Lathe shocks

[Ian S CParticipant @iansc]

An alterative to changing the male plug, get a bit of lead with a plug moulded on (if there's a female plug on the other end, cut it off), remove the existing cord from the lathe and wire in the new one, make sure of a good earth connection, and earth the lathe and metal stand and motor.

Ian S C

[Michael GilliganParticipant @michaelgilligan61133]

Thanks, Neil … But:

My observation [as quoted by John S] was perfectly straightforward. … I was simply reciting what I believe to be Nitai's position on this.

Various posters have told him to cut off the existing plug and replace it with the local type; but he would clearly prefer not to do so.

I have made absolutely no suggestion that there is anything "not fit for purpose" about the manufacture of lathe [and I therefore resent John's capricious insinuation]. … The fact is simply that it was supplied [by someone] with a European style plug, and Nitai has Israeli sockets.

MichaelG.

[AjohnwParticipant @ajohnw51620]

Posted by John Stevenson on 05/08/2015 10:12:09:

Posted by Michael Gilligan on 04/08/2015 17:03:52:

Getting [and fitting] "the proper plug" would involve removing the moulded-on original plug [with its advantages of originality and engineering superiority].

MichaelG.

.

If he can't sort it safely either by skill or paying someone who has then it needs to go back in the box and stop playing with it – simple.

True – perhaps there is need for another law – people can't sell things that aren't fit for use. There already is one so no need. The shop should either sort out the correct plug or supply an approved adapter. That is the route I would follow even though I can change a plug and even get the stripped wire lengths etc correct even arranging for live to pull out 1st if some one does something silly with the lead.

Clearly we all need to buy a PAT tester and become qualified to use it rather quickly but fortunately there is still a little bit of sanity in this area. It is likely to slowly vanish though. If people do have to play with the mains – sockets etc neon test screwdrivers are available. I have found miss wired sockets also ones with too much bare wire in both plugs and sockets. This is why health and safety marches on. More so at work because companies have done things which do kill people and or seriously limit their life span. Hence the need for more stringent requirements there. In general their main interest is profit.

John

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[korbyParticipant @korby]

In 1959 my father bought a new ml7, unlike chinese stuff it worked straight out of the box as they say everthing was spot on .he used it mainly to make bits for motor bikes and cars. But every so often would get a bit of a shock. Traced it to static on the primary drive belt fixed by rubbing carbon dust on the belt.

Well dad went to the great workshop in the sky many years ago but the m,yford is still going strong

Who was it who said quality remains when the price is long forgotten.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by korby on 17/08/2015 20:38:14:

Who was it who said quality remains when the price is long forgotten.

.

John Ruskin.

MichaelG.

[Ian PParticipant @ianp]

Posted by korby on 17/08/2015 20:38:14:

In 1959 my father bought a new ml7, unlike chinese stuff it worked straight out of the box as they say everthing was spot on .he used it mainly to make bits for motor bikes and cars. But every so often would get a bit of a shock. Traced it to static on the primary drive belt fixed by rubbing carbon dust on the belt.

Well dad went to the great workshop in the sky many years ago but the m,yford is still going strong

Who was it who said quality remains when the price is long forgotten.

I would have thought that Myford lathes in the 50s would have had metal pulleys clamped to metal shafts carried in metal bearings which in turn would be in metal castings bolted to the lathe and cabinet which I would expect to be earthed. I fail to see how static can build up in that situation but I'm prepared to learn.

Ian P

[John Stevenson 1Participant @johnstevenson1]

Well I don't know how it worked out of the box as they were sold with no motors and chucks in those days.

Bought two so I do know.

It was up to the owner to put them together and wire them up.

[Neil WyattModerator @neilwyatt]

Posted by Ian Phillips on 17/08/2015 20:59:10:

Posted by korby on 17/08/2015 20:38:14:

In 1959 my father bought a new ml7, unlike chinese stuff it worked straight out of the box as they say everthing was spot on .he used it mainly to make bits for motor bikes and cars. But every so often would get a bit of a shock. Traced it to static on the primary drive belt fixed by rubbing carbon dust on the belt.

Well dad went to the great workshop in the sky many years ago but the m,yford is still going strong

Who was it who said quality remains when the price is long forgotten.

I would have thought that Myford lathes in the 50s would have had metal pulleys clamped to metal shafts carried in metal bearings which in turn would be in metal castings bolted to the lathe and cabinet which I would expect to be earthed. I fail to see how static can build up in that situation but I'm prepared to learn.

Ian P

In the 50s most people would be buying a lathe without a motor and fitting their own. If the motor was a fraction of a horsepower they may well have been running it of an unearthed 5 or even 2 amp plug – my Dad still found a market for these in the early 70s. As I recall all his soldering irons had 2A plugs with 'split pin' connections. I'm sure some folks would even have tried running a lathe off of a light fitting.

Neil

Neil

[Neil WyattModerator @neilwyatt]

Posted by Michael Gilligan on 17/08/2015 20:51:47:

Posted by korby on 17/08/2015 20:38:14:

Who was it who said quality remains when the price is long forgotten.

.

John Ruskin.

MichaelG.

Henry Royce.

Ruskin may possibly have said something similar…

**LINK**

Neil

[Ian PParticipant @ianp]

Must admit I did not think of that, (motor and lathe bolted to wooden bench separately). There would have been no need to earth the lathe so I can see how static might have developed.

In about 1960 I used to stand and drool (lust) over the Myford lathes in my local toolshop in the high street, I am sure some were complete on steel cabinets. Compared to the then current opposition Myfords looked really modern and streamlined.

Ian P

[Martin CottrellParticipant @martincottrell21329]

Posted by Neil Wyatt on 05/08/2015 10:45:59:

I'm more concerned that a single statistic is being used to prove we should adopt industrial working practice in our home workshops.

I'd better go and check the PUWER sheet for each of my appliances is up to date, I'm sure John does this regularly.

Neil

An interesting point Neil but I think in this case the OP has taken this problem out of the privacy of his own workshop and placed it firmly in the public domain and asked for advice. The experts, whose opinions he sought, have determined that the machine is not properly earthed due to an incompatible plug/socket combination & have suggested he replaces the plug with correct one or gets an electrician to fit one if he does not feel competent to do so himself. To me this seems like a common sense solution, very easy to get resolved, which will render the lathe safe to use from an electrical point of view. In my opinion this is not a case of ""adopting industrial working practice in our home workshops" just the adoption of plain common sense. As to John McNamara's statistic to which I assume you are referring, it seems to me that however you might wish to interpret it, it shows that electricity can issue the ultimate punishment to those who don't treat it with due respect!

What I find more concerning is the fact that the OP has asked for advice as to why he is receiving electric shocks from his lathe then choses to disregard the advice of experts and rig up his own , arguably equally unsafe, solution. Sometimes I think you can bang the H&S drum as hard as you like but what some people really need the most is protecting from themselves!

Regards Martin.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Neil Wyatt on 17/08/2015 22:16:07:

Henry Royce.

Ruskin may possibly have said something similar…

**LINK**

Neil

.

You win, Neil

I accept that Royce's [quoted] words are closer to korby's version than are Ruskin's.

MichaelG.

[Neil WyattModerator @neilwyatt]

Posted by Martin Cottrell on 17/08/2015 22:31:23:

Posted by Neil Wyatt on 05/08/2015 10:45:59:

I'm more concerned that a single statistic is being used to prove we should adopt industrial working practice in our home workshops.

I'd better go and check the PUWER sheet for each of my appliances is up to date, I'm sure John does this regularly.

Neil

An interesting point Neil but I think in this case the OP has taken this problem out of the privacy of his own workshop and placed it firmly in the public domain and asked for advice.

That comment was a specific reaction to the suggestion that we should follow safe working practices at home as enforced in the workplace (m,y emphasis)- which means not just working safely but an entire industry built around redundant actions (e.g. annual PAT testing of leads that are only ever moved for their annual PAT test) and the keeping of excruciatingly detailed maintenance records, locking out the supply when we change a socket, labelling damaged equipment, not modifying equipment(!) and what about the use of non-trade items? Not to mention more useful but still admin heavy risk assessments and competence records and…

No, the regulation of safety in the workplace is based around the principle of legislating out risk. Real safety in the workplace is built around creating a genuine safety culture, and it is the latter of these (i.e. working mindfully and being aware of the risks and hazards) that we need to cultivate in our workshops, not the tickbox culture. Dare I say that common sense is the most effective piece of protective kit in any workshop?

These opinions come from some seventeen years of being on health & safety committees and over twenty years of risk assessment etc. with a sprinkling of formal training in the subject too!

Neil

[John OlsenParticipant @johnolsen79199]

So what about the possibility of running the lathe with an earth leakage breaker (RCD) ? Or even an isolating transformer, although they are big, heavy and expensive these days. That is what I would do with anything where I thought there might be any reason to suspect the integrity of the internal insulation.

But really, changing the plug, or having it changed, to the right one for the country seems like the proper long term solution

John

[Ian HewsonParticipant @ianhewson99641]

Havn't heard from the op lately, wonder if he is still laid on the floor?

[john fletcher 1Participant @johnfletcher1]

If he is getting an electric shock, never mind about the rights and wrongs, get the motor earth fault located and "FIXED". Don't ague about whether Myford supplied the motor or who wired it up, life it to precious, certainly fit an adequate socket and plug. Some of those continental grazing earth plugs are just as adequate as those in our 13amp.How do I know, I have been present when both type are being tested. The old round pin10 /15amp is/was a much better arrangement.John

[Anthony KnightsParticipant @anthonyknights16741]

I cannot believe this has gone on for 5 pages. Many posts ago someone mentioned leakage via RFI filter on the mains input to the machine. At the risk of showing granny how to suck eggs I will say the following

The impedance of the capacitor in the filter between live and earth (typically 1 to 3.3nF) will be between approximately 1 and 3 megohms. This is enough to give a tingle in the absence of an earth but the current will be a fraction of a milliamp and not dangerous. In spite of this, the machine must be earthed in case there is a real fault. Why on earth the guy cannot fit an Israeli plug to match his local supply I just can't comprehend. I also cannot understand why the people who sold it (assuming they are in Israel) did not have the correct connector fitted in the first place.

[john kennedy 1Participant @johnkennedy1]

I notice Nitai hasn't posted since the 4th.

He either took everyones sterling advice and is too busy turning

Or he didn't

[korbyParticipant @korby]

When I said straight out of the box I did not mean it literally. Dad bought a Brook motor thro his firm at trade price and fitted it. As he was an electrical engineer he knew what he was doing. Twas wired up with 3 core cable to a 3 pin plug and socket so was earthed. What was happening was the static was flashing over to the belt guard which gave a little tingle.

In those days Myford standard equip included a part machined chuck backplate so you could fit and skim to suit your chuck .if you bought the chuck from them with a new mc they would fit it at the works at no extra cost.

Today that chuck which was a 4 inch Burnerd 3 jaw sc only has a run out of 2-3 thou, can't be bad.

Its a good idea to run an earth from the machine bed back to the main earth point this ensures no nasty shocks.

Another thing he left was a beechwood carpenters mallet , he got it second hand in 1920 at Brighton street market for 2 old pennies. Well its a bit warped and batttered but also still going strong.

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