It's interesting to get more precise and accurate machines out of the ones came before.
These days, if you want to get milling and grinding down to 1 micron without lapping using only your own expertise and some parts from eBay (air bearings and precision-ground slabs):
It wasn't nearly so easy. Dan hand-scraped in several surfaces on the lathe; for example the headstock, to get the axis parallel to the ways, and so on.
These days, if you want to get milling and grinding down to 1 micron without lapping using only your own expertise and some parts from eBay (air bearings and precision-ground slabs):
https://youtu.be/sFrVdoOhu1Q
The creator (Dan Gelbart) demonstrates nitrogen-tight parts without bearings, and claims zero wear or lubrication needs.
#AvEclub