Gasless Mig Welder

Gasless mig welder video, part 1.

Gasless mig welder video, part 2.

You can pick up a small gasless mig welder like this one in the picture below from you local hardware store or even online.

Places like eBay.com and Amazon.com are great places where you can buy a gasless mig welder online. Quite often you will be able to get a small mig welding machine significantly cheaper online as compared to buying a machine from a physical shop in town.

They are a bulky item and do weight quite a bit and are heavy. So keep an eye on the shipping and handling charges that will be added to the purchase price. It may well be better for you to pick up the machine locally from in town even if it does cost more, as the cost of shipping if buying online may outweigh the cost of buying it online. So there might not be any cost saving buy shopping online for one of these bulky items.

Gasless mig welder basics

Maybe you have never used a gasless mig welder before, maybe you're looking at buying one. These things are great. This particular machine is only a very small machine so don't go expecting any miracles from it, but they are ideal for all the small DIY type welding jobs at home.

This machine is only rated at 88amps, which is enough to do mig welding jobs for repairs to box trailers, making garden gates and welding car panels. This particular machine is a dual purpose mig welder. This means it can use both the self shielding gasless mig wire and also solid mig wire that requires shielding gas. At the back of the machine is a hose where you can connect up the welding gas bottle, and inside the unit it has plumbing to allow the use of a shielding gas for mig welding.

Because this machine can run solid mig wire with gas, it makes it an ideal choice for welding thin gauge car panels. This is better than using gasless mig wire, as that mig wire burns hotter and it will blow through car panels easily. Secondly solid mig wire generates a lot less spatter than gasless mig wire, so it makes clean up a lot less painful.

110v, 115v, 220v or 240volt mig welder?

Now this particular machine is a single phase 240 volt mig welder. This mig machine also requires a 15 amp plug. Because we are in Australia all of our single phase power outlets are 240, with the most common outlet being 10 amps. The plug here on this machine is 15 amps and has a larger earth pin. This means it will not physically fit in a 10 amp wall outlet, as the earth hole is not big enough to fit the larger 15 amp pin into it.

The solution is to have a dedicated 15 amp plug. This might mean that you need an electrician to come around and install a new outlet.

If you are from the USA or Europe I think you have a choice of single phase power. This is why you often see mig welding machines for sale that are 110 volt or 115 volt machines. Then you also have 220volt machines.

If you can't decide on which size machine to get, the simple question to ask yourself is this. If you plan on doing heavier welding, and more frequent welding get the 220volt machine over the smaller 110v/115v welder.

Mig welding gun

Now every mig welding machine has to have a mig welding gun.

A mig welding gun is what makes a mig a mig. This welding torch is made to suit this cheap mig welder. Industrial mig welders will have a dedicated fitting on the front of the machine where the torch can be disconnected. The most common connection today is what is called the EURO fitting.

The downside to the mig gun in this machine is that parts can be hard to get or they might not be available at all.

Any mig welding gun is basically the same in theory and operation, quality is another thing. When you squeeze the trigger the power flows and the wire is feed through the gun. When the wire touches the welding work piece it will arc and you begin to mig weld.

Mig welding consumables

A mig welding gun has a nozzle or a shroud which is only needed when you use a shielding gas.

When you welding with a gasless mig wire you DO NOT NEED the shroud to be on. The shroud is a consumable as too are the contact tip and the mig wire and even the tip holder / gas diffuser are welding consumables.

Earth clamp

Earth clamps are available in a few different types.

The one on this gasless mig welder is the most common type which is a spring clamp design. There are also other one you can get. You can get ones that are like G-clamps, you can get magnetic earth clamps or you can even bolt the earth cable and lug to the job.

It is important to make sure the contacts are clean on the copper contact points of the ground clamp. If they are dirty and corroded, get a file or some sand paper and clean them up. It is also a good idea to check that the braded copper ribbon and the nuts and bolts that hold the cable on the clamp are nice and tight. A bad earth can give bad welding performance.

Exhaust fan and vent

Make sure the exhaust vent and fan have a clear path to vent out the hot air that is generated from inside the mig welder.

 So keep about a half a foot clearance at the back of the machine from any walls or obstacles. Also you can see on this machine how it has been marked as 240volts / 50Hz.

Front panel controls

On the front panel there are all the welding controls that you need to set for your gasless mig welder.

There is the main ON/OFF switch, which on this machine will light up when it is on.

Above that there is a thermal overload light. This will come on when the machine gets too hot and needs to cool down. This happens when you reach the machines rated duty cycle.

There are two switches MAX / MIN and 1 / 2. This lets you have a total of four main voltage settings. So for the lowest power setting you would have it set to MIN and 1. For the maximum power it would be set to MAX and 2.

Finally there is the wire speed adjustment dial or knob. This controls the rate at how fast the wire comes out of the mig gun when you pull the trigger.

Inside the machine

 When we open up the side door of this machine we can see all the mechanical workings of a gasless mig welder.

There are three main areas or items here for me to point out.

There is the spool of mig wire which feeds into the drive roll feeding assembly and there is the lugs and terminals for changing the polarity of the welding machine for welding with solid or gasless mig wire.

Mig welding safety

Using a mig welder can be dangerous if you are being stupid. As in, don't be outside welding in a rain storm, duh.

Read all warning stickers and labels so that you are aware of the dangers. Make sure you use personal protective equipment such as thick clothes, boots, welding gloves and a welding helmet.

Gasless mig wire generates smoke. This smoke is bad for you so try not to breathe it in. Weld in a well ventilated space.

 How to put the mig wire onto the welder

The next step will be how to put the mig wire onto the mig welder. So for this you need to use a self shielding flux cored wire, otherwise know as a gasless mig wire.  This wire is marked as AWS E71T-GS. 

"Do not confuse this wire with another type of flux core wire that has a similar number, as that stuff does require a welding shielding gas."

Once you have your spool of mig wire open it up from the box and remove the plastic or foil wrapping.  Find where the end of the wire is and bend the it so that you can unwind half a turn of wire.  Be careful that the wire does not unwind all the way.  DO NOT left go of the wire.  Because it is under tension it will go, twang! and there will be mig wire everywhere.

Once you have the wire undone, take some pliers, side cutters or nippers and cut off the end of the wire so that that bent bit is removed.

Also check with you fingers if there are any burrs or sharp edges at the end of the wire.  If there is you will have to re cut the wire untill you get minimal sharp edges.  You can even lightly squeeze or tap the wire into shape if the burrs are bad.

 Now you need to straighten out a few inches of wire.  This will make it that little bit easier to poke the wire into the small hole of the liner.

Now put the spool of wire onto the machine hub or machine axle/shaft.  Make sure the wire will line up the right way.  So on this machine the drive rolls are at the bottom, therefore the wire need to be coming off the roll from the bottom. 

If the wire was put onto the welder with it coming off at the top, the wire would be bending sharply to go into the drive rolls.  A big no no.

Feed the wire through the small plastic "guide tube".  This is there to help aim the wire and align it onto the feed rolls.

Once the wire is toughing the drive rolls you can slide it in to the start of the mig liner.  Make sure it goes into the liner hole, not beside the liner into the moulded plastic that holds the liner inplace.

Also on this particular machine the drive rolls do not line up with the wire 100%.  So I have to pull the wire down and hold it in place. Then I use the screwdriver to hold the wire in the groove of the feed roller whilst I lower the top drive roll down. 

Before you can feed the wire fully through the liner you should remove the contact tip. 

This will make it easier for the wire to feed through the end of the mig welding gun where the gooseneck and gas diffuser are.

 Once that is done you can adjust the tension on the mig wire.

Here you need to adjust two separate areas.  The first part that you need to adjust is the actual tension on the drive rollers.  This is how tight the wire gets pinched or squeezed.  To do this you simply twist the nut clockwise or anticlockwise to get the desired tension.

Do not over tighten the tensioning mechanism because gasless mig wire is very soft and it will deform out of shape.  This deformation of the mig wire can lead to possible wire feeding issues, which will in turn lead to bad welds.

The second adjustment we need to make here is how much tension or friction is applied to the spool of mig wire.  When you are mig welding and you let go of the trigger the wire spool wants to keep turning.   If this tension is not set right and it's too loose, the wire will want to unspool.   It needs to be adjusted so that it is tight enough to stop the wire from unwinding, but at the same time it can't be done up too tight otherwise the drive rollers won't be able to pull the wire off the spool.

Now you can plug the machine in an turn it on.  Stand away from the the mig welder holding the gun out nice and straight without any kinks in the cable.

Press the trigger and the wire will slowly start to feed along the inside of the mig welding gun.  You can if you like increase the wire feed speed to make this happen faster. 

Put the contact tip back on.  Thread it over the wire and screw it up tight into the tip holder. 

Finally get your pliers and snip off any excess wire.  Leave about 10mm or 1/2" of welding wire sticking out of the end of the gun.

 Go here if you are looking at buying a gasless mig welder / flux cored welder.

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