*Welding Rods*
Disclaimer: This is part of a basic welding for the homesteader/prepper series I'm doing. It's not in any way intended to make you a good, decent or certified welder. Becoming a certified welder takes time, patience and passing national tests. The "bubblegummer's" philosophy of "a grinder makes a bad welder look like a good welder" doesn't hold true. Not knowing how to weld correctly can result in catastrophic disasters. This is merely informational about a few rods that you might choose from. If you want to get in to basic welding I suggest getting somebody to teach you or taking some night classes.
True story-I've seen some less than desirable welds. Recently a young guy bombed a simple bend test. The test was simple. MIG weld two 22.5 degree beveled plates with a backing strap together in the horizontal, vertical and overhead positions. Then cut out two coupons from each and bend them. His MIG machine amperage was set WAY too low (about 90- I put mine in with around 180 amps on a vertical and about 200 on a horizontal and overhead) and he gobbed in a root and gobbed in passes. When he bent them they broke. He spent two days cutting the test plates out of a large flat plate and grinding them down to the required size. Then he completely screwed himself so all of his work went to nothing.
So think of somebody like him who doesn't know how to do things properly and does it anyway. Seriously, he didn't know how to set up and adjust a MIG machine. What if that weld was on something like a trailer, a trailer hitch or something structural? It looked like crap, but grinding it down makes it look better. Looks aren't everything. It HAS to be good. That's why it takes so much to become a certified welder and even then, working for a company they have their own tests which are often more strict.
Stick Welding
Stick welding (shielded metal arc welding) a.k.a. SMAW is performed by using a consumable rod (electrode). There are some different diameters such as 3/32", 1/8", 5/32", ¼". The diameter doesn't necessarily determine what the rod is to be used for. Typically 1/8" will handle most applications that you would get in to around the homestead. Other diameters have their place. For example, when welding a pipe together it'll likely get a 1/8" 6010 rod for the root and then the rest with a 3/32 rod. That's one way.
What's a 6010 rod? Well, rods are labeled with a numerical code. If it's intended for electric welding there will be an "E" before the numbers, ie E-6010.
Here's a few numbers:The first two or three digits, depending on how many digits are shown are the minimum tensile strength of the rod. Multiply it by 1,000. So a rod that is 60XX will have a minimum tensile strength of 60,000 pounds per square inch. 70xx is 70,000, 80xx is 80,000 and the 110xx is 110,000. The next digit will be either a 1 or a 2. 2denotes that the rod will weld in a flat or horizontal position. You can't weld verticals or overheads. 1 indicates "all positions" so it'll go inside, outside and upside down. All positions means exactly that. You can weld overhead, which means upside down.
The last digit is a manufacturer specification describing the characteristics of the rod. Using a chart you can determine if the rod is designed for AC, DC either polarity, DC-, DC+, AC or DC. It also tells if the rod is designed for shallow or deep penetration and whether or not it's a fast deposit or not. There are more characteristics described.
Terms-A 6010 (aka pipe welder's rod) is a fast freeze rod and doesn't run like other rods. It's used in a whipping motion where the welder has to move the rod in and out of the weld pool while maintaining an arc. The weld pool quickly solidifies when the arc is moved out of it. That's why it's a fast freeze. It's used for doing open roots, which means having to weld thin air. When joining a pipe there will be a gap of some dimension between the two pieces. An 1/8" gap can be filled in with an 1/8" inch 6010 rod. This is known as the root and to pass the pipe welding test, the root on the inside of the pipe has to be smooth with no porosity and pass a bend, X-ray or ultrasound test.
Using the proper rod with the correct amperage is critical. As I was taught "weld with as much heat as you can handle".There are charts that will specify XX amount of amps for XX thickness of metal with XX rod. That's all good and fine except that not every welding machine is exactly the same. One might say exactly 150 amps and be producing that and another could say 150 and you're actually only getting 140. Of course, dealing with DC it doesn't travel well over distance so the longer the welding leads, the more loss there will be. A machine with 2/0 leads will work differently than with 1/0 leads. So maybe that machine that's set at 150 amps and producing 150 amps will do so with 6' of 1/0 cable. Now what happens when another 20' of cable is added on? You aren't getting the 150 amps to your stick anymore! It boils down to knowing how to read the weld pool. You have to use what works, not what a chart says.
Here are some various rods that I happened to have opened up-
So what do we have here?
8018- 80,000 PSI tensile strength, all position. The last 8 denotes "AC or DC+, iron powder, low hydrogen, fill freeze, shallow to medium penetration, high deposition, easy slag removal, convex beads.
7018- 70,000 PSI tensile strength, all position. The last 8 means the same as above.
6010- 60,000 PSI tensile strength, all position. The last 0 denotes DC+ only. High quality deposits with deep penetration and flat or concave beads, cellulose sodium coating (these things stink like burnt toast and paper.)
6011- 60,000 PSI tensile strength, all position. The last 1 denotes AC or DC+. High quality deposits with deep penetration and flat to slightly concave beads, cellulose potassium coating.
7024- 70,000 PSI tensile strength, flat or horizontal position. The last 4 denotes AC or DC either polarity, fast deposition rate, deep groove butt, fillet and lap welds, medium penetration, easy slag removal, iron powder, titania coating. (This is a FUN rod to run but produces a LOT and I mean a LOT of smoke. If your helmet is over top of it it's just gonna smoke up the lens in a few seconds and you won't be able to see anything. Stay out of the smoke.)
Bad Stuff!!!
Moisture is your enemy. Using old rods that don't even look good or leaving them in damp locations will screw you. Using rods whose case has been opened and sat on the shop shelf for 2 years collecting airborne dust and grime isn't good. Keep them DRY and clean. Any contamination on them will go in to your weld. On some code welds the rods are kept in a hot box and are only allowed to be out of it for 5 minutes. If the rods aren't used in that time, they have to go back in.
Flux
The coating on the rods is called flux and while welding it vaporizes creating a cloud. This cloud (shielding) keeps atmospheric contaminants out of the weld area. Welding in windy conditions can cause that cloud to be blown away and a bad weld will be produced. The slag left on top of the bead is from the flux also. Its purpose is to keep the weld from cooling too quickly. The 7024 produces a lot of slag. NEVER use damaged rods where there are chunks of flux missing. If a rod ever looks questionable, don't use it. If you do when you get to that point on the rod the shielding cloud will be greatly reduced and create a bad spot in the weld.
Eli
www.alpharubicon.com
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