Lathes etc and tooling

Things have changed since I bought my ML7 in the early 1960's for £120. There are now enquiries about CNC machines and fancy insert tipped tools. Maybe I don't know what I am talking about but I thought that CNC machines were for repetition work and tipped tools were for use in high speed production lathes. In a fit of nostalgia I bought a Portass S lathe which was advertised about ten years or so ago. £110 if my memory serves me right. This is a somewhat primitive machine by any standard but it produces accurate results. I use this lathe a lot and it has more than earned its price in jobs I have done for local fishermen. At some stage I built a Dore Westbury milling machine, another exercise which was well worthwhile because it taught me a lot of things including using the 4 jaw chuck for accurate work. Ian Laws instructions were an education in themselves. Coming back to tooling, I admit to buying tipped and insert tipped tools and have not profited by this. My advice, for what it is worth is to stick to HSS It is reasonably cheap and does the job.

Donald, South Uist

Reply to
Donald
Loading thread data ...

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

1/4"square drive socket wouldn't fit, so in the lathe it went and was turned down to a very-thin-wall, which did the job. No HSS tool would have turned that down, but the TCT one did.

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.

Reply to
Austin Shackles

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

Reply to
MikeH_QB

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 ]

Reply to
John Stevenson

As opposed to just simply buying tools as a hobby?

Charles

Reply to
Charles Ping

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

:-)

Mark Rand RTFM

Reply to
Mark Rand

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

AWEM

Reply to
Andrew Mawson

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.