesting problem that designers face when they are negotiating the relationship between form and material. I'm reminded of architect Louis Kahn's famous quote:
''If you think of Brick, you say to Brick, 'What do you want, Brick?' And Brick says to you, 'I like an Arch.' And if you say to Brick, 'Look, arches are expensive, and I can use a concrete lintel over you. What do you think of that, Brick?' Brick says, 'I like an Arch.' And it's important, you see, that you honor the material that you use. [..] You can only do it if you honor the brick and glorify the brick instead of shortchanging it.''
Louis Kahn - see the not-so-subliminal arch?
The positive molded plastic wants to be in the form of the original handle, the wood does not.
I can make handles
that look like the old ones, but they are not
true reproductions because they aren't made with the same industrial efficiency as the originals. A philosophical difference perhaps, but one that has a impact on the bottom line: if you prefer the old design, and want it made of wood, would you pay, say, $150 more than for the new design which is functionally equivalent and also made of wood?
Thinking that I know what the answer to that question is, I went ahead with the first production run.
A tray of rough-cut-to-length eight-sided hexagons - material-wise, the most efficient way to inscribe a hexagon in a square - and a lot faster than making round pieces of wood out of rectangular ones. And a couple of extra cylindrical ones for good measure.

Cutting a bore.

Bores all done and a few trials through the whole set of operations.

Exterior Z-axis only profiling on the lathe.

Sanding before the last machining operation. The shop vac is my friend.

The final program for the exterior profile to be cut in the last operation. I love this kind of accidental design - geometry derived from the interaction of part shape, the tool engagement rules and the CAM algorithm.

The last cutting operation. Just final detail sanding left.

The process from start to finish: stock, back bore, front bore, exterior Z-axis profile, exterior X-Y profile, detail sanding and oil.
