With all the different types of welding electrodes in the market, it can be difficult to know whether you are making the right decision or not while choosing one for your stick welding project. Especially during the pandemic when you cannot go to a hardware store to ask an expert, the information on the internet can be a bit overwhelming. It is perfectly normal to be confused about the subject! Especially when you are new to the field. And it is very important to know that you are making the right decision when you are on a budget and you have to choose between multiple options.
To answer your question directly, they are both great all-around rods to be used. 6011 is a fast-freeze rod with great penetration and violent arc, while 7018 has more liquid puddle and soft arc. They both can be used in all positions and be run on AC as well as DCEP, however, 7018 is not a good rod for welding vertical down because of the amount of slag it produces.
USES OF BOTH THE ELECTRODES
The 7018 rod is engineered to weld high-tensile carbon-steel materials in all positions (but you do not want to run it downhill because it is too fluid). This electrode is commonly used in structural welding like in the construction of high-rise buildings and bridges. Due to the crack-resistant properties of the weld and the aesthetically pleasing look, this electrode is heavily preferred for pipe welding as well as heavy-duty equipment welding and general manufacturing purposes. It is advised to use the 7018 on hard to weld metals because of the low-hydrogen flux coating which helps in making the process easier. Overall, 7018 is pretty much an all-around rod if run on AC.
The 6011 is one of the most common welding electrodes out there because of a couple of factors, one of them being the versatility of the rod. It is a great all-around rod that you can weld a world, similar to 7018. The 6011 is also a fast-freeze rod which is an added advantage for overhead and vertical welds and also, 6011 can strike an arc very easily while hardly leaving any slag, making it ideal for tacking.
Both 6011 and 7018 electrodes should be dragged on the surface while welding but with 6011 you also have the option of weaving the arc a bit (whip it), but I have to say, 6011’s is much more manipulative. You do not want to manipulate 7018 because of the amount of slag it produces.
POLARITY DIFFERENCE BETWEEN 6011 AND 7018
Trust me, you don’t want to use the wrong current with an electrode. Some electrodes only work with either a DC- or a DC+ or multiple polarities and it is very important to check this before you start welding.
The numbering system which I keep referring to gives you a lot more information than you might have thought. The last two numbers of an electrode convey the flux coating of the electrode and also the polarity with which it can be used.
For the 6011 electrodes, they can be used with, DCEP and AC. Similarly, the 7018 rods are coated with a low-hydrogen flux mixed with potassium and iron powder compounds, so this electrode works best with reverse polarity as well – DCEP and AC. So, keep this in mind!
TENSILE STREGTH OF THE WELDS
There is a lot of information out there about the strength of the welds but in general, the first two numbers of each electrode represent the tensile strength of the final weld. So, for the 6011, the first number ‘60’ means that the final weld will have a tensile strength of 60,000 psi while the 7018 electrodes will deliver a tensile strength of 70,000 psi.
As a beginner or a hobby welder, I have to remind you that the actual strength a weld can carry depends on the quality of the bead itself. The numbers mentioned above apply only if your welds are perfect- Great penetration, bead profile, no undercut, and impurities.
THE PENETRATION DIFFERENCE BETWEEN 6011 AND 7018
The 6011 electrodes are preferred for welds that require a higher degree of penetration while 7018 only offers a medium penetration at best. Multiple factors affect the penetration, for instance, the current type being one of them as well as the flux composition of the rod.
The main reason 7018 does not penetrate as well because of the arc characteristics and the flux composition, which concentrates more heat to the puddle. On the other hand, 6011 has hardly any slag, which helps to concentrate more heat to the base metal, thus penetrating deeper.
THE POSITIONAL DIFFERENCE OF BOTH THE ELECTRODES
When you are choosing a welding rod, the position the rod can be used is a very important area to consider. Some electrodes out there cannot be used on a vertical surface or for overhead work. One way to tell the positional nature of an electrode is through the numbers assigned to it. The third digit of an electrode denotes the welding position of that rod.
If you notice the third number of both the electrodes, they are the same, that is, ‘1’. When the third number of an electrode is 1 it usually indicates that it can be used in any position. Both the 6011 and the 7018 can be used for vertical, horizontal, overhead, and uphill welds. 6011 can also be used for welding downhill but as I mentioned earlier, the 7018 is just too fluid for that.
KEY DIFFERENCES BETWEEN 6011 and 7018
- One of the major differences between the two electrodes is the fact that 7018 only provides medium penetration while the 6011 offers deep penetration.
- When you will be using the 6011, don’t expect the results to be pretty, it does the job, but it does not offer pretty beads to look at as opposed to the 7018
- Another major difference is the tensile strength which both of these electrodes offer. While the 7018 electrode offers a 70,000-psi minimum strength, the 6011 only offers a 60,000 psi. This plays an important role for heavy duty construction welds like skyscrapers.
One of the points of difference between the two electrodes is the way they should be stored. While the 6011 does not have any specific ways of storing them, other than the basic etiquettes, the 7018 on the other hand is pretty difficult to work with in terms of storage. It is important to store the 7018s in a moisture-free environment because it being a low-hydrogen rod. They should ideally be stored at 250 degrees F, for this, a lot of welders use a rod oven. If the electrodes have been out for less than 4 hours, they can be reheated at 700-800 Degree F.
|Tensile Strength||70000 PSI||60000 PSI|
|Position||All Positions except vertical downhill||All Positions|
|Polarity||DCEP and AC||DCEP,DCEN, AC|
|Arc Characteristics||Soft arc||Violent|
|Flux composition||Low hydrogen electrode||cellulose potassium (Fast Freeze)|
|Slag Type||Fluid, thick, does peel||Thin, flaky, does not peel|
|Motion||Drag Rod||Slight drag / Can whip (stich)|
FREQUENTLY ASKED QUESTIONS:
The 7018 rods are perfect for constructions which need a crack-free weld and high tensile strength. Especially if the weld requires dealing with a difficult to use metal as they help make the process smooth. These rods are usually used for low and medium carbon steel welding. The 7018 produces high quality, crack-resistant weld points.
As I mentioned above that the last two numbers indicate the flux coating of the electrode and the current which can be used with them. In this case the ‘18’ indicates that the electrode has a low hydrogen mixed with potassium and iron powder compounds. And the number ‘8’ indicates the medium penetration capability. This also indicates that the rod can used with, DCEP and AC.
The 6011 is regarded as one of the most versatile welding rods you can work with. The high penetration coupled with the ability to manipulate the arc makes it a top choice for a lot of people.
In a nutshell, both the 6011 and the 7018 rods are great choices in their own regards. There are some differences like the tensile strengths and the penetration effect but overall, they both are regarded as great electrodes. You might have a tough time handling 6011 while welding especially if you are a beginner but on the other hand the 7018s are difficult to handle while storing them. I hope this article made your decision-making process a little easier.