The Bolton 9 triple expansion steam engine has 6 eccentric cams which drive the steam valves, 3 forward and 3 reverse.
The cams are each made as a split, offset disc. The disc is machined after 2 pieces of brass are soldered together (soddered if you are north American), then the solder is melted so the eccentric discs can be attached to the crankshaft.
I spent a day machining the brass pieces and soldering it, and turning the discs.
Today I spent a couple of hours setting up the threaded holes to joins the disc pieces after the solder is melted away.
In the process of doing this I hit a wrong button, and fu**ed the whole job. So I turned off everything in disgust, and spent the remainder of the day cleaning up my Quorn tool and cutter grinder, in preparation for an exhibition next weekend.
Sh*t happens when metalworking. At least it will be quicker when I repeat this exercise in a day or two, if I can learn from the mistakes.