It is desirable that the wire be close in composition to the metal being welded. Otherwise, there is a high risk that the seam will turn out to be short-lived and of poor quality. Otherwise it will completely fall apart.
Today, 56 grades of electrode wire are produced. They all have different chemical composition. They can be divided into three main groups.
The first group is carbon wire. It contains up to 0.12 carbon. This wire is used to weld low and medium carbon steel.
The second group is wire for low-alloy steel. It contains nickel, chromium, molybdenum, titanium, manganese and other chemical elements. Well, the third group includes high-alloy wire.
Special tables can help you choose the right type of wire. According to the contents symbols It is easy to calculate the appropriate chemical composition of the wire.
Electrode wire is available in diameters from 0.3 to 12 millimeters. Most often used with a diameter of three to six millimeters. The wire must always be clean.
Electrode coating
The electrode coating is a mixture of various components applied and fixed to the electrode rod.
The inventor of the coated electrode is the Swedish engineer Oskar Kjellberg. He came up with the idea of coating the wire with silicate powder.
In 1908, German Imperial Patent No. was issued to Kjellberg. 231733 "Electrode and order electrical soldering". The patent states that the purpose of the coating is to “protect the molten metal from oxygen and nitrogen in the air, ensure the proper physical and chemical condition of the seam, and enable welding in all spatial positions.”
Today, two types of electrode coatings are most often used: thin or stabilizing, and thick or high-quality. The stabilizing coating ionizes the arc gap, thereby facilitating the process arc welding.
It weakly protects the molten metal from the harmful effects of air. But it still gives a relatively acceptable quality of the weld, although inferior to the base metal. The simplest stabilizing coating is chalk diluted in liquid glass (sodium silicate).
A high-quality coating regulates metallurgical processes during welding and improves the properties of the deposited metal. Compound high-quality coating quite complicated. It contains slag-forming, gas-forming, deoxidizing, alloying and stabilizing components, steel powders.
Nowadays, the most common electrodes in our country are those with calcium fluoride or, with similar properties, rutile coating. When melting, such electrodes produce flux, which protects the weld from the harmful effects of the atmosphere.
In Western countries, cellulose-coated electrodes have also become widespread. The metal rod is wrapped in plain paper, which is soaked in liquid glass and then dried. Such electrodes emit a lot of gases that protect the metal and the weld pool.
Anyone who has ever dealt with welding has probably paid attention to the clamping of the electrode - one awkward movement, and the rod changes angle, or may even fall out. Of course, professional welders do not encounter such situations, but an amateur would like something more reliable - rigid fixation of the electrode will allow him to perform welding work efficiently and accurately.
What materials will you need?
- Bolt (35 mm) and stud (70 mm) with thread 12;
- Extended nut (25-30 mm);
- Two regular nuts;
- Coupling nut (wing);
- Plastic holder (side handle) for an angle grinder.
Preparatory work
First of all, mark the center of the elongated nut, and then clamp it in a vice. With help conventional drill drill out through hole. The diameter of the drill should be about 1/3 larger than the possible thickness of the electrode. 6-8 mm. Make sure that the drill is strictly perpendicular to the edge of the nut.
Then we clamp the bolt in a vice and use a grinder to cut off the head. We weld a wing nut in this place. The length of the free thread must be no less than the distance from the edge of the long nut to the center of the hole made.
We unscrew the handle from a non-working angle grinder, drill or other similar tool.
The inner bolt is easily knocked out.
We clamp it in a vice and drill a hole for our stud.
Now you can start assembling.
Assembly of an exclusive reliable electrode holder
We screw the stud and the wing bolt into the wide nut so that they do not reach the edge of the hole made.
Next, we insert the entire structure into the handle and visually mark the place to which the fixing nut is to be tightened.
Then we twist the double nut, and on the opposite side we install the nut to the desired depth. We wind the wire going to the welding machine and clamp it with another nut, using two open-end wrenches for this.
We place the pin with the wire inside the handle and finally fix it with a double nut from the outside. Insert the electrode into the hole and tighten the wing bolt with a little force. Now you can start welding.
What you shouldn't forget
Throughout all the work, tools such as a drill, grinder and welding machine. All of them require increased attention, since failure to comply with basic safety rules and neglect of personal protective equipment (work gloves, goggles, welding mask and long-sleeved clothing made of non-flammable materials) can cause injuries, sometimes quite serious.
Trial
Having carried out test welding, I can say with confidence that our homemade holder is a complete replacement for industrial analogues. It securely fixes the electrode, and in cases of sticking it is quite easy to detach it from the surface to be welded (in the factory handle it often jumps out of the clamp and remains welded to the workpiece).
The only drawback can be considered the fact that this handle is made of plastic, albeit durable. During prolonged use, heating occurs in any case, and the handle may become deformed. Otherwise, it turned out to be an excellent handle, the cost of which is three nuts and two bolts.
Many people ask whether it is possible to make an electrode for welding ferrous metals with your own hands at home?
The answer is no. You cannot make a normal welding electrode yourself. Because this is a fairly knowledge-intensive process, and the components included in the coating cannot always be purchased at the nearest store.
What does the great and terrible Internet offer us in this regard?
Numerous welding websites claim that making an electrode is not a problem. Without going into the details of such production, you will need a steel bar, chalk, crushed to a powdery state (fine fractions). Liquid glass (silicate glue) is applied to the rod, then the whole thing is sprinkled with chalk and rolled so that it evenly adheres to the surface of the rod. The result is a chalky layer of some thickness. The homemade product is sent to the oven, oven or dried with a hairdryer.
And can you cook with this?
From our point of view it is impossible. You can equally well weld with a nail, rebar or bare metal rod. No difference. The process of such welding is unstable, the seam can hardly be called such, and there will be practically no slag due to the absence of slag-forming elements in the composition of the coating.
If you are going to do it yourself, it is better to use the idea proposed a hundred years ago by two Americans. They came up with the idea of simply wrapping the bar in paper and gluing it on liquid glass. At least it's easier than messing around with chalk. And the idea is very simple. The paper burns and emits smoke, which protects against harmful influence oxygen. Also, such a coating somehow improved ignition and had a positive effect on the stability of the arc... And this, of course, is very doubtful. Since easy ignition electric arc and the maintenance of its combustion occurs due to the low ionization energy of elements such as sodium, potassium and calcium.
In other words, you don’t have to worry about the composition of the coating and the method of application. If you really want to cook, but have nothing to cook with, and the shops are all closed for the holidays, take any piece of iron of suitable diameter and length, clamp it into the electrode holder and cook - this process cannot be called welding, but it is quite possible to grab something this way in extreme conditions. At the very least, this is no worse than the options proposed above.
Main consumables In manual arc welding, welding electrodes are used. Every master must have them, otherwise there will simply be nothing to cook with.
This product probably cannot be called scarce - today the choice of these materials is huge, there are products for joining different metals. The cost of some types varies within reasonable limits due to high competition in the market.
You can make a welding electrode with your own hands for experimental purposes, or in extreme conditions. You need to understand that manufacturing will require various raw materials, which may not be available on the farm.
Consumables
To make homemade electrodes we will need:
- binder in the form of liquid glass;
- limestone or chalk;
- low carbon wire of suitable diameter;
- roller or brush.
“Liquid glass,” with its scary name, is a fairly common product and is sold in almost every hardware store.
Manufacturing process - step-by-step instructions
So, we have decided on the materials and can start making electrodes with our own hands.
1. First of all, we need to grind the chalk to a powder. This can be done using a heavy metal object, but it is better to use a blender. So the particles will have a uniform structure and have a fine fraction.
2. We take steel wire and cut it into rods. You can use the factory dimensions as a guide and make rods 250 mm long.
3. The next step is to coat the steel rods with liquid glass.
4. Carefully distribute the crushed chalk onto flat surface. Roll out a steel rod coated in liquid glass over this surface, evenly distributing chalk particles over the body of the steel workpiece.
5. We wait until the electrode dries, check that the liquid glass has crystallized and put it in the oven at 100 °C for half an hour.
The welding characteristics of such an electrode will be low, it will produce a lot of sparks, be difficult to burn and stick. But when selecting correct modes welding and necessary preparation welded surface, you can achieve good results. Share your techniques for making electrodes or other welding materials.
I had one friend, a girl with a fragile figure, a welder. In everyday life, no one would have suspected that she was proficient in such a non-female profession. And only the holes from the sparks on the work pants could serve as indisputable proof that this was so. And, believe me, none of her fellow welders could compare with her in the cleanliness and evenness of the laid welding seam. She shared with me one of her many professional secrets - how to make electrodes for welding with your own hands.
To begin with, an educational program about what electrodes are and what they are made of.
Electrodes are generally divided into two classes: consumable and non-consumable. We will talk about consumable electrodes, which are widely used in welding work at home.
Industrially manufactured electrodes are a rather complex product, the basis of which is low-carbon, alloyed or high-alloy wire, which is covered with a complex layer of additional substances. These additional substances are needed in order to form a special atmosphere around the hot electrode, preventing access to it by oxygen and nitrogen from the atmosphere. In addition, the additives contained in the layer alloy the steel and remove harmful impurities from it.
Electrode structure
A list of tasks in the production of a welding seam and the substances contained in the surface layer of the electrode, with the help of which these tasks are solved:
Slag-forming substances that protect metal from nitrogen and oxygen. They include manganese ore, kaolin, titanium concentrate, chalk, marble, feldspar, dolomite, and quartz sand.
Deoxidizers that remove oxygen from molten metal. Manganese, silicon, aluminum, and titanium in the form of ferroalloys are used.
Gas-forming components that create a gaseous environment during the combustion of the coating, protecting the molten metal from oxygen and nitrogen in the air. These are mainly dextrin and wood flour.
Alloying substances that give the weld metal special properties - strength, heat resistance, wear resistance, increased corrosion resistance. For this, chromium, manganese, titanium, molybdenum, nickel, vanadium and some other substances are used.
Stabilizing elements that promote ionization of the welding arc - sodium, potassium, calcium.
Binders that serve to bind the coating components to each other and the entire coating to the electrode rod. The main binder is potassium or sodium liquid glass (silicate glue).
However, it happens that it is necessary to urgently apply a stitch, but there are no electrodes and there is no opportunity to run to the store either. Then my friend’s advice on making electrodes from steel wire with your own hands will help you.
Manufacturing of electrodes.
For this purpose, take steel wire of the required diameter. Typically this value ranges from 1.6 to 6 mm. Cut the wire into the number of pieces you need, 35 centimeters long. Prepare in advance a coating for the electrodes, which consists of a mixture of crushed chalk and silicate glue. Coating technology also matters: simply dip the electrode vertically into the mixture and slowly pull it out, leaving the upper end of the future electrode dry (about 3.5 centimeters).
Dry the electrodes in a vertical position, hanging them from a rope using a regular clothespin. Dry the electrodes until hardened. Sometimes, for speed, you can dry the electrodes in an oven with the air on.
Your electrodes are ready!
Welding electrodes
