What the number system for electrodes means.


Matt Shade

One tip for anyone looking to buy a stick welder, is you need to learn what the number system for electrodes mean. Here's a basic rundown.
You have 4 digits-
The first two tell you the ultimate tensile strength of the core wire in 1000 psi. So 60 series has 60,000 psi and 70 series has 70,000 psi ultimate tensile strength.

The 3rd digit tells you the position the rod is meant to be used in.
1-all positions, flat horizontal, vertical, overhead, you can use it for any of them.
2-flat only (this stuff will run all over if you try and do anything else with it)

The 4th digit tells you the type of coating, which is important because it tells you what you can weld with it, and the type of transfer it will be. Digits go 1 through 9, but I'll only go over the common ones since I don't have any notes with me right now.
1- this is a spray transfer rod. It offers very good penetration and will run at lower amperage. Its not the best choice for thin material, or poorly fit joints. It also leaves a very large amount of spatter. This is a good choice for thick steel though.
3- this is a globular transfer. Offers less penetration, but lays a heavier bead. Also has reduced spatter from the spray transfer. you can run a very clean pretty bead with this stuff. You have to watch what your doing though as penetration isn't as deep.
4- This is a high iron content coating. It deposits a lot more filler for the given rod size.
8- This is a low hydrogen coating. Used in a lot of "code" applications, because hydrogen embrittlement can be a very serious problem with some materials.

So if you know that stuff, you can look at 6013 and know right off the bat that its core wire has a UTS of 60,000 psi, and its an all position globular transfer electrode.
7018 has a core wire with a UTS of 70,000 psi and is a low hydrogen rod for all positions. Its also a globular transfer. I'm pretty sure that all coatings except for #1 are globular transfer.
7024 has a core wire with a UTS of 70,000 psi and is a high deposition rod meant to be used in the flat position. This is going to have a very large and fluid weld pool.

Hope that helps somebody