warco lathes.

[Antony PowellParticipant @antonypowell28169]

Hi Dave

You seem to be focusing on my Mig when the plasma is probably 10 times the size, the mig is on a completely separate ring main and is around 40 feet from the lathe

And most importantly the mig & plasma were not used for around a month prior to the damage yet the lathe was on several occasions without issue.

therefore ruling out any damage being pre existing or caused by the other machines

Tony

Edited By Antony Powell on 26/04/2017 10:32:19

[SillyOldDufferModerator @sillyoldduffer]

Posted by Antony Powell on 26/04/2017 10:30:20:

Hi Dave

You seem to be focusing on my Mig when the plasma is probably 10 times the size, the mig is on a completely separate ring main and is around 40 feet from the lathe

And most importantly the mig & plasma were not used for around a month prior to the damage yet the lathe was on several occasions without issue.

therefore ruling out any damage being pre existing or caused by the other machines

Tony

Edited By Antony Powell on 26/04/2017 10:32:19

Yes, guilty as charged! I've done a little electric welding and can imagine ways in which it would be possible to do damage to something else by earthing it accidentally. I know virtually nothing about Plasma Cutters and would only be guessing, hence my silence.

I'm not sure about the logic of your 'ruling out any damage being pre existing or caused by the other machines' though. Although the damage was extensive, the photos appear to show that only the earth cabling was directly affected. It is likely that nearby parts were partially cooked too. For example, looking at the lathes mains cable, it's possible that the Line and Neutral were still working after the fry-up, but didn't last long in that state.

Whatever caused this I'm sure you'll be pleased to put it behind you.

Dave

[Steve Skelton 1Participant @steveskelton1]

David, so you are saying that if the fault lies elsewhere you are happy that Warco takes the hit for something which is probably is not their responsibility. We know where we stand with you then.

If an earth fault was present within the lathe then the earth loop impedence and resulting fault current at that point in the circuit is unlikely to have lead to the damage you see on an earth cable as it would have lead to the operation of the RCD.

Whilst supplier bashing is acceptable to a point, people who do not understand electrical basics should not come to snap decisions on a fault they do not understand.

[Antony PowellParticipant @antonypowell28169]

Hi Dave

Here's a simplified explanation of a plasma cutter…

A plasma cutter uses electrical current to melt metal similar to an arc welder or Mig it then uses compressed air to blow the metal away creating a cut rather than adding metal to join it together. the thicker the metal the higher the current required, in my case 50mm metal means a very big current draw (you should see the electricity bill)

Without opening up the cable fully from what i can see the live and neutral wires do appear to be ok

The comment about pre-existing and damage from other machines is simply explained

The lathe worked fine several times after the last use of any other machines so if it was damaged as you hypothesize why did it work fine and without issue so many times, why also was the damage contained within the lathe

 

 

 

To all

Out of interest and not knowing if its possible….

I currently also own a compact little box of capacitors capable of repeatedly jump starting a car or van requiring around 300 amps to do so

As the motor has two large capacitors for starting on it (as I understand it)  would there not be sufficient power stored within these to cause a similar amount of damage to a circuit ?

Tony

 

Edited By Antony Powell on 26/04/2017 12:34:05

Edited By Antony Powell on 26/04/2017 12:37:38

Edited By Antony Powell on 26/04/2017 12:47:44

[Michael GilliganParticipant @michaelgilligan61133]

Posted by David Standing 1 on 26/04/2017 10:06:58:

[…]

but involving trading standards, … now irrelevant due to the fact that Warco are giving a full refund.

.

David [and John Stevenson]

That is why I commented earlier, to Tony, that Warco's action might have been expedient.

[ I do try to choose my words carefully ]

MichaelG.​

[Frances IoMParticipant @francesiom58905]

an 80ft “garage” is I think prob best described as a 1000sq ft or so industrial light engineering premises – I wonder if the lathe was supported on steel bolts set into the floor thus providing an excellent earth connection which effectively replaced (or augmented) any neutral line derived from the 3 phase supply when other single phase machinery was used – the earth on the ring main should easily sink 32A (+ some additional safety capacity) but which current would probably fry the power lead to the lathe.

[David Standing 1Participant @davidstanding1]

Posted by Frances IoM on 26/04/2017 14:47:59:
I wonder if the lathe was supported on steel bolts set into the floor thus providing an excellent earth connection which effectively replaced (or augmented) any neutral line derived from the 3 phase supply

REALLY? .

[John Stevenson 1Participant @johnstevenson1]

Anyone else gets the impression of the blind leading the blind ?

[David Standing 1Participant @davidstanding1]

Posted by John Stevenson on 26/04/2017 15:18:45:
Anyone else gets the impression of the blind leading the blind ?

Receiving, loud and clear .

[Antony PowellParticipant @antonypowell28169]

an 80ft "garage" is I think prob best described as a 1000sq ft or so industrial light engineering premises

It Is actually my garage. at home….

[Frances IoMParticipant @francesiom58905]

David
“REALLY? surprise.”
ok I’m a retired MIET (+ C.Eng) tho my expertise was other than electrical power supply – but maybe you could explain where the neutral line is derived from and what can go wrong if one of the phases has some problem ? – the power to fry just the earth lead and not either the live or neutral supply line had to be external from the lathe

[Martin WParticipant @martinw]

What is clear from the above postings and pictures is that the earth line was subjected to an excessive current which caused the damage. What has not, as far as I have read, been considered is that the earth conductor of the ring main supplying the lathe will have been subjected to the same current and being enclosed could also have overheated damaging the ring main wiring as well; I also appreciate that the earth in the ring being significantly larger can stand much higher fault currents before overheating but I would suggest that this ring main is examined to see if damage has occurred.

From all of the above it is my opinion that a failure of component/s in the lathe did not cause the problem and it is down to an external problem.

Martin W

 

PS

With regard to the capacitors in the motor circuit they will not store sufficient energy to have caused this level of damage.

Edited By Martin W on 26/04/2017 16:29:53

[Antony PowellParticipant @antonypowell28169]

OK one last time

THERE IS NO DAMAGE OUTSIDE OF THE LATHE

THE WIRING IN THE GARAGE HAS BEEN INSPECTED AND PASSED AS A1 BY A FULLY QUALIFIED AND VERY EXPERIENCED ELECTRICIAN.

Tony

PS sorry about the shouting but after posting it several times it seems people either don't read the posts and actually take it in or are just ignoring it.

[SillyOldDufferModerator @sillyoldduffer]

So here's a circuit diagram that I think would recreate the damage visible in Tony's photos:

All you need to do is connect something capable of delivering a 100 Amps or so for a few seconds between an earth and the body of the lathe. That something could be a car battery, a welder, Tony's "compact little box of capacitors capable of repeatedly jump starting a car or van requiring around 300 amps", or similar.

Current flows into the body of the lathe. It does no damage to the lathe itself because the lathe is a gert lump of cast iron. However, when it reaches the common earth point inside the lathe, the current passes into thin copper wiring. This isn't designed to carry much more than 13Amps. The current runs down the mains cable, into the mains earth and completes the circuit back to the source.

The wiring inside the lathe (and perhaps the earth wire in the ring main) heat up like the filament of a lamp. I would expect it to cause exactly the sort of damage seen in Tony's photos. Live and Neutral are not involved in this scenario, other than that they are close to the earth wire in the mains cable. I think it possible that the lathe could survive the initial incident, and then work briefly despite the damage.

This is just supposition; to really know what happened an expert would have to look at the real thing. Still, if I ever need to deliberately damage a lathe's electrics, I think this is one way to do it.

I'm glad it's not my lathe!

Dave

[David Standing 1Participant @davidstanding1]

Posted by Antony Powell on 26/04/2017 17:37:32:

OK one last time

THERE IS NO DAMAGE OUTSIDE OF THE LATHE

THE WIRING IN THE GARAGE HAS BEEN INSPECTED AND PASSED AS A1 BY A FULLY QUALIFIED AND VERY EXPERIENCED ELECTRICIAN.

Tony

PS sorry about the shouting but after posting it several times it seems people either don't read the posts and actually take it in or are just ignoring it.

Tony

I bet you wish you had never posted anything at all now! .

[Frances IoMParticipant @francesiom58905]

Dave
yes that could explain the damage but suspect there would be an almighty bang + signs of a weld as the 100A hit the lathe bed

Tony – yes I understand there is no visible damage outside of the lathe + its powerlead – I’m assuming that the cct testing was done post lathe problem – if the current was fed down the earth wire within the ring I wouldn’t expect to see any significant change in resistance or insulation between L (or N) and E lines if the ring is tested in the normal way. I suspect any fault will be found elsewhere and that the lathe was an innocent casualty however untidy its internal wiring was – I do hope Warco report back on what they think the failure mode was.

[James AlfordParticipant @jamesalford67616]

Personally, I blame the pixies who come out at night. They have clearly become bored simply hiding tools.

James.

[David Standing 1Participant @davidstanding1]

Tony can't reply right now, he's on the phone to the Samaritans .

[fivethou hammerParticipant @fivethouhammer12006]

Can they fix lathes then…? 'Come and join us'……..

Poor Anthony has put a quite legitimate post on here and has taken a lot of bashing for it. He is not an experienced model engineer neither is he competent in the black art of electrickery. I fully understand that he would be screaming blue murder about his deep fried lathe having spent a substantial sum on it in the first place. Whatever the rights or wrongs of his use of the machine, or Warco's apparent intransigence in dealing with this matter, I feel for the chap.

Warco in selling modelling machinery to the amateur tyro will have plenty of experience in dealing with, shall we say the newby latheist, and would be quite right to have trading conditions that they will wish to adhere to. The compromise here has been made by the supplier who has blindly agreed to refund the cost of the machine without having inspected it. Good for Warco in the final analysis. I can see both sides to this story and can also see that a forensic examination of the lathe by the supplier would be cost prohibitive.

I couldn't help but also notice that in the early days of this thread, a good proportion of the Warco lathe owners reported machine malfunctions or what they call minor niggles. I wouldn't expect this at all and if the proud owner is able to fix these minor problems, it should be the case that he shouldn't have to.

No-one is a winner in this matter, but it might be a lesson that those who buy cheap, buy twice. I am by no means a rich man and can see the attraction of buying a machine that on the face of it does exactly the same job as an expensive one at half the price. I wish Anthony all the best for his future in this hobby and hope that whatever machine he settles on, he will get satisfaction from it. When I see something like this, I am very happy that I didn't buy this lathe.

Gary

[David Standing 1Participant @davidstanding1]

Posted by fivethou hammer on 26/04/2017 19:59:56:

Can they fix lathes then…? 'Come and join us'……..

Poor Anthony has put a quite legitimate post on here and has taken a lot of bashing for it. He is not an experienced model engineer neither is he competent in the black art of electrickery. I fully understand that he would be screaming blue murder about his deep fried lathe having spent a substantial sum on it in the first place. Whatever the rights or wrongs of his use of the machine, or Warco's apparent intransigence in dealing with this matter, I feel for the chap.

Warco in selling modelling machinery to the amateur tyro will have plenty of experience in dealing with, shall we say the newby latheist, and would be quite right to have trading conditions that they will wish to adhere to. The compromise here has been made by the supplier who has blindly agreed to refund the cost of the machine without having inspected it. Good for Warco in the final analysis. I can see both sides to this story and can also see that a forensic examination of the lathe by the supplier would be cost prohibitive.

I couldn't help but also notice that in the early days of this thread, a good proportion of the Warco lathe owners reported machine malfunctions or what they call minor niggles. I wouldn't expect this at all and if the proud owner is able to fix these minor problems, it should be the case that he shouldn't have to.

No-one is a winner in this matter, but it might be a lesson that those who buy cheap, buy twice. I am by no means a rich man and can see the attraction of buying a machine that on the face of it does exactly the same job as an expensive one at half the price. I wish Anthony all the best for his future in this hobby and hope that whatever machine he settles on, he will get satisfaction from it. When I see something like this, I am very happy that I didn't buy this lathe.

Gary

Well done Gary, a sensible post.

They have been a bit lacking in about the last three pages! .

[David Standing 1Participant @davidstanding1]

By the way, have we heard again from Gareth, who posted the original post?! .

[Michael GilliganParticipant @michaelgilligan61133]

Posted by David Standing 1 on 26/04/2017 20:07:19:

By the way, have we heard again from Gareth, who posted the original post?! .

.

We heard that he had seen the light, and bought a Denford Viceroy:

**LINK**

http://www.model-engineer.co.uk/forums/memberpostings.asp?c=144897

MichaelG.

[David Standing 1Participant @davidstanding1]

Posted by Michael Gilligan on 26/04/2017 20:22:19:

Posted by David Standing 1 on 26/04/2017 20:07:19:

By the way, have we heard again from Gareth, who posted the original post?! .

.

We heard that he had seen the light, and bought a Denford Viceroy:

**LINK**

http://www.model-engineer.co.uk/forums/memberpostings.asp?c=144897

MichaelG.

Hurrah!

Then this thread has at least achieved its original objective!

[Ian Skeldon 2Participant @ianskeldon2]

Wow the power cables have had a fair bit of current through em the by the look of it, not a clue what might have caused it but I think Warco have been very good in taking the lathe back and offering a full refund.

There are a few questions running through my mind (if off topic mods please let me know).

As far as I can tell from climbing over the lathes stocked by Warco and Chester, they are identical in most ways, having slight cosmetic differences to seperate the two brands.

So what other choices are available for those wanting a small/medium, new lathe? and are there any British made ones still in production?

Thanks,

Ian

[Michael BriggsParticipant @michaelbriggs82422]

Patience is a virtue, does anyone know where I can get a top up ?

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