Getting pretty close to having enough footage to put together Part 4 of the video series - that will be about machining the knee. The rough cast surfaces were milled off, taking care to make sure the two adjacent surfaces that would receive female dovetails, were perfectly square to one another. For each dovetail, I removed most the waste using an end mill, then used the dovetail cutter. The dovetails need to be oversized to accomodate 3/32" thick gib strips. I ended up with a really nice fit that is quite snug but will move with a little force. Once the surfaces are scraped in, it should be perfect. I can already see, from the bright spots left on the rough machined bearing surfaces, that scraping will go quickly... the high spots are already very uniformly placed. I just need to drill and tap the gib screw holes for the column gib, then I'll be ready to start editing the next video.
In the meantime, here are some more photos.
After milling the dovetails for the column, test fit with the gib strip stock in place:
Set back up in the mill, and slotted out ready for the bed dovetails:
Both dovetails cut:
Fit together after making a gib of the proper length, a snug enough fit that the knee stays put: