Thread: Parting off problem

From what Edd said, I think, at least part of my problem, was I was running the lathe too slowly. I had it on about 400 RPM, I think. It seemed to machine ok at this speed, except for the posted problem I had ( if that makes sense...)
When I did my apprenticeship, many moons ago I learn't the importance of using the right speeds and will have to relearn that, I think. Here's a couple of pics anyway.

Originally Posted by Sterob

From what Edd said, I think, at least part of my problem, was I was running the lathe too slowly. I had it on about 400 RPM, I think. It seemed to machine ok at this speed, except for the posted problem I had ( if that makes sense...)
When I did my apprenticeship, many moons ago I learn't the importance of using the right speeds and will have to relearn that, I think. Here's a couple of pics anyway.

Thats a fairly solid looking parting tool .
Another point to remember is that as you are parting off the diameter of what you are cutting is decreasing ,it dosent hurt to stop the lathe now and then and increase the speed.

Originally Posted by Article99

Sorry, carbide tips? LOL. Think more along the lines of extrusion dies, step drills, profile cutters etc. We actually supply the aircraft industry, too. Quite fun making profile tools for those guys. Max of 2 micron runout and 3 micron diameter tolerances plus the actual profile itself. C?*ty stuff.

That said, I will take a moment and apologise. If you're a grinder, you'll know where I'm coming from when I say the majority of tradesmen in Aus aren't craftsman at heart anymore. It's all done on an NC lathe at a million miles an hour, plus minus 100 micron.

Myself, I spend the majority of my time on a cylindrical or a tool and cutter. The lathe and mill are really only there for making jigs and doing foreigners.

Don't really like the idea of boring gun barrels for an assault rifle thats gonna get used at less than 300 yards. Just not the same calibre (lol) as what I do now.

Anyways, matey, thanks for clearing up your own background and correcting me in the same hit. Had you figured for a run of the mill fitter & f*cker doing the odd bits and pieces in some maintenance depo. Glad to know it isn't the case.

Peace.

Not much call for tool and cutter operators out side of tool rooms I guess.

But in the maintenance side of the trade ,plenty of opportunity for
Fitters and Turners who use lathes , shapers and milling machines vertical borers etc.
Finished my trade in the early 70's ,spent some time in the toolroom , but found it as exciting as watching paint dry .
Moved over to the maintenance side of the company and spent many hours making replacement parts for their production machinery ,and for toolroom machines.
Some of the jobs we did involved cutting large square threads ,buttress threads ,
single throw crank shafts for Hiene C presses.Hundreds of bronze clutch bushes for Forwood Down production presses
Also poured white metal bearings ,machined and hand scraped them for fitting.
Have also hand scraped lathe and milling machine ways while restoring some tool room machinery to be put back to work.
Restoration work involved making new gears (Helical and straight cut) for the milling machine gearbox and flame hardening the teeth.
Thats the machining side , then there is Hydraulics and pnuematic systems that have to be diagnosed and repaired.Just about every machine these days from toolrom NC machinery to mining equipment has some form of hydraulic or pnematic sytem in its design

If I had to go back to my trade I know what Id rather be doing I'll stick with being a Fitter and f*ker thanks.

Originally Posted by Article99

Today I dismantled and serviced the work head spindle on an old J&S Cylindrical.

The first year of my apprenticeship was spent at TAFE learning the practcal side of four trades

Machining - Welding - Sheetmetal Work - Electricity

Although 50% of it was spent doing the machining whilst the other three were squeezed into the remaining 50%. I have very fond memories of that time with 130 lads (no girls) just out of school and learning what life was about.

One of the teachers their had worked at Jones and Shipman previously making up the various types of machines. He told us that they had a roster within the toolroom for one of the guys to come in an hour before the set starting time in order to switch on all the grinding machines so they would be up to working temperture by the time the other guys were due to start working.


In my class of 60 at Swinburne, I'm one of only two there. All the other lads are pretty much just maintenance.

Well in my day only NC machines were the go and we only had one of those. Consequently I think when CNC machines came in so the numbers of toolmakers and operators decreased - mechanisation.

Here's hoping you have a great weekend too and we've got another twenty posts of angry woodies to have fun with.


... Nearly forgot. We've still gotta get Sterobs parting tool working for him. Hey sterob, if you're still tuned in, can you take a few pics of your setup, mate?

Pretty standard practice for grinders, I think. They move around way too much when they're cold. I arc up the cylindricals and surface grinders at about huppast five in the morning. By about 7 or so they settle down quite nicely. Only time the spindle gets shut down is if you need to change wheels or if it's knockoff time.

Strange with the CNC age. Yes, they can spit out work rather quickly and have one person put out the work normally done by three rather easily, but they're not THAT good. There's still gotta be a meatbag standing next to it taking measurements and making sure the thing stays on size. For jobbing or low production run type work, I find they're really only good for doing profiles and such where it works out quicker than doing them on a manual grinder. About the only exception to that rule is the NC tool and cutter. Makes pretty light work of carbide. (But then again it's a sealed machine that floods the job with high pressure cutting oil, rather than a dribble of water, so it'd want to grind quickly.)