question about Home-built Welding machine

[Loganguy]

Has anyone seen, or heard of, a home-built welding machine.

Back in the 1960's I saw a home-built welding machine being used. It plugged in to 220 volt AC current. The guy that had it said he built it from plans that he got from a magazine. The most striking thing about it was that it several large slabs of carbon through which the electricity passed. After about 30 minutes of welding, the carbon slabs were red hot at the point were the electrical contacts were pressed into the carbon slabs.

Can anyone direct me to plans for such a welder, or any information about such a welder?

Thanks,

 

[TOOLMASTER]

IT would have a transformer, rectifiers, maybe a choke coil

hard to guess an exact configuration

 

[awander]

http://weldingweb.com/showthread.php?26395-Salt-water-resistor-for-a-load

 

[Andre]

Do rewound transformers make decent stick welders? I'd like to make one for the fun of it, if it's a good idea. Not too great at electronics so I just want to be sure first before I plug it in and the lights go out with a click of the breaker!

 

[ericc]

Yes, they work. But unless you like goofing with a messy microwave oven transformer, it is much easier to just buy an old junk stick welder. They do not have a very good adjustment. You will have to figure out something for that. Also, it is difficult or expensive to wind the secondary, and there is nothing in the microwave that can be salvaged for winding it. I made one, but a junk Craftsman 110v stick welder (underpowered) is much better, especially if you can get one for $20 at a yard sale. The transformer will get hot, and it will burn out if you don't weld with it (the primary does not have enough magnetizing inductance to idle like a welder does). Anyway, mine does work and I will use it this weekend.

 

[Ozwelder]

The transformer is the heart of any welding machine.Cheaper manufactured weld transformers skimp on construction and while they are welders within the meaning of the word they are not so good as a welder machine. Other transformers taken from microwaves and such may not be adequate for long term operation

Some of those who have been successful in good making welders built around transformers with a good number and quality of the insulated lamination's and choosing a suitable transformer is the bedrock foundation your welder will be built upon.

A good transformer should be capable of producing a good flux density which is vital for a decent welding arc.Another thing a good transformer unit should be able to do is to tolerate the heat created from welding.Dissipating lots of heat means energy loss which should be directed toward the welding arc.

Building a welder is no mean thing so the effort directed into it should not be wasted on something not proven to work. These terms above need to be studied and understanding of the the effects of the flux density on a welding arc needs to be gained well before the build begins.
There are quite a few examples of home builds I have seen on the net.They just need to be searched for by Google.

Oz

 

[Morgan RedHawk]

I found this site several years ago. It shows how to build a TIG welder using an AC Tombstone as a base. It is the most sophisticated of the home built welders I have seen.

It does not look terribly difficult if you have some soldering ability, and some basic electronics knowledge. There are schematics for all the parts, and some PDFs of the PCB board layout (making the PCB is not terribly difficult. If you have never studied on it, do a search for "how to build a circuit board" and it should turn up some good sources..here is one link I found: http://www.instructables.com/id/Making-A-Customized-Circuit-Board-Made-Easy/). Barring making the circuit board out of PCB, you could always use bread board.

At one point, I looked into finding all the transistors and chips, and other parts. They are commonly available from many suppliers. I don't have my list anymore, unfortunately. You should be able to figure out all the parts needed from the schematics, though.

I have not tried to build it, but have been thinking about it again lately. I think it would be a fun project.

Here is the link for the welder: http://www3.telus.net/public/a5a26316/TIG_Welder.html

 

[Rbeckett]

Generally it has been my experience that you are rarely capable of building a satisfactory welder on your own, even from plans and schematics from the big three. The time and expense added to the high failure rate and low duty cycles make them almost unusable from the start. A good stick power supply has OCV reduction, hot starts. and is capable of having fine control over the output amps at the turn of a knob or push on the pedal. While it it technically possible to build a device that will wled it will lack nearly all of the features which you need to make safe high quality welds that will stand up to testing. As a purely technical experiment it can be done, as an alternative to just buying a welder it is definitely cheaper and more convenient to order what you really need to do the job you have at hand. By the time you wind the reluctor and transformer and get it properly insulated you usually have a good bit of money invested and still have a loooooong way to go to even attempt to strike the first arc. With the current prices of welders it is almost a sin to waste the money and time attempting to do it otherwise. A licoln tombstone can be had from just about anywhere for 149 bucks and an AC/DC is just a few bucks more. Consider the job you have at hand and what you hope to accomplish and do the math on a new Mig, Tig or stick and you will find that even a decent entry level tig is with in the reach of most home machinists budgets anymore. And it comes in a box, ready for gas and rod and to basically go to work immediately. Just my .02. Not trying to dissuade you in any way but re-inventing the wheel is expensive time consuming and rarely satisfactory when you look at cost versus what you have built. Sorry.

Bob