If you’re just getting into welding, you may have a few questions about what type of welding rods to use. This is a very important step in any project. There are so many beginners out there that will just grab the first welding rod they come across thinking it doesn’t matter. Selecting the wrong welding rod can cause multiple problems. These rods range anywhere from a weak joint to damaging the material you’re working with. If you’re anything like me, you have to make sure that every project comes out as aesthetically pleasing as possible. The more pleasing it is, the more likely it is to sell. selecting the proper welding rod to work with the project you’re doing is a big part of this.
When I first started welding, one of the problems that I ran into was not being familiar with the classification of each welding rod. It took me a while, but I finally found some information on what the codes mean and how to interpret them. That’s one of the reasons I’m writing this article. I wanted to pass on some information and hopefully be able to give you a better understanding of “The Craft.” Selecting the proper welding rod to use with your machine and your material is an imperative part of the process. Once you understand the classification of the rods and the types of machine that you have, it will help you pick which of welding rods that would be appropriate for you to use.
What Does the Welding Rod Classification Mean?
Let’s take a look at the welding rod classification sequence and see what the different sections mean. The first digit indicates what type of welding the rod should be used for. This will normally be an E which designates it is used for arc welding. The first two or three numbers will indicate tensile strength. This is how many pounds per square inch the material can withstand without being pulled apart. The third or fourth digit designates which position should be used for welding. The 4th or 5th digit tells you what type of coating the electrode has and what type of power supply to use with it.
As an example, let’s break down the classification E6010. The E as stated indicates the rod should be used for arc welding. The next two digits indicate it has a 60,000 pounds per square inch tensile strength. The one indicates that it can be used in all positions and the zero indicates that this type of rod should be used with a DCRP (direct current reverse polarity) machine. While it can be a bit of a challenge to figure all of this out. after you’ve done it a few times you will become a deft hand at it.
Which Welding Rod to use for Which Metal
Wrought Iron: E6010, E6011, E7014, E7018
Cast Iron: This type of metal requires an NI-CL electrode
Steel: Many rods between an E6010 up to E7024 will work depending on the type of machine you have.
Stainless Steel: E308L
Aluminum: E4043
If you are looking for a different result due to imperfections you can experiment some and see if another electrode will give you a better look and finish. There on many different opinions on which is right or wrong. These are the electrodes that the majority recommended though. If you are looking to weld other materials, there is a welding rod out there for just about anything.
The Different Types of Electrodes
Bare Electrodes
This type has no coating on the outside other than what is required when the electrode is drawn at the factory. This type of electrode is designed and made for specific use. IE welding manganese, steel, and other metals like that. With harder steals, having a coating on the outside of the electrode is undesirable or not needed.
Cost
The price of welding electrodes can vary heavily from one retailer to the next depending on the quality of the product. I took a look at a few different sites to judge and approximate price for the three different styles of welding electrodes. Bare welding electrodes tend to range anywhere from $4 a pound all the way up to $49 a pound. Depending heavily on the type of electro that you’re looking for.
Difficulty Level
This type is welding rod requires a higher skill level when it comes to arc welding. I would not recommend this type of welding for an amateur or beginner. They require intensive training to use effectively and safely. This type of electrode is typically used for the harder metals and should only be used for the intended material.
Storage
It may sound counter-intuitive, but bare welding electrodes should be kept in a dry place. Moisture can compromise any kind of coating on the metal and can even cause damage to the metal itself. This damage can cause pitting and cracks in the weld area when trying to achieve a smooth surface. With this type of welding rod if the electrode does get damp, it is easier to dry them off than it is with the coated electrodes. All you have to do is dry them and then move them to a humidity-free area. Having said that, if you noticed damage to the electrode, this can cause multiple issues and you may want to consider replacing the rod.
Lightly Coated Electrodes
Listed under the E45 series in the classification system, a light coating of material is applied to the electrode with numerous different techniques to improve the arc stream characteristics. It does this by introducing ionized materials into the stream. While this type of electrode may produce a small amount of slag, it will not act the same way as the slag produced by shielded Arc electrodes. These electrodes are typically used for welding molybdenum, iron, manganese oxide, nickel, and chromium.
Cost
Lightly coated welding rods do not typically cost as much as the bare metal electrodes. A pound of the e6010 welding rods cost around $1.50. In order to get an accurate price, I would do a little research on exactly what metal you’re going to be welding. Figure out what kind of rod you need for that particular metal and price it at that point. The price of these rods vary heavily depending on the type.
Difficulty Level
While these electrodes are not as hard to use as the bare metal electrodes. They do still require quite a bit of training. The metals that these electrodes are designed for are harder to weld than the average. They can be a bit softer and this will cause you a problem. However, with some training and a bit of practice, you should be able to master this style of welding.
Storage
This style of welding rod has a light coating of material covering the electrode. This material is susceptible to moisture in the air or in the environment. As stated above, you really don’t want to let moisture get into that material because it can cause cracks in the weld, pits, and splashing of the material. If moisture does get into the material surrounding the electrode, there is a way you can dry it, but you will need an electrode oven. The lead should be baked in the oven for 2 hours at 500 degrees Fahrenheit.
Heavy Coated or Shielded Arc Electrodes
As the name implies, this welding electrode is heavily coated. The material that these electrodes are dipped in is typically a type of cellulose, minerals or combination of both. The molten material creates a gaseous zone around the arc that protects the weld zone. This type of electrode is typically used to weld cast iron, hard surfacing or steels.
Cost
This type of welding rod is used on more typical types of metal. The coding is thicker to help create a gaseous zone around the weld. They normally run between $4 a pound up to $40 a pound. depending upon the type that you need and what kind of coating is on the outside.
Difficulty Level
These are some easier welding rods to use, but you should always have training in the field before attempting to weld. Especially, if you’re looking for the desired result. While these are some of the easier rods to use, they still require a certain technique that should be learned.
Storage
The coating on these being heavier is more susceptible to moisture than the bare or the lightly coated ones. If moisture is introduced into the material, you will get effects such as pitting in the weld, cracking or splashing of the material. Like lightly coated electrodes, they should be stored in a dry place with no humidity. If moisture is absorbed into this type of electrode, you can dry it out using an electrode oven. bake the rods at 400 degrees Fahrenheit for 2 hours. This should be sufficient to dry out the coating.
What are the Different Coatings on Welding Rods?
EXX10
This is one of the more common types of electrodes and is highly used. It has a cellulose-sodium coating that helps it create a carbon dioxide gas shield around the weld area. This produces deeper penetration into the material you’re working with. The coating is a type of cellulitic material formed from wood flour. Some of the reprocessed electrodes that have low alloy also use up to 30% paper.
EXX11
While fairly similar to the cellulose sodium electrode, this type of electrode uses cellulose-potassium. This adds ionization to the arc and makes it more suitable for use with alternating current. That means that the penetration, Arc action, and weld result are similar between the two electrodes. With this kind of electrode, they stabilize the arc using small amounts of iron powder. This in turn ramps up the deposit rate.
EXX12
This type of welding rod will have high levels of titanium oxide or Rutile content in comparison with the other components. Using a Rutile-sodium coating, this is an appealing electrode because the coating causes a slag that is easily controlled, a quiet Arc, and very little splatter. The weld deposit on this type of electrode has a smooth surface and low penetration. If you compare this to cellulose type of electrode the weld is much more desirable. This type of electrodes can be used with either a direct current or alternating current. It does this requiring a small amount of Arc voltage compared to other electrodes.
EXX13
While this is a similar electrode to the Exx12, it uses rutile-potassium instead of rutile-sodium. This causes less arc ionization making a smoother weld. This type of electrode is more suitable for alternating current. however, it is possible to use it with a direct current welder of either polarity.
EXXX4
While this coating is akin to the rutile coatings listed above, it uses rutile iron powder. If the iron content range is between 25% and 40%, it is considered an Exx14. If there is 50% or more of the iron powder, the electrode is considered an Exx24. This means that the Exx14 can be used in any position and the Exx24 can be used in the flat position or to make a fill weld. Depending upon the amount of iron powder that is added, it will increase the deposit rate.
EXXX5
This rod has a low hydrogen-sodium coating. Any electrode that uses calcium chloride or calcium carbonate are considered low hydrogen, basic type electrodes or ferritic. meaning that asbestos, clay, cellulose or any other mineral that combines with water are not used. Doing this ensures the lowest possible hydrogen content in the atmosphere around the arc. This will help stabilize the arc and give a smoother weld. They have a medium to moderate penetration of the material. The depositing speed is medium, however, they require certain techniques to be used for the best results. This makes this type of welding rod a harder rod to use until properly trained.
EXXX6
This welding electrode uses has a low hydrogen potassium coating. This type of coating is very similar to the low hydrogen sodium accept the fact that uses potassium so that you get Arc ionization. The electrode can be used with direct current reverse polarity electropositive. However, it is intended for alternating current machines. While it has a smoother action than the EXXX5 rods, the penetration of the two rods are very similar.
EXXX8
This type of electrode uses a low hydrogen potassium coating similar to the EXXX6 with one exception. This electrode has iron powder added into the coating. If the percentage of iron powder in the cooking is between 35 and 40%, the classification of the rod is considered an EXX18.
EXX28
This type of electrode is coated with low hydrogen iron powder which has high iron oxide content. This type of rod produces a weld with a large amount of slag. The deposit rate for this electrode is higher than the EXX18 and it should be used in the flat position or for fill welds. The fact that it has a low hydrogen coding means that it can be used for any of the higher alloy electrodes. Adding this type of material in the coding means that these electrodes become the types of alloys where suffix letters indicate the weld material. For instance, you would you use a low hydrogen rod to weld stainless steel.
EXX20
This type of welding rod uses an iron oxide sodium coating. It can be difficult to control because of a large amount of slag that is produced by the weld deposit. Providing a medium penetration with low splatter and a high-speed deposit, this type of welding rod leaves a very smooth finish. These electrodes can be used with either polarity from alternating current or direct current. It is meant to be used in a flat position or when making a fill weld.
Other Rod Coatings
While these are not the only types of welding rod coatings out there. They are some of the more common ones. Most of the other coatings you find will be a combination of these types. The other types of coatings are for specific uses such as cast iron welding or hard surfacing. If you are doing a project that requires a specialized welding rod, I would suggest getting in contact with the manufacturers to see what they suggest for that project. Ultimately, they will be able to tell you which one of their products is more suited for your need.
In Conclusion
While I was doing the research for this article, I came across many different aspects of welding rods that I hadn’t previously thought about. I always knew that certain ones were designed for certain things, but I never really delved into the different aspects of the coatings. Having said that, while I did know some things about welding, I can tell you that I have learned quite a bit about the different rods and coatings. Always make sure that you are using the correct rod and machine for whatever project you are working on and it will make the results much more appealing. While stick welding has been around for a long time, it has become somewhat of a lost art, so let’s bring arc welding back into the lime lite.