Nowadays technology plays one of the most important parts of our life. As every day goes by, we are introduced to more new technologies. Some of them are easy using while some are difficult. And when it comes to using these technologies, we make mistakes using them.
Today, we are going to talk about a technology named TIG welding and the mistakes people make usually using them.
- 1 TIG Welding Principal
- 2 Advantages and Disadvantages
- 3 10 Most Common Technical Mistakes
- 4 Tips to Avoid TIG Welding Mistakes
TIG Welding Principal
The softening temperature important to weld materials in the Gas Tungsten Arc Welding process is acquired by keeping up a curve between a tungsten combination terminal and the workpiece.
This welding temperature can approach 2500℃. An inert gas is used to protect the molten metal from atmospheric pollution. Herein, the inert gas is usually argon, helium, or a combined mixture of helium and argon.
Advantages and Disadvantages
The amount of control it allows is the greatest advantages of all. Using a foot or thumb control switch, the welder can control the heat and ampere. TIG welding is a very good process for projects where base metal requires detailed designs and curves.
The process works very well on thin pieces of metals as TIG welding uses a low amperage. The advantage of the combination of low amperage and remote control switch allows welders to shift working from thin or thick metal pieces quickly, which makes it a variable process.
The arc of the flame is separated from only a little area of space, from the base metal. So the process requires a high level of eye focus and precision.
TIG welding process requires high skills and patience as the process is usually time-consuming.
10 Most Common Technical Mistakes
As beginners, new welders are meant to make mistakes. No matter if they had completed their technical school or college welding program, doing it on the job will help them with the practical knowledge.
Many mistakes are okay and will help them learn. Making those mistakes once, you will not be making it again. Many errors can be fixed just with a torch and grinder, if only they fall into the “helping you learn” category.
While some technical mistakes are not as easy just to be fixed with a grinder and torch, they can lead you to severe results, such as equipment collapse, wreck materials, injuries or even losing a life.
Poor Gas Coverage Leads to Contamination
The contamination usually occurs when the shielding gas is turned off. There is either too little gas or too much gas covering or the gas is blown away. The contamination gas issues while:
- Not checking the gas cylinder label; using the gas cylinder without checking leads you sometimes using the wrong type of gas.
- Not setting the proper gas flow rate.
- Using a standard collet body instead of using a gas lens.
- All the fittings and hoses are not checked if they are leaked or not.
Choosing The Wrong Current
Many people usually make a popular mistake, mainly the beginners. They use the wrong flow while welding the metal. They do not remember which current to use AC or DC while using the type of metal and electrode.
Being a TIG welder, you need to know which type of current to be used. Using the alternating current (AC) is ideal. As welding with a direct current (DC) will be difficult on eliminating the aluminum oxide layer. This layer will mix with the filler material resulting in contamination.
The AC cycle blasts away the oxide. Yes, the positive electrode portion of the AC cycle does these while the negative electrode portion helps to melt the base metal.
Many new welders are also making a mistake using the wrong temperature setting.
The gritty appearance seen on the metal pellet is usually caused welding at a high temperature. Which cause the base metal to be weak.
Beginners make this mistake often; using the wrong type of filler metal 4043 instead of 5356 filler. The rod they use seems to defect. And they do not remove all grease, oil, and moisture from the surface which leads them to contamination.
Lack of Combination
One more mistake new welders make is welding the T-joint or fillet by;
- Improper fitting up and holding the torch far away from the joints.
- Feeding the filler rod improperly.
- Welding too quickly.
- Without reducing the arc length, losing the directional control and decreasing the force.
While welding craters or hollow is made which leads to cracking, it is usually caused by dropping the weld power instantly and removing the filler rod quickly. They do not adjust their technique which makes them make this mistake often.
Not Cleaning Your Materials
The first mistake that all new welders make is not cleaning their materials before welding. All the filler and base metals require cleaning, whether the contaminant is oxidized on aluminum, mill scale or dirt and grease covers the filler metals.
Sadly, this cleaning usually isn’t done. And if they do the cleaning, they always use the wrong brush.
The Poor Color on Stainless
The excessive discoloration on a stainless steel weld is caused by overheating and atmospheric contamination. This removes the corrosion resistance and mechanical properties which makes the metal unusable.
Sugaring on Stainless Steel
The sugaring usually occurs around the weld when uncovered to oxygen in the air. This happens while overheating the weld and not having sufficient gas coverage on the front and back.
Using Too Much Amperage on Aluminum
Setting the amperage too high creates a broader outline, a poorly characterized dot and can burn through.
Improper Arc Length
The frustration which is most familiar to beginners is to strike the arc. They either lift the arc too far from the surface or too close to the base metal hitting the metal too hard and sometimes not even knowing what they need to do to start the arc off.
Here’s a cool video about the Basics & Common Mistakes of TIG Welding
Tips to Avoid TIG Welding Mistakes
Human beings aren’t perfect; it’s obvious that we will make mistakes. This is just how we are, but this shouldn’t stop us from being cautious.
TIG welding takes years to master and even after years of practice, one can never say proudly that he will not make any mistakes in the future. Making errors are typical, but learning from your mistakes is all that matters.
Down below, I will list some common welding mistakes which you may have already come across or will encounter shortly. I will also discuss how to avoid them altogether.
Lacking Fusion on Root
Many factors may lead to this error, the common ones being; if the fit-up is improper, if you are holding the torch from a long distance towards the joint and feeling the filler rode improperly.
The use of transformer based machine increases the chance of the error as the arch usually wanders off between the joints sides. This happens because the arch always searches for the side which is the least resistant.
To avoid just the inconvenience, what you can do is reduce the arch length. What this will do is give you better control over the direction and will also make penetration easier. Another solution will be using an inverter based machine.
Lack of Cleanness
Cleaning should always be the priority to all of you. Many of us think that cleaning the filling metal or base is useless, but this is a misconception. A dirty base or filling metal will cause imperfections in work and will often lead to disastrous finishes.
Discoloration of Stainless Steel
This being a widespread error which is made by many of us. Once the error is made, there is nothing you can do to revert the mistake. This being the reason, you will have to be extra careful not to cause the error in the first place.
To avoid the error, what you will have to do is keep a specific thing in mind; heat. Overheating stainless steel causes the steel to discolor which reduces its corrosion resistance.
How can you control the heat? Heat can be controlled in a lot of ways; reducing amperage, increasing travel speed or by cutting the length of the arch, etc.
Oxidation of Stainless Steel
Stainless Steel has manufactured in such a way that it becomes resistant to oxidation despite being a metal. Our mistakes while welding can make the stainless steel lose its coating which prevents its oxidation.
Preventing mistakes which can lead to such issues is easy! Just be sure to back purge the weld with a shielding gas of argon or by reducing amperage.
These are mistakes which are made by the beginners in their welding careers. And with every mistake made, comes an opportunity to cover up. Mistakes are meant to be made, and it is just a matter of time to learn!
Learning from mistakes will help you solve many of the most common welding problems from the beginning.