Actually they were made using a thread cutting lathe that had a precisely made chain instead of a lead screw, I've actually seen such a machine in use. It would be interesting to know how some of the other chicken and egg situations were solved though, any have any links ?
I'm sorry but joining a chopped off bit of the original to a new bit is a botch to me and would be a last resort in my book, others may have different standards 8-).
Actually I did buy several bits from Ebay, a vertical slide and vice for example, but didn't want to wait until a lead screw came up so paid the extra to get going. Please don't take offence, your advice is appreciated.
Unfortunately I do have to earn a living so I count my free time as a precious comodity and may well make different judgements to others, roll on retirement 8-)
Maybe the word 'everything' was a bit strong, but most things certainly. Take the latest power tools, I bough a B&D hammer drill and it just burnt out with normal use, on the other hand I have a very old B&D drill in a metal case that is still going strong. Is the latest Chinese lathe any more accurate than my 30 year old Boxford with an unused P&B chuck?, I doubt it. Of course I'm comparing with my farther's day, not my grand father's.
What has changed is that you can get engineering stuff from China, Poland etc that are of adequate quality yet a fraction of the cost they were a few years ago.
Greg