Lathes etc and tooling

On or around Mon, 24 Mar 2008 15:41:00 +0000 (GMT), Donald enlightened us thusly:

HSS is fine until you want to do something a bit more demanding, like I did the other day:

The throttle pot. on the LDV is held on by approx 7mm nuts which hide down little holes and are impossible to get a spanner on. Even the deep

OK, if I'd not had TCT I could have annealed the socket, turned it, then re-hardened and tempered it, but that would have been a lot more hassle.

Not being into CNC myself, it would appear that it is ideal for very complex projects where accuracy in several planes iscritical. Also you need to remeber that some types of projects now being tackled by 'amateurs' would have been difficult even for professional set-ups only a few years back (e.g. machining jet turbine compressors and the like).

As far as tooling is concerned, I still have my doubts with tipped tooling for general work. When I last used lathes etc I was still a relative 'youth', returning to it some years later as a hobby - I thought that all the new 'gizmos' on the market would be the be-all & end all! Whilst fine for very tough/difficult materials thes finish of many of these tipped tools often leaves much to be desired. A really sharp, correctly ground HSS bit is a pleasure to cut with (it looks right and sounds right), and the finish is clean. The 'cost' of periodically honing or re-grinding is pretty insignificant in a hobby environment. So I must admit that the tipped stuff tends to be used for roughing work, and HSS for 'finishing'. In fact I have just finished building Harold Hall's design of tool grinding table (as featured ion his book & in MEW many issues back) - it's cetainly imroved my grinding accuracy! If it's a hobby - it should be just that, it should give you pleasure in the performance. Industrial tooling is designed for rapid metal removal, minimal tool wear, and an acceptable finish - each tool being closely specified for the individual job in hand - but all invariably used on high power, fast-feeding industrial machines. Mike

Just some observations on CNC.

The main one being that it is now completely affordable, a few years ago it was still in the realms of industry, big money, long runs and payback.

My big CNC cost £24,000 of which about £15,000 of that was the controller and associated electronics. This could now be replaced with a £80 program and £ 500 worth of electronics.

On a smaller scale we are seeing people building router type machines from MDF board, studding and drawer slides. Don't laugh they work and they teach people a lot, good and bad. They then use these machines to make an improved MKII.

It's now got to the point where for some CNC has become their hobby Regards,

John Stevenson L Stevenson [ Engineers ]

As opposed to just simply buying tools as a hobby?

Charles

Is there anything wrong with rebuilding machine tools as a hobby?

:-)

Mark Rand RTFM

Well, it's kept me out of the pub for quite a few years, so maybe there IS something wrong with it

AWEM