This is a fine plate soldering iron for almost any metal (I believe that I could still work with aluminum). It does not require the use of many materials unless they are very fine rods. One is not electrical arc welding. What founds the metal is the graphite end that in short circuit is put to the shining target. What the graphite is warmed up by the current is more than nothing, not the metal, because first it has a much greater resistance and it dissipates the majority of the power. It is important that the graphite end is sharpened for two reasons:

1. - The more fine it is the meeting point de between the material and the end the more resistance to the current and the more temperature reaches.

2. - If the end is too heavy the heat easily transmits from the end the soldering iron and great part of him without reaching the necessary temperature dissipates. The soldering iron only works if it concentrates the majority of the power in the point to weld.

Down an example of the soldering iron can be seen

One is simply a sharpened graphite bar, removed from a battery, holds to a conductive support of current (copper tube) and to a prudential distance a wood handle. The handle must be far enough as so that as much heat does not arrive as to burn it. Some insulating material of the heat can be used.

In order to hold it trumpets it of graphite become two you cut more or less in the song of the tube of longitudinal form dividing it in 4 parts equals. Two of them are eliminated and is the tube with two eyelashes. Each with pliers is tightened to give round form him and that adapts to trumpets it and soon one to the other comes near. We take a nut from great step that enters under pressure and, without trumpets it, we turned the nut with force doing spiral in copper. Later we opened, we put trumpets it and we return to do the same and is perfectly subject. This system allows to change trumpets quickly, to fit its position, and provides a good electrical contact.

In order to put handle to him, the copper tube is fitted in a hollow in the wood handle. Soon a hole is perforated and puts a screw, thus are sufficiently fixed. It is necessary to consider that the copper tube has connected a cable and this it must happen through the wood handle.

The soladador works with a transformer or a resistance of shower or irons. It is connected in series.

This is a photo of two pieces being welded. At the moment only we made loose points of weld because he walked little of power but modifying the transformer, with more tension will go better.


  • Although material is not contributed, the electrode is worn away because agglomerate is done with graphite dust, that I know, and note that is undone with the heat. Even so it lasts sufficient considering that leaves free and is many batteries

  • The graphite of pencils does not work.

  • The more it releases is it trumpets it and the more it excels of the better copper tube works. Surely it is because the graphite leads except the heat and the same has been trumpeting for of insulator that retains the heat in the end. If the end is closely together of copper loses much heat uselessly.

  • Sand it uses a transformer of microwaves of 1000w modified in order to give very to little tension and much current (5 volts and more than 100 amperes). It seems that due to the resistance of graphite, with the 5 volts does not remove the maximum power to him. I must try with more tension. It is necessary to avoid that the tension is as high as to make electrical arc (some 30v). The arc with graphite destroys the metal, graphite and is very dangerous for the eyes. Heavy cable is due to use.

  • Dark lenses or helmet are due to use to weld because the arc can mistreat the eyes.


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