Il filo di saldatura MIG / MAG non scorre bene, si blocca, fa spruzzi: come posso risolvere?

You are soldering and the wire does not flow well. The wire welder, perhaps, does not work

If it is true that there may be defects in the tools, the first thing to check is whether there are any situations in use that could compromise the proper functioning of a Mig / Mag welding machine .

The six most common problems with wire welding

1. Ground connection

The ground cable is used to make the connection with the electrode and is usually connected to the negative pole . It is good to specify that there may also be other situations in which it can be connected to the positive pole.
However, this step serves to close the path of the electron charge in order to start the flux and proceed with the welding.
The ground cable may not be placed well at times. In this case the flow of electric current does not converge and it is not possible to weld .

What can you do?

Check these items:

  • that the connector is well connected
  • that the earth clamp , or clamp, is well connected with the copper cable inside
  • that the clamp is hooked on the welding table , or better still, directly on the piece where you are welding.


2. Wire torch

Focusing on the torch, one of the most encountered problems is the closure of the gas nozzle due to dirt and encrustations of welding pellets and solidified material.

This happens because the welding wire is turned towards the material to be welded which can spray back on the torch itself. Furthermore, consider that the wire does not come out very straight and due to the force of gravity by placing the torch at a 45 degree angle, the wire will tend to fall towards the lower edge.

If there is already encrusted material around the nozzle, the wire will make contact with the material itself, causing a short circuit and malfunction of the welder .

What can you do?

You can act in several ways:

  • check the welding parameters . You are most likely jumping with too high a current
  • keep the welding gun clean . There are specific objects, such as the nozzle cleaner that you can use by squeezing in the nozzle, turning, so that the metal needles inside clean the whole area.


3. Diameter of the wire guide tip

As you know, the diameter of the wire can be of different sizes and care must be taken to correctly compose the torch with all the components suitable for that specific diameter.

In fact, if you have a tip with a diameter of 1.2mm and you use it with a 0.8mm wire, it is clear that the wire passes because the hole is wider, but at the same time the wire cannot fit in contact with all the walls of the hole. This condition can almost certainly lead to a “hiccup” weld.

What can you do?

Be sure to use a wire guide tip with the hole diameter of the same diameter as the solder wire you are using. The diameter can be found in small, stamped on the tip of the yarn guide itself.


4. Sheath

In addition to the right liner tip, you also need to choose the right sheath . If you use a steel metal sheath with an aluminum wire, the aluminum wire will tend to get stuck inside, making it very difficult to weld.

The same is true if you were using a 0.6-0.9mm diameter sheath with 1.0mm wire. It will hardly be able to flow well inside.

What to do?

The sheaths are made of different materials , depending on the metal the wire is made of. Choose the one that suits you best.

A steel spiral sheath is used to slide a ferrous wire, then of carbon steel or stainless steel.
When using aluminum wire or other light alloys, such as magnesium and copper, it is better to change the sheath. You can choose a Teflon sheath , that is, a smoother material that makes the wire slide easily inside.

In addition, there are specific sheaths for each diameter . It is very easy to recognize them by color:

  • blue : for wire with a diameter of 0.6 to 0.9 mm
  • red : 1 to 1.2mm
  • yellow : 1.2 to 1.6mm.


5. Wire drive roller

The wire feed roller is arranged in such a way that the wire can run through it . It may seem nonsense, yet, very often there are situations in which, perhaps due to haste, the wire roller is put on the wrong side.

Another place to check when the thread comes out discontinuously is in the thread press roller; if it is pulled to the maximum it means that our wire feed motor is really making a lot of effort and at times it could even “spit out” the wire.

What to do?

Proceed like this:

  • loosen the press roller a little (for example, place the knob between 2 and 3)
  • if you are welding with different diameters and wires of different materials, to be more precise, click on the vacuum torch button and put your thumb and forefinger in front making the shape of a circle . Do this when you are not soldering and check with your fingertips for the wire to come out - if the wire is slightly struggling to slide between your fingertips, then that is the right friction.

6. Gas bottle

Especially if you are new to welding, you may have difficulty with welding gas.

Without going into too much detail, we can say that the welding gas must be chosen based on the material to be worked on .

Here is an example: to weld iron with wire welding, it is better to choose a mixture of argon and CO2. If you don't use gas with solid wire then the weld will come out all black, dirty, full of pores. In short, it won't even be a weld; you will not be able to attack the material.

Finally, even if it may seem obvious, check that the connections between the cylinder and the welding machine are correct and remember to turn on the gas .

In fact, among the thousands of things to do, it can happen that you have taken this simple step for granted.

And you, what problems do you encounter when you sell? And how do you solve them? Tell us your experience, to make known more and more solutions on the world of welding.

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