Question on chucks & a warning on lathe safety.

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Question on chucks & a warning on lathe safety.

This topic has 30 replies, 19 voices, and was last updated 11 February 2017 at 13:10 by Nick Hulme.

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9 February 2017 at 16:30 #283341
MW
Participant
@mw27036
Hi,

Bit of an armchairneering/ ends and oddments kind of post, but..

Heres a silly question that occurred to me today, why, when people frequently paint castings/metal slides for lathes and machines, do they not consider painting their chucks as well?

Are they prone to damage? They certainly rust. (painting could look awful on a chuck if it wasn't done properly). Just an interesting idea, but I've never seen anyone do it.

I read this story today about a man who died a couple of years ago as a result of trying to machine a piece of stainless pipe that threw itself off the lathe, machining tube is certainly to be done with caution and everything properly secured, fixed steady or tailstock centre comes to mind..

He was only rubbing it down or cleaning up the outside of it, albeit unsecured on one end. (1.5M long!) so it was definitely a big lathe.

**LINK**

A tragedy for him and his relatives but also another reminder to us to be careful about what we try, I know some of us have big machines but we can get over familiar with our equipment and it leads to this potentially. The force that threw it out was enough to pierce his skull and brain.

Stay safe..

P.S, I actually avoid machining pipe if possible due to how unpredictable it can be.

Michael W

Edited By Michael-w on 09/02/2017 16:36:26
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9 February 2017 at 16:30 #34854
MW
Participant
@mw27036
9 February 2017 at 16:51 #283345
Ian Parkin
Participant
@ianparkin39383
Whilst a certain tragedy for the chap it sounds like an accident was inevitable a 4ft tube sticking out the chuck unsupported and only in the chuck 1.5 inch
9 February 2017 at 17:14 #283350
I.M. OUTAHERE
Participant
@i-m-outahere
Sometimes i use the surfaces of the chuck as reference points or to set the toolpost square to the centre line of the lathe for parting and painting would make this impossible besides the fact it would look UGLY !

Ian
9 February 2017 at 17:23 #283352
Martin 100
Participant
@martin100
Lots of hazards operating and working around machinery. We've all probably at some time had bits come loose in the chuck, tools dig in and shatter, dropped chucks etc resulting in bad language, cuts, blood blisters and bruises, some like the case above have sadly come off far worse.

One quite prominent youtuber who really should know better was recently observed using scotchbrite to clean up a part with obvious ragged edges maybe 1/4" further in the recess from the internal diameter he was cleaning up. Something you might get away with on the bench. In a lathe, under power, and using your finger to poke the scotchbrite into the hole then its just the luck of the draw as to what happens next. The bloke was totally oblivious to the hazards and actively displaying this method of working as part of his skills without even a slightest inkling that someone else might try and copy his method of working and not be so lucky.

P.S. Within limits a rusty chuck body clearly works just as well as a non-rusty one. The bits that matter are oiled or greased.
9 February 2017 at 17:27 #283353
Hacksaw
Participant
@hacksaw
That "Industrial lathe accident " on youtube gives me the willies !!
9 February 2017 at 17:59 #283355
Nick_G
Participant
@nick_g
.

I would not consider painting a chuck for the reason given by XD 351. i.e. it's a valuable ref point and would look as ugly as naked fat bird sat on a stool. – It would also chip and wear off quicker than you can cook a pancake making it look even worse.

I find the best way to keep a machine free of rust is to use it.!

As for 4ft sticking out of a chuck unsupported. It was never going to end well now was it. …………. Very 'Darwinian' IMHO

Nick
9 February 2017 at 18:21 #283361
MW
Participant
@mw27036
Posted by Nick_G on 09/02/2017 17:59:36:

.it's a valuable ref point and would look as ugly as naked fat bird sat on a stool. – It would also chip and wear off quicker than you can cook a pancake making it look even worse.

Nick

Ah well, you never know Nick. Some of us may be quite partial to that.

I used to use a leather faced, and copper mallet to knock the cam-lock chucks off the big boy lathes onto a wooden cradle. I guess with the size of it and the rather seizing fit that took hold on the recess, you could say unless you were the hulk it was totally necessary to hit the chuck in order to do the job. In that case, no question it would chip.

But for the more dainty chucks, what situation occurs, other than handling, where you need to smack your chuck? Unless you're hitting it under power, which is obviously bad practice. Is there any reason why it should be damaged provided you're using it properly. There is the chuck key that could cause wear but unless you have a really bad aim, you wont be hitting the chuck body.

I would agree, this certainly warrants a better quality of paint than your regular brands, but I think it could look good if you used a hard wearing glassy coat of enamel.

I say again, is a rusting surface, shouldn't be struck(provided you aren't covered under the aforementioned handling and fitting procedures of big lathes), It could look good? Theres potential reasoning there, I give it that much.

Michael W
9 February 2017 at 18:24 #283362
MW
Participant
@mw27036
I should add I have an eternal fight trying to keep my four jaw from rusting using a variety of different preservatives, I haven't found one that's worked for more than a week yet.

My three jaw I can just about manage to keep the rust at bay, despite a few flecks occurring now and again. But with the four jaw it ravages it like a monster. Anyone tried a varnish?

If it looked as smooth and shiny as say, a new car, tell me you'd not be at least be tempted?

Michael W

Edited By Michael-w on 09/02/2017 18:27:58
9 February 2017 at 18:28 #283364
Rick Kirkland 1
Participant
@rickkirkland1
Forget paint, , chucks would look beautiful Blued. And rust resistant. T I C posting, , let's not have the pedantic posters go getting uptight.
9 February 2017 at 18:42 #283370
not done it yet
Participant
@notdoneityet
That "Industrial lathe accident " on youtube gives me the willies !!

I've watched that before. Nothing really to do with pipe. His loose clothing rippied off him. He was lucky it was a pipe, perhaps, or he could have been going round with the chuck and pipe!
9 February 2017 at 18:45 #283376
Roger Williams 2
Participant
@rogerwilliams2
Its quite possible he only intended doing this at a very low RPM, still daft I know, and perhaps forgot that it was in high range…….

Referring to the fatal accident at the beginning.

Edited By Roger Williams 2 on 09/02/2017 18:49:44
9 February 2017 at 18:53 #283378
MW
Participant
@mw27036
Well back on topic number two,

The coroner said (not a machinist I know) that he appeared to believe that what he was doing would be safe. It sounds like a big lug or fabrication was welded to the pipe. The piece was gripped 40mm deep on the lug end with the open tube facing downwards towards the tail end. So he believed that this would be adequate to support it.

To be honest, given how long it is, it doesn't sound like this was an operation he'd done before. Because at 1.5M, i'd imagine the runout would be horrendous.

I would've atleast used a fixed steady on this setup if it were available. However, i'm not going to go judging or condemning him as hindsight is a wonderful thing and i'm not closely involved with what happened.

But it did scare me slightly. As I have had a piece of much shorter copper tube come off the lathe in the past. And that did have a steady. I'm still in one piece obviously but it hit the roof of my shed. And was bent inwards by quite a margin.

Michael W

Edited By Michael-w on 09/02/2017 18:54:57
9 February 2017 at 18:55 #283379
daveb
Participant
@daveb17630
I treat bare iron and steel surfaces with beeswax furniture polish, works well on chucks, handles and handwheels. Dave.
9 February 2017 at 18:59 #283380
MW
Participant
@mw27036
Posted by daveb on 09/02/2017 18:55:33:

I treat bare iron and steel surfaces with beeswax furniture polish, works well on chucks, handles and handwheels. Dave.

Good to know, I might try that. I have some carnuba wax that may give a similar sealing effect.

Michael W
9 February 2017 at 19:29 #283389
Nick_G
Participant
@nick_g
Posted by Michael-w on 09/02/2017 18:21:14:

Is there any reason why it should be damaged provided you're using it properly.

Michael W

.

Swarf.. ………… You know that sharp abrasive by product you get from a lathe when you use it.

Nick
9 February 2017 at 19:37 #283391
JasonB
Moderator
@jasonb
Do you never tap a machined side of a piece of work back against the chuck face so it sits true to then machine the other side?

Or I often put a couple of parallels against the chuck face and push the work up against that to again set the machined face true.

Can't see that working once you have slapped a thick uneven coat of glossy enamel onto it.

I find that keeping chucks in te cabinet under the lateh does not help with rusting as they stay cold and any moisture in the workshop as it warms up such as your breath or from cutting fluid will condense out on teh cold metal.

J
9 February 2017 at 20:05 #283397
MW
Participant
@mw27036
Posted by JasonB on 09/02/2017 19:37:52:

Do you never tap a machined side of a piece of work back against the chuck face so it sits true to then machine the other side?

Or I often put a couple of parallels against the chuck face and push the work up against that to again set the machined face true.

Can't see that working once you have slapped a thick uneven coat of glossy enamel onto it.

J(asonB)

You got me JasonB, I admit defeat.

I do use parallels occasionally on the chuck face.

I guess i'll just have to do with rusty old iron.

Michael W
9 February 2017 at 20:11 #283399
vintagengineer
Participant
@vintagengineer
With regard to the lathe accident I was always taught to always put a centre in, if the amount sticking out exceeds the amount being held. Even when you are facing the material!
9 February 2017 at 20:22 #283401
not done it yet
Participant
@notdoneityet
any moisture in the workshop as it warms up such as your breath or from cutting fluid will condense out on teh cold metal.

That is why I have installed a small dehumidifier in my small partitioned-off and insulated workshop area. Just works a few hours at night on E7, but warms and dries it sufficiently to avoid condensation. Probably need air con in the summer!

Re painting – no item that may show signs of failure (before actually failing, hopefully) should be surface coated with paint. This is apart from the aethsetics and practical problems of alignment with other parts. Blueing or blacking would be acceptable, but expensive – and eventually wear in places. I know I would not operate a chuck if there were any signs of cracks developing.
9 February 2017 at 20:31 #283406
peak4
Participant
@peak4
Re. Rust proofing, not tried using it on chucks, but Motorex 645 aerosol works well on the various bikes.

I'm still using old stock, but I believe This Is The Same Stuff, just renamed.
9 February 2017 at 21:06 #283413
I.M. OUTAHERE
Participant
@i-m-outahere
A chemically blued chuck – now that would look cool !

I use lanotec ( usual disclaimer applies ) on my machines a wipe over with some paper towel sprayed with this stuff works well , in winter i have seen my larger lathe (hafco AL320 ) litterally dripping with condensation but strangely my smaller lathes don't seem to suffer as bad .

In winter time if i won't be using that lathe often i paint the lanotec on with a brush and let it dry , i still get the same condensation but the lanotec leaves a wax like coating that keeps the moisture off the metal surfaces .

I also purchased a heap of those rechargeable moisture traps off ebay and if i use a plastic tarp to cover the machine it forms a sort of seal and the moisture traps suck out any moisture in the air and i no longer end up with a dripping wet machine .

I haven't tried carnuba wax but i see no reason why it would not work , same goes for a block of lanolin – never seen a rusty sheep !

I also picked up some deoderised fish oil to try but haven't got around to yet , this winter coming i might set up some test pieces out in the yard and try some different coatings to see what works best .

Ian.

Edited By XD 351 on 09/02/2017 21:12:28
10 February 2017 at 00:12 #283428
Nick_G
Participant
@nick_g
Posted by Michael-w on 09/02/2017 20:05:30:

I guess i'll just have to do with rusty old iron.

Michael W

.

Probably best.

As next time you set fire to your plastic swarf it would at best ruin the beautiful Bentley standard chuck paint finish or at worst end up as a remake of the 70's film 'Towering Inferno'

Nick
10 February 2017 at 01:32 #283432
Hopper
Participant
@hopper
I saw a similar accident when a first year apprentice in the training centre held a four-foot or so piece of 5/16" BMS in the chuck of one of the Hercus (South Bend clone) lathes. He was machining a couple of pins for a stud clamp apprentice projects off one end while the other was stuck 3. foot out the back of the spindle. We had stands made for this exact purpose, a tripod with 2" diameter pipe on top turned sideways to stick long jobs through, bet he failed to use it. Mid-job the spinning piece of bar bent at 90 degrees right at the far end of the lathe spindle, leaving the 3 foot or so whipping around in a large circle at 1,000rpm or so. It was very exciting and just dumb good luck that nobody got hurt, seriously.

Sounds like the accident in the OP link was the usual combination of two or more causes, one he used no fixed steady, and two "one of the chuck jaws tightened on the hole in the end of the tube" whatever that means. It sounds like some reporter's misinterpretation of he gripped the pipe between two of the three chuck jaws with a small gap between job and the third jaw, as is easy enough to do with an awkward job. When it cam loose, with a welded on braket adding weight to the far end, it kicked sideways and swung like a club hammer. Tragic.
10 February 2017 at 09:30 #283457
Carl Wilson 4
Participant
@carlwilson4
Was that the apprentices fault? No it was not. A case of a lack of adequate supervision.
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