I found this on adopter Newsgroup.
I took in a Machining and Manufacturing expo yesterday. The large exposition hall at State Fair Park was filled with displays ranging from 10' x 12' booths with little more than a placard announcing the company name and a smiling representative, eagerly asking everyone who passed-by, "Do you use any (whatever his firm produced) in your business?" to huge displays of massive CNC machine tools, under power and busily reducing slabs of metal into flying chips.
The most intriguing thing I saw however, was a four cylinder DOHC engine which had been machined completely from billet. It was a capability demonstration project that Mazak Machine Tool Company had created. The crankcase, head, crankshaft, camshafts, rods, pistons and associate parts were all carved-out of aluminium or steel blocks. The combustion chamber layout wasn't up to current design practices (it had a 90 degree included angle between the valves and a full hemispherical chamber with a pent-roof piston) but it sure was cute and a great demonstration of the capabilities of their machines. For example, the crankcase was machined on a lathe, rather than a machining center. By holding the billet on each end in chucks on opposing spindles, the details could be machined by side-acting milling or drilling tools. The advantage is that ALL of the machining was performed in a single set-up. Even if done on a milling machining center with a 5th and 6th axis, you'd have to do a couple of set-ups to machine all the surfaces.
Wow! Ain't computers neat? This sort of stuff would be completely impractical without a bunch of silicon chips doing the jillions of calculations it takes to describe the tool movements necessary to whittle-out such complex shapes.
-Gary-
Thought you'd like it!
Regards,
Kim Siddorn
I'd rather have a free bottle in front of me than a free frontal lobotomy!