What has been the Single Biggest Advance in Machining Technology in the last 50 Years

[flick]

If one of you old-timers who have actually been there wouldn't mind informing a young gaffer like myself... are tracer lathes capable of square shoulders? The information I was given while apprenticing indicate that a hydraulic tracer needle is incapable of executing a 90 degree (x only) movement. Were there any models made that could work around this (perhaps with a secondary, angled needle?), or is it just considered a limitation of the technology?

[RICHARD ZASTROW]

flick, a 90 deg. cut to a shoulder and face can be made with a 2-axis tracer or with an auxiliary slide similar to a cut-off slide on a screw machine. "google" Mimik and/or Trace-o -matic etc. Mimik has online videos of tracing but don't show enough to answer your question.

Snoop around "tracer lathe's".

I s'pose it's a matter of volume and justification. The app. I referred to had a half dozen surplus tracing lathes they had used before changing to CNC lathes. They left a set-up in each of the lathes so there was no set-up expense. One man could run them all, they weren't all that fast.

Dick Z

[tobyaxis]

Originally Posted by Geof I have no idea if hydraulic copy lathes are still in use but with modern tooling these could be as fast or faster than a CNC. I wonder if it would be viable to have a CNC machine to make the templates which then went onto hydraulic copiers for production.

I think a friend of mine has a copy Lathe or Mill in the back of his shop. This is a good idea Geof.

[handlewanker]

Huh? Who in his right mind wears belt and braces.

The whole beauty of the CNC set up is to deskill the operation, and if you have to employ highly skilled setters to manage copy lathes you are back in the stone age.

Maybe some parts can come out a bit ahead of the pure CNC setup, I can't comment on that scenario, maybe anyone that is into this area can be more informative.

Many, if not all, of the mass produce areas are now working "just in time" or to order, that is it don't get made if it aint ordered, so stock items aren't made to stock levels which eliminates the dead dollar bank that the part stores represented years ago.

The last firm I worked for in the late 90's had a part store that held 10 million dollars worth of stock, which never went down due to the stock level control that existed at the time.

After they had the consultants in and 60% of the workforce, from top management to tea lady, all the tool room and most of the production machinery, got trimmed back, the stock levels were work in progress on the shop floor and a small emergency stock of some outsourced parts.

There will always be a situation whereby even the most sophisticated work process cannot compete, but that is academic and horses for courses apply.

Back to the CNC/copy lathe scenario, if I were running parts to order, there's no way I'd be having a copy lathe sitting idle while the orders are coming in, whereas a CNC can make one off's as and when the button gets pushed by the lad fresh out of school with some training in button pushing, also you would be mad to allow an unskilled person near a copy lathe to make adjustments.
Ian.

[RICHARD ZASTROW]

Ian, The scenario I mentioned never changed the set-up on the tracer lathes. So There was no "highly skilled or highly paid setter" All lathe operators in the shop were very capable in setting up and operating all the lathes. I guess that's old fashioned now.

As far as JIT, I interpret it differently. Jumbo Inventory Transfer from the big outsourcing guy to the little contract supplier guy.

I dealt with that for years. The big guy required we buy castings from their approved foundry. The foundry had minimum order quantities much larger than the number of parts ordered by the big guy. So big guy had no money in dead inventory and we delivered directly to big guys assembly line.

We didn't get paid till after the part was assembled and probably shipped and we still had an inventory of castings (for which we had already paid).

I could tell you many more of these "war stories" but what will it change? Probably doesn't matter any more since most of that work is no longer machined in "western companies".

There, I feel better now. LOL

Dick Z

[mozmozmoz]

I'd vote for the advances in materials technology. In the olden days we had to carve our machines out of big chunks of dodgy steel because just couldn't be sure what we were actually working with. Asking for 4 or 5 significant figures of alloying and precise heat treatment was just wishful thinking, let alone the absence of impurities and discontinuities that we take for granted today. So today our off-the-shelf tools weigh much less, are more rigid and are built far more precisely than they could have been built in the 1970s by anyone, at any price. This makes more difference than you might think - if the cutting tool weighs half as much, the 3-axis head it's attached to can be half the sectional area and 1/10th the mass and then if the motor is also 1/4 the weight, the moving mass drops again so everything else gets smaller and the machine acceleration and hence overall job speed goes way up.

Downstream, that means that I can buy a cheap tool made with that gear much more readily than before (and in fact the whole DIY CNC market comes from that).

Admittedly I'm torn because advances in computer power help (my laptop can do 3D rendering while also running a 3D CAD program), as do related advances in power electronics (20 years ago we had to go analogue and discrete component much earlier in the drive controls just to get the speed and power we needed... these days it's straight from the chip to the 10A power transistor at 20kHz).

[jlanelines]

If you wanted to check out something really odd, Firth Sterling made a material that they called cast carbide. It was used in roll turning, but they stopped making it because of the cost. I worked for Firth years ago. I had several customers who begged for the stuff. Never really knew much about it. They stopped selling it before my time.

I know all about KC850. I worked for two major tool companies. I could beat it in some specific applications, but never as a shop-wide grade. It was amazing.