Newbie stick welding question

Hi,

The other day I was welding 20mm by 30mm and 2mm thick angle iron bars to each other. The resulting thing will be a frame to place my table saw on. I have used 3.25mm 6013 rods with a current setting of about 125 Amps. But when I started to weld the 30mm side of the bars, the first 15 or 20mm was good, but then I was consistently burning a hole through the wall of the angle iron. So I started to weld in two steps. I first weld

15mm, let it cool, and then weld the remaining 15mm. This worked out quite good. The only disadvantage that I have noticed is of course the more ugly looking weld. Is this practice of welding step by step and let it cool in between right, or is something else wrong?
Reply to
Timur Aydin
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I think that if you used 3/32" 6013, at maybe 60 amps (just guessing), your burn through problem may go away. Here your welding rod is thicker than your material.

i
Reply to
Ignoramus19289

Hi Timur, all

Here is how you can see Iggy's suggestion is correct...

In general for electric arc welding processes you want about 40Amps per millimetre material thickness. So for your 2mm material you'd be starting your thinking and trying at around 80A. Now because you are welding small section angle iron the heat can't conduct away much (compared to a big sheet of 2mm steel), so you are going to want less current for a weld which is still well-fused.

Say you guess you'd start trying at about 70A. What size of rod is in its ideal operating range at 70A? That would be a 2.5mm diameter welding rod, as Iggy suggests.

Richard Smith

Reply to
Richard Smith

Thanks a lot for the responses guys, very helpful indeed :)

Reply to
Timur Aydin

Richard, you got the right idea but the wrong end. Amperage is usually calculated by rod diameter, not parent metal thickness. If it were you'd be using something like 1,000 amps to weld a one inch plate....

Reply to
jbslocum

If it was me, I'd use a different rod. I am partial to 7018 and 6010. If you are burning through, you have one of two problems. Either too big a puddle, or heat is too high. Ugly welds are caused by several reasons. One is the deposition of too much filler. The other is incorrect motion. Another can be that the base metal has paint, rust, oil, dirt, water, or some other contaminant in it. The materials you are trying to weld together should be no problem. What caused you to select the 6013 in particular?

Steve

Reply to
SteveB

Hey, you learn by doing a lot of crappy welds. And then getting some input. Ask any weldor.

Steve

Reply to
SteveB

Sorry, I forgot to mention that using too large a rod can cause burnthrough. When you get to where you can do it in your sleep, you assume that people know more than they actually do.

Steve

Reply to
SteveB

When I bought the welding machine, I was given a pack of 2.5mm and

3.25mm 6013 rods. I used up all the 2.5mm rods, so 3.25mm is what I have left.

Regarding contamination of the angle iron, when I first bought these, they were covered with some kind of a protective black grease. I removed this (or I thought so) layer using a rag and gasoline. But I remember having a hard time letting the first welds adhere to the metal. I was depositing a lot of rod and when I take my hand away, the angle iron was just dropping to the ground. Subsequent welds didn't have this problem. Maybe the excess grease just evaporated because of the heat.

The motion that I use during welding is a zig zag motion and I advance the rod towards the direction that it is tilted. In other words, I hold the rod in my right hand, let the tip of the rod point to the left side and move my hand to the right side. Because I am a perfectionist, I usually end up touching up the ugly welds with my OA setup.

Producing good welds with stick is really difficult. I now have respect and appreciation to the experts here and when I see a welder on a construction site doing his work :)

Reply to
Timur Aydin

OK, I understand it's time to get another pack of 2.5mm rods :)

What difference would it make if I were to use 7018 or 6010 rods?

Reply to
Timur Aydin
7018 is a great rod for many mild steels and HS steels. It runs smooth, gives decent penetration with a good bead profile. That said, the weldor's actions have a lot to do with getting good penetration and bead profile, too!

In the shipyard, we use 7018, 8018, and 11018 for almost all of our stick welding. Sizes range from 3/32 inch to 5/16 inch.

I would recommend using 7018 for most of your mild steel welds.

6010 is better if your base metal isn't as clean as it could be, use a "whipping" motion. Imagine flipping a lightswith on and off with your welding rod.

The first two digits in the number represent the tensile strengh of the deposited weld in PSI. Hence 6010 is 60,000PSI and 7018 is 70,000PSI.

The only drawback to 7018 is that you need to warm it up before welding. Bake the moisture out of it in an oven at 250 degrees for several hours if it's an open can of wire. For a new sealed can, you can go right to work.

Humidity affects the higher strength fluxed welding wires more than it will the 6010. Higher strength wires will be prone to hydrogen embrittlement and cracking welds if you use them without ensuring they are dry as a bone!

sorry for the rambling on- my only excuse is lots of painkillers.

Reply to
TinLizziedl

Try holding the rod in your right hand, and using a gentle weaving motion, feed the rod into the puddle. Remember, the puddle is ALL. Ofen people start welding thinking that they control the puddle. As it turns out, the puddle also controls you! Usually, Dragging the puddle along the work gives a better weld than pushing it, but everything is dependent on context.

Grab a chunk of ordenary steel. Clean the crud off until you have bright, shiny metal. Snag a weldor and ask them to run a bead while you watch. Don't just stare at the puddle, watch how they set their body, too. Then you do it. Try to match their bead. You'll be lightyears ahead of where you are now in mere minutes.

Later will come the nuances of controlling heat input to specific applications. Speeding up, slowing down, sizes of welding rod, style of application (forehand, backhand, whipping,...) selecting an amperage that suits rod and material, The list goes on and on....

Reply to
TinLizziedl

Timur, it is not difficult for everyone, it is only difficult until someone showed you how to do it and you get several tens of hours practice. Get some steel garbage and a couple of boxes of welding rod, and get some practice.

igor

Reply to
Ignoramus30026
6013 is a drag rod, it needs no weave at all. Just run the rod close to right angles to the weld, fairly close arc (about the thickness of the rod), and move slowly forward. You should get a bead about 2/3rds as long as the rod making the bead.

As for rod selection, (in spite of other comments about 6010 and 7018),

6013 is a very nice rod for newbies. Nice bead, moderate penetration, easy slag removal, no rod storage problems, easy to handle puddle. A downside is that 6013 is not as aggressive as 6011 or 6010 in burning through rust, oil, grease, and assorted other crud. It should handle a mild oil film with no issues.

Your orig> SteveB wrote:

Reply to
RoyJ

7018 is a great rod, but I would not recommend it to you. The 70 in the number is the strength. So 70 is stronger than 6010, 6011, or 6013. But so what. you are not welding anything with a strength close to 60. So having the weld stronger than the material you are welding makes no sense.

Second 7018 is a low hydrogen rod. Not having hydrogen disolved it weld is important for high strength steels. To protect the molten puddle, 7018 has a flux that lets the rod burn back inside the flux, so the flux protects the molten metal better than flux that burns off and exposes the end of the rod. But the disadvantage is that you have to break off some of the flux in order to restart an arc on 7018. Not a huge deal, but an annoyance just the same.

And some 7018 only works well on DC. Some works well on AC, but you have to make sure that any that you buy will work on the welder that you have.

If you are welding mild steel, having moisture in the flux of 7018 in not a problem. But if you are welding high strength steel , just baking the rods before welding will not hack it. You need to keep them in a rod oven when ever they are not in a sealed container.

I am assuming that you have a AC welder. Nothing wrong with that, but some rods as 6010 are intended for use on DC welders. So buy some more 6013. It should be slightly cheaper than 7018.

=20 Dan

Reply to
dcaster

I suggest you go to the welding site for the brand of rods you use. 7018 is a 70,000# tensile strength rod, all position, with an iron powder coating. It deposits metal at high rates. It is used for lots of applications, but mainly where you want a strong good looking weld. 6010 is a 60,000# tensile strength rod, all position, cellulose coating, IIRC. It is used for root passes, and to get dirty metal to stick together.

The two have very different handling characteristics with regard to hand motion, length of arc, sequence of bead placement, and other things.

6013 rod is commonly used for sheet metal and thin metals. It lays on the surface more than these other two. 6010 and 7018 is for when you want to really burn it in for fusion and penetration. Get some and play with it. Once you master 7018, you will find yourself using it a lot. 6010, too.

Check those company sites, as they may give you directions regarding whipping motions versus staying in the puddle that may be the cause of your having ugly welds..............

Steve

Reply to
SteveB

Application of OA after the weld is complete will give you a much larger heat affected zone, weakening the weld. Learn to use the right rod. Are there any local community college type courses in your locality?

Steve

Reply to
SteveB

First, the disclaimer: I am a welding amateur - I have no training & little experience, although I've had my tombstone for 20+ years. I use a pound or two of rods a *year*, making little projects.

I only ever use 6013. It is easy & it works. 6010 is said to penetrate better, but it sticks more. 7018 is said to be better for some reason, but that screwing around keeping it dry is way more trouble than I'm gonna' do. 6013 is said to need clean metal, but I don't worry about that much & it works.

YMMV, Bob

Reply to
Bob Engelhardt

My welder is a simple 250A DC inverter. It's an ExpressWeld 250, Lincoln's low end, chinese made welder.

People here had suggested me to get a MIG welder, but those are much more expensive here. And I have also read on this group that a MIG welder lets you make very nice looking welds, but if the settings aren't right, the penetration will not be right and the weld can break easily.

Reply to
Timur Aydin

I might as well get all three types and experiment with my stock of junk metal...

Reply to
Timur Aydin

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