# Forum Home Renovation Metalwork & Welding  "Weld" chain link with electricity?

## PlatypusGardens

I came across a discussion about this on the net somewhere but can't seem to find it now.
They were talking about fusing chain together by passing (probably ridiculously high) current through it.  
Anyone heard of this?  
I'd imagine it would have to get red hot for it to work?    :Confused:

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## CraigandKate

Yep that's basically how it works, same for all the spot welds that hold your car together! No filler rod, just current (to produce heat) and force/pressure to press the molten metal together! 
Check out 3:15 on this video:  https://www.youtube.com/watch?v=a9O_kGbEsW8

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## PlatypusGardens

Ah yes but I was more talking about doing this    
Without having to do this

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## PlatypusGardens

Would it be possible to do that at home with, say, a big old arc welder.........?

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## CraigandKate

Hmm sorry miss understood! 
Might be possible, you are going a bit beyond the recommended capabilities of a arc welder though! You seem like the kind of guy that is happy to give anything a go though  :Wink:  
You could try putting 4 links under a bit of tension (that is important), earth clamp one end and use a bit of steel instead of an electrode? Might do it!  
**dislaimer this may kill/maim or cure arthritis I really have no idea  :Smilie:

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## CraigandKate

Alternatively how many car batteries and sets of jumper leads do you have? About 10 should do it nicely

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## Uncle Bob

It would take *alot* of current to weld all the links at the same time.
Maybe be an induction welder could do it link at a time, but still, I reckon it would need a lot of current.

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## PlatypusGardens

Yeh thought as much....

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## David.Elliott

So watch tonight's news for the Breaking Story about the massive, unexplained blackout, complete with mushroom cloud and timber power poles discovered as small mounds of smoking ash, CURRENTLY (!) affecting Mackay

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## PlatypusGardens

I see what you did there

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## David.Elliott

I did use CAPS though...

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## METRIX

> Yep that's basically how it works, same for all the spot welds that hold your car together! No filler rod, just current (to produce heat) and force/pressure to press the molten metal together! 
> Check out 3:15 on this video:  https://www.youtube.com/watch?v=a9O_kGbEsW8

  NOOOOOOOOOOOOOOO, Now I have to watch 40 other How's it's made episodes, once you watch one you can't stop, AHHHHHHHHHHHHHHHHHHHHH

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## Marc

You call that a chain?
This is a chain  https://www.youtube.com/watch?v=k_LA_R4ifYk

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## METRIX

That's not a chain, this is a chain, each link weigh over 226kg ????

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## PlatypusGardens

> NOOOOOOOOOOOOOOO, Now I have to watch 40 other How's it's made episodes, once you watch one you can't stop, AHHHHHHHHHHHHHHHHHHHHH

    :Rofl:

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## PlatypusGardens

> You call that a chain?
> This is a chain

   

> That's not a chain, this is a chain

  Girls, girls, you're both pretty.   :Roll Eyes (Sarcastic):   
Can we carry on discussing how ludicrous it would be to attempt fusing chain at home in my shed now, please?      :Wink 1:

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## phild01

Hoist the chain over some high tension wires and and hang on tight to earth it

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## Marc

I don't think it is possible to zap a chain and make it stiff just like that. if you wanted to weld two links, you probably could with a large spot welder, but a meter or chain?   
May be if you swing it on high voltage cables ... noooo.
Best way of course is with a tig welder, you can hide the weld much better. 
PS
you could probably modify a spot welder and make the clamps in such way that one fits inside one link and the other at 90 degree to fit inside the other link. Zap, and then go to the next and so one.

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## phild01

> May be if you swing it on high voltage cables ... noooo.

  Marc, gotta stop channelling me

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## PlatypusGardens

> Hoist the chain over some high tension wires and and hang on tight to earth it

  
Hmmm does it not have to be DC voltage?   
*Googles locations of substations in the area*     :Zap:

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## Marc

Still thinking about how this could be made. 
I would experiment with a simple arc welder.
One copper bar into one link, the earth another copper bar into the other link. Press together and step on a pedal switch and let go .... mm just an idea.

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## ringtail

> That's not a chain, this is a chain, each link weigh over 226kg ????

  Bloody nora !

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## oldtrack123

HI 
The Machine used to make chains is referred to as a BUTT welding Machine[Two types upset butt welding & FLASH butt welding]
Each link is held in a clamp which is supplied with low4>8V voltage, very high current  AC.by means of a transformer
The Half  links are moved together until they make contact 
Then depending on the type of weld the links make contact then drawn slightly apart so arcing continues between the link faces 
When the faces are hot, enough the half links are rammed together
Actually it is an ELECTRIC forging process
Smaller dia links usually are lightly butted until they reach forging heat then rammed up
Small portable 240V manual Machine that did up to about 4mm round  were common in wire works throughout Aus in the 40>60s
The largest at that time could handle 100MM dia links  using the flash butt method & hydraulics for motion 
M/cs MADE IN AUS!!by EMF electric Co later CIG !
PeterQ  
 Chains/ Links  with bar up 100MM  use to be made in Qld something around a 450KVA transformer from memory
Company was Falkiner Chains!

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## oldtrack123

HI Mark 
You need HIGH current, 10000'S of Amps & low voltage 
PLUS pressure .
Those BIG links would be done with something like a 1000KVA Flash butt m/c but voltage would be unlikely to be much more than 15V
PeterQ

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## PlatypusGardens

> You need HIGH current, 10000'S of Amps & low voltage

  even for smaller stuff?

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## PlatypusGardens

> Still thinking about how this could be made. 
> I would experiment with a simple arc welder.
> One copper bar into one link, the earth another copper bar into the other link. Press together and step on a pedal switch and let go .... mm just an idea.

  I like this idea and also maybe the possibility of a home made spot welder. 
hmmmm

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## PlatypusGardens

I must see if I can get that big old "farm" arc welder off my mate.
He said I can have it as he got given it and will never use it......

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## PlatypusGardens

> That's not a chain, this is a chain, each link weigh over 226kg ????

  
Ah, anchor chain for a Maersk ship, makes sense.
Hey if you like docos, check out the one where they build the (at the time) biggest container ship Emma Maersk. 
The prop alone weighs over 100 tonnes    :Shock:

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## PlatypusGardens

Mmmmmhmmmmm   How to Make a Spot Welder for Cheap! « Hacks, Mods & Circuitry  
interesting interesting.  How to Turn a Microwave Oven Transformer into a High Amperage Metal Melter! &#171; Mad Science   https://m.youtube.com/watch?v=GCrqLlz8Ee0

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## Marc

Yes the microwave transformer may be ok for thin metal not for chain. If you can get an arc welder that gives 300 amp or more you are on a winner. 
Do you have 3 phase? 
I thought that if you want to just make a straight line of chain, you can give the pressure to the weld with a car jack hydraulic or otherwise. Anchor one end and place the jack on the other end and wind it up as much as possible. The chain will be under tension and the links under pressure. You then zap them and see if the welder has enough oomph.  
The observations further up about the butt welding process are spot on, but you don't need to melt or forge weld the chain to make it stiff. Only enough weld to keep it straight. Experimentation is the way. It may well be that it is so much mucking around that you will be quicker with a Mig or a Tig.
The advantage as I see it would be more to do with aesthetics since there will be no visible weld... if it works that is.

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## phild01

> I thought that if you want to just make a straight line of chain, you can give the pressure to the weld with a car jack hydraulic or otherwise. Anchor one end and place the jack on the other end and wind it up as much as possible. The chain will be under tension and the links under pressure. You then zap them and see if the welder has enough oomph.

   But how does that create an arc at the link.

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## Marc

well ... it is only a suggestion to experiment. If there is enough amps to melt the surface of the two links, and if the links are smaller than the chain Metrix posted ... that may just be enough to keep it stuck together. It will not be a proper weld.

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## oldtrack123

> even for smaller stuff?

  
Hi
The current required depends on the round dia & if it is a double weld of two U pieces or a single closing  weld in a C link
 Machines for say a single Upset BUTT  closing weld in a small "C"link  dia of  4mm  are  around 4kVA @ 4V 1000A
 Arcing with high voltage low amps dos not work. 
With small diai links, say 3<4mm, the welding faces  need to be in light contact so the the contact resistance helps generate the heat over the whole face.when the metal becomes plastic the pressure pushes the faces a together & leaves a small even ridge around the weld 
Very large Dia links & bars & Rail lines cannot be just upset BUTT welded as the current required would be enormous
  They are always flash butt welded

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## oldtrack123

Flash butt welding use slightly higher voltages
The faces are pushed together & drawn slightly apart without loosing the arc until the weld faces have a layer of liquid metal ,they are then rammed together & held clamped under pressure until the liquid metal has solidified
THe clamps need to fit the metal dia  & it is important the good contact is made as close as possible to the weld area other wise the heat will travel back & that area will crumple under the upset pressure the current that shunts around the C leg also has to be allowed for.

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## PlatypusGardens

Oldtrack, *with all due respec*t, you talk a lot and seem to know what you're talking about, but I'm not getting much specific information from your posts.  
so
Tell me this  
Can I somehow fuse or spot weld chain links with, say, 5-6mm dia links together in my shed with a makeshift device made from an old arc welder or transformer? 
As in, making a length of chain "stiff" (see post #3 in this thread) not MAKING chain from scratch.   :Unsure:   
I'm prepared to spend days/weeks mucking around with this.
You all know that.   :Wink:

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## oldtrack123

> Can I somehow fuse or spot weld chain links with, say, 5-6mm dia links together in my shed with a makeshift device made from an old arc welder or transformer?
> As in, making a length of chain "stiff" (see post #3 in this thread) not MAKING chain from scratch.
> I'm prepared to spend days/weeks mucking around with this.
> You all know that.

  HI
 Well ,l I guess it is a question of how strong you want the finished product to be 
 If you want full strength for   both legs & the chain is under any deformation stress, an unfused area  or flaw in the weld area could lead to failure .
Any clamp has to clamp sufficient area of the link surface so that hot spots do not develop weakening those areas Or they may also deform under pressure  the upset pressure 
The same with the back of the Link if doing a closing weld.
It too will shunt current from the actual weld 
I hope you are prepared to scrap a lot of failed welds or links 
If you just want it closed with little strength, you could simple put V the joint & Arc weld the gap

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## oldtrack123

An arc welding transformer will not give enough Amps to  upset butt or flash butt weld anything like 6mm Dia steel .
So long since I was involved, near 30years, that I cannot recall the actual currents req.,   but there is a formula based on bar dia
 I serviced the machines used for chains from 3mm up 100MM round
also metal window frames,  railway lines etc

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## Moondog55

Hmmm Thought experiment
No pressure so you put lots of amps through the links
Links need to be in great tension to be held straight and stiff
Current makes steel hot, hot steel softens and looses integrity
You see where I'm going with this? The only solution I can see is some very sophisticated electronic timing circuitry to dump thousands of litres of liquid Nitrogen on the hot chain just when it hits the melting point but before it collapses in a puddle of slag on the floor

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## Cecile

> *alot*

  Sorry, I'm being a brat.  Every time I see this word, I think of the following:  Hyperbole and a Half: The Alot is Better Than You at Everything

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## phild01

> Sorry, I'm being a brat.  Every time I see this word, I think of the following:  Hyperbole and a Half: The Alot is Better Than You at Everything

  And annoying when a 'definite article' is skipped, as a lot of Poms do.
Also use of 'your' instead of 'you're' and 'their' instead of 'they're'!

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## oldtrack123

Hi No real problem if the equipment performs the necessary functions 
The simplest version for light Section UPSET butt welds , requires a manual lever that controls the right pressure to get high heat into the contact faces then when hot enough is pushed home hard against a preset  stop that eliminates unnecessary bulging near the weld area
Even a little heavier section flash butt welds can be done  manually 
But the bigger sections  flash butts do require  hydraulically operated motion piston,  often with a back & forth motion  before the final ramming home
They do involve electronic timers
Only the weld area should get hot to the soft stage 
ANY local hot spots away from the weld area are not tolerated
 That is where the current , often water cooled ,holding clamps are so important.
They have to introduce the current as close as possible to the weld area, with no local hot spots forming away from the weld
And also hold the link firm , so  no slippage under the final ramming home
Manual clamps on small machine[often lever action]  
pneumatic or hydraulic  cylinders  on larger mcs.

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## oldtrack123

> Hmmm Thought experiment
> No pressure so you put lots of amps through the links
> Links need to be in great tension to be held straight and stiff
> Current makes steel hot, hot steel softens and looses integrity
> You see where I'm going with this? The only solution I can see is some very sophisticated electronic timing circuitry to dump thousands of litres of liquid Nitrogen on the hot chain just when it hits the melting point but before it collapses in a puddle of slag on the floor

  HI 
I am sure if you do a little googling you will find more on how it all works
but it is all tied up with the remainder of the link not even getting red hot!! & the system[RESISTANCE WELDING] has been in use for Donkeys years 
Machines were even being made in Aus in the 30s by the EMF electric co[ laterCIG]
 The major supplier to Aus industry way up into the80s 
ps I started servicing & fault finding welding problems with ALL sorts of welding Mcs round 1948

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## Marc

Alot of time your reading what their writing and your scratching your head tinking whatsamatterwithyou?   :Smilie:  
PS
It seems PG that it is not as simple as we thought

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## Moondog55

G'Day oldtrack
I was commenting on the OP
 If you reread the original question You'll find my tongue in cheek answer appropriate; I do know how chain is made, that's not what PG was asking
Why do we not have a "Tongue in cheek" emoticon?

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## METRIX



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## Uncle Bob

:Tongue:

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## phild01

Those one's are poking the tongue out whereas one is needed showing keeping a straight face, biting your tongue or holding the tongue in the cheek.  Sort of like  :Innocent:  :Whistling1:

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## PlatypusGardens

Meh. 
Guess I'll just make a metal melter then

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