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Arc Welder

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George L.

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Hello everyone,

I would like to make a simple arc welder to weld aluminum and steel for a few "projects." Nothing fancy, just something to get the job done. I was unable to find a schematic of a power supply for an arc welder, only people that want to sell me instructions. Does anyone know of a website or have a schematic of a circuit I could use to power the welder, preferably I would like it to be powered from a 12V deep cycle car battery, so I don't mess up the wiring in my house using so much current.

I would really appreciate if someone could help me out.

Thanks,

George L.
 
Hi George,

I hate to be a party pooper, but I'd suggest just buying an arc welder. As for the wiring, You would probably have to run new wires, I thing 10 awg is capable of 30 amps? As long as you wire it properly you should be fine.
I picked up a used stick welder to play with a few years back for only $100.00
But thats just my opinion
 
You can usually buy a "New" Hobby type Stick welder for about $100.00 on sale. And they just runs on 110 Volts.
Specifically the one I got was from Sears, But in No way Am I advertizing them, or implying you get one from them!

Its not the Best, But the one I got works quite Good, using welding Rods up to 1/8 inch, and welding up to 1/4 inch plate steel.

Thats Probably Better than Anything that would work from a Car Battery.
 
Has anyone ever had good results using a DC stick welder to weld Aluminum?
I use a MIG with Argon gas.
In the end, it will be cheaper to buy your welder, as they are now available for less then $120 CDN.

Unless this is a project, just buy it. Plus you eliminate the possibility that the equipment is at fault, when you see that your weld is bad. You would only have to adjust and perfect your technique.

Aluminum is not the easiest thing to work with.

Good Luck.
 
Speaking of Aluminum, If you are going to buy a welder, First Try to find out if it uses Copper or Aluminum in the Windings.

Avoid any welders with Aluminum. They are less efficient and do not stand up over time.
 
George L. said:
Hello everyone,

I would like to make a simple arc welder to weld aluminum and steel for a few "projects." Nothing fancy, just something to get the job done. I was unable to find a schematic of a power supply for an arc welder, only people that want to sell me instructions. Does anyone know of a website or have a schematic of a circuit I could use to power the welder, preferably I would like it to be powered from a 12V deep cycle car battery, so I don't mess up the wiring in my house using so much current.

I would really appreciate if someone could help me out.

Thanks,

George L.

As others suggested, welding aluminium is not as simple as welding steel, you are MUCH better off to get suitable welding equipment for it. It would also pay to do a welding course, I can tell from your post that a good course would not go amiss.

As to welding from a battery supply, it IS possible for steel and has been done successfully. Deep cycle batteries are not a good idea as they are designed for lower currents over a longer time. Starter batteries are designed for high current over a short time, just as required for welding.

A single 12V battery has insufficient voltage to get the arc started, you need at least two or better 3 batteries connected in series with substantial copper straps for a 24V or 36V output.
If you search in google for '4WD emergency welding' you should find detailed instructions how to hook it all up - unfortunately the URL is not on the computer I'm using now.

Klaus
 
Thanks Klaus,

the website you told me is perfect. The welder is simple and easy to make, just one question...the website says:

"One would normally keep the work as far as possible from the batteries, and cover the batteries with a ground sheet or blanket. This reduces the possibility of sparks from the weld igniting the hydrogen gas produced by the batteries. "

Car batteries release hydrogen gas? Maybe a little inside the battery where the reaction is taking place, but I didn't think there was enogh to leak and possibly cause an explosion??? :shock:

Is what the website is saying true, in that case is it safe to use this contraption to weld?

Thanks,

George L.
 
When you are Drawing this kind of Current, The Batteries can produce a LOT of Hydrogen. And YES, It can cause an Explosion.

And about the only way to limit current when using these batteries is by properly Controlling the lenght of your Arc as you weld.

Heaven Help You, If you accidently get your Rod STUCK.
BATTERY MELT DOWN!

This is Not a Very Practical Solution for Welding. Maybe OK in an Emergency.
 
chemelec said:
When you are Drawing this kind of Current, The Batteries can produce a LOT of Hydrogen. And YES, It can cause an Explosion.

And about the only way to limit current when using these batteries is by properly Controlling the lenght of your Arc as you weld.

Heaven Help You, If you accidently get your Rod STUCK.
BATTERY MELT DOWN!

This is Not a Very Practical Solution for Welding. Maybe OK in an Emergency.

You are right - it IS for emergency welding. But its not quite an uncontrolled current supply as you make it out. Have a look at the site:

https://www.safari4x4.com.au/80scool/tech/batweld/batweld.html

And you see they use smallish gauge jumper leads or even fencing wire to connect the batteries, which would limit the short circuit current somewhat. Certainly limit it to the extend to be able disconnect the rod holder from the welding rod should one manage to get it 'stuck'. Before battery 'melt down' occurs anyway :wink:

Klaus
 
Hi George L,

I remember using a 'welding kit' made to run from a 12v car battery
in the early sixties.
It was a strange contraption, and i have never seen one since then,
it had a crudely made solenoid in the rod-holding handle,
which made the rod pull back about a sixteenth of an inch or so
when contact was made, this solenoid being in series with the rod
also stopped the current.
This contraption would sort of vibrate quite firmly in use, and by
varying the pressure gently on the rod quite an acceptable arc could
be made, I never did much with it, I only got it as something to
play around with, i did manage to 'stick' a few bits of metal with
it, but i soon lost interest.
It would only manage very thin welding rods, i think they used to be
called 'sixteens' or 'sixteen gauge'.

I think i still have it somewhere, it's the sort of thing i would
hang on to, if i come across it i will post some pictures.

As for electric Aluminium welding, unless you're prepared to spend
time and money you won't get far. There are two usual methods of Ally
welding ... 'TIG' and 'MIG'

TIG involves using the arc rather like a flame, producing the arc with
one hand, and adding the weld material rod with the other hand.
Takes a lot of practice and experience in differentiating between
many different grades and types of aluminium, which often look very
similar, but which not all co-here to each other very well. This also
affects the choice of rod material, which may or may not need to be
the same.

MIG to my mind is a lot easier, you use a reel of ally wire feed,
again the operator has to decide if the parts and the wire are
compatible. You can buy a kit to convert a normal MIG set-up to use
it for aluminium welding. It a bit of a hassle, but it works ok.

************************

Batteries do give off hydrogen, charging or discharging, and yes it
can go bang. The most usual source of ignition in my opinion is poor
or loose connections on the battery terminals. In many years of
battery charging and discharging and swapping on vehicles and jump
starting with car batteries, i have only twice ever seen a 'pop' of
a flame from a car battery. But i can imagine that if it occurred
in some awkward place, maybe where it could have built up then it
could be just as serious as any explosion, with acid thrown in for
fun.

Ever since i saw that 'pop' which was a yellow flame, i knew what it
was and i have made sure that i charge batteries in the open air,
adequately ventilated. And since then i have never looked directly
down into the cells when fiddling with the hydrometer, something i
did used to do before. Now i tend to turn off the charger when doing
anything much to the battery. It made me a bit careful.
Having said that, i think it is pretty rare.

Best of luck with your welding project, John :)
 
thanks for your help john,

I don't think I will be using the battery idea any more. I found out it is extremely hard to weld aluminum, even for experts. It will probably be impossible for me to weld aluminum with some makeshift "welder." The batteries would probably cost $75 all together at best! I figured I will try to buy some type of "high temp metal glue" that can bond to aluminum and hold on at very high temperature(If it even exists).

thanks,

George L.
 
George L. said:
.... that can bond to aluminum and hold on at very high temperature(If it even exists).
George L.

Have you considered rivets?

JimB
 
They Also Make "Aluminum SOLDER".

And You can Solder with just a Small Blowtorch.
 
Hi,

This site is worth a look,
**broken link removed**

Heres a bit of a review, ... :
**broken link removed**

I am so impressed by these claims that i am looking for a UK
retailer to buy this kit.
So far i have been unable to find it available in the UK.

If it works as well as is claimed, i feel sure it would be a
great help to me.

John :)
 
Has anyone even bothered to study why Aluminum is so hard to weld???

First things first, both joints must be clean.
Next, you either etch the surface chemically(best), or with sand paper, or mechanically.
You have very little time to join the pieces together as Aluminum will form a small coat of oxidization almost immediately.
Furthermore, this oxidization process is accelerated with the application of heat.
Mig welders work because they have enough power to blow the arc through this oxide, and at the same time, coating or flooding the aluminum with a non oxidizing gas such as Argon or with less success, C02.

I recently read that this entire process can be replicated by first cleaning, then applying a thin coat of motor oil to the parts, and then soldering with Aluminum solder???
I have my doughts, but hey, who knows, I've been wrong before.

Anyways, there is a reason why welding shops love customers who need to have Aluminum welding done. $$$$$$$$

Good Luck.
 
hjl4 said:
I recently read that this entire process can be replicated by first cleaning, then applying a thin coat of motor oil to the parts, and then soldering with Aluminum solder???

I don't know about motor oil?, that's adding contamination to the joint, but soldering aluminium is fairly easy - with the correct solder of course, and clean the surfaces well before soldering, just as with any other joint really.

There's a museum in Sheffield, obviously based on their old steel industry, and one of the exhibits is a welding example from a college. It consists of various dissimilar metals, aluminium, stainless steel, tungsten, etc. - all welded together, and then cut in half through the joints. It's an incredible example of really beautiful and skillful welding.
 
aluminum&steel

my father was a welder and he had 2 dirrerent machines for each type material.he was heli-arc welding mostly and explained to me that to weld aluminum the machine is set up to operate at higher frequency than the steel.don't quite understand what he meant to this day cuz I was about 12 or 13 when he splained it. but I weld now some 17 yrs later and yeah aluminum is hard to weld period. my pops used to weld 2 aluminum cans bottom to bottom and didn't burn 1 hole thru either one .. the man was good! rip dad
 
Guess again.... Using CO2 as a shielding gas for aluminum will result in a nice pile of white powder and nothing else. Argon or Helium are almost exlusively used for aluminum, sometimes the two are mixed. Mixtures of gases containing CO2 are used for steel alloys, and sometimes even oxygen is added for MIG welding. The small amount of oxide formed on the tip of the wire breaks the surface tension of the weld puddle. Hydrogen and/or nitrogen are also used in mixtures for other metals. To my knowledge, NO mixtures for aluminum welding call for CO2. CO2 aids penetration in steel welds - Argon and helium reduce spattering and produce different temperatures. 75% He and 25% Ar is a good all around mixture. Pure CO2 should only be used on Silicon bronze or (non stainless)steel!!

Ive never heard of, or seen anyone chemically etch aluminum before welding, and I cant see any advantage to this practice. Small amounts of surface oxidation are, like you said inevitable, but they do NOT hinder the possibility of a good weld. A visibly clean (NO OIL!) surface and a quick rub with a stainless steel brush is good enough. Any welder with a high frequency start will easily and quickly burn through this layer of oxide.

Also, many of the top welders (Miller Synchrowave300, Linde 300, Airco DipPac200) use aluminum in the power busses. Mine are 16, 30+, and 21 years old, respectively, and have never missed a beat. Aluminum in transformer windings??? I dont think so!
 
chemelec said:
When you are Drawing this kind of Current, The Batteries can produce a LOT of Hydrogen. And YES, It can cause an Explosion.

Wrong. Lead acid Batteries usually have bigger than necessary negative electrodes relative to the positive plates. This excess of lead sulfate and sponge lead reacts with any electrogenerated oxygen and hydrogen ions to form water. Hydrogen gas generation should only occur in large quantities in conditions of overCHARGING. Discharge doesnt generate any.

Explosions occur because the battery shorts out internally, arcs, and ignites gases that are INSIDE the battery. Sometimes it even happens when the batteries are NOT being abused! The chances of the stoichiometric ratio being good enough to facilitate an explosion or combustion once outside the battery are pretty slim, and can only be exacerbated by covering the battery with a blanket.
 
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