martin_cho
Plastic
- Joined
- May 16, 2021
Learning how to MIG weld. I could use some feedback.
I've been practicing MIG welding in an effort to get better at it. Watched multiple videos online and spent a few hours consuming a full spool of 0.023 wire laying down beads in three dimensions (x, y and z), pulling, pushing and experimenting with different settings.
Equipment
Miller 130XP 120V welder, 75%/25% gas
Wire speed set to approximately 440 inches per minute (gas off, pulled the trigger for six seconds, measured wire, multiplied by ten). Voltage set to "4", which is the maximum setting. Those are the only two controls I have. I used recommendations I found online to choose wire speed.
Gas flow set to 25 CFH.
Wire
AWS A5.18 ER70S-6
0.023
The guy from Praxair recommended it. All I know about it is what I can Google. Not sure if this is the best option.
Material
1/8 nominal mild steel, brushed lightly with a stainless steel brush. While the material was clean, you can see what it looked like on the T assembly. Now I am thinking I should take a grinder to a few pieces and see how much different it might be.
Environment
Welding outdoors. A bit windy. I made a small shielded area with cinder blocks to try and keep wind from blowing off the shielding gas. This worked most of the time, yet, as can be seen in the images, whenever the wind got too strong I got popcorn. The effect was immediate. I tried to react and get the nozzle closer to the weld. Sometimes this worked, sometimes it did not.
The welder is rated at 90A 20% duty cycle. It is supposed to be able to make up to 130A. Right there I am thinking I was already operating at the limit for this machine. Not sure. In other words, I don't know if welding 1/8 steel with this machine is a plausible idea. I did take pauses for everything to cool down (machine and material).
PICTURE 1
Here I used all techniques I mentioned above, push, pull, x, y and z (clamped vertically) welding. The dots are intended to simulate tack welds.
The red circles are "wind events" that blew away the shielding gas.
Curious about the shinny spots, one of which is circled in green.
In general, please comment on anything you see and help me understand how to improve my welding. One of my challenges was keeping a steady hand. I was experimenting with different bracing techniques throughout. I was standing in front of my work surface, which was about waist high.
On the other side of this piece (which is about a foot long) I experimented with wire speed, voltage, stickout, gas flow, welding patterns (circles, "e", triangles, zig-zag, etc.) and welding travel speed. I built it up to a about a 1/4 of thickness before moving on. Not showing it. It's ugly.
PICTURE 2
OK, this was my "graduation" weld (one of two) after most of the spool was gone. Again, I am looking for critique and guidance on this. A friend told me the weld is cold. While this was glowing red hot as I welded, after some research I think this means I simply didn't have enough current and the weld bead needs to be flatter rather than convex (rounded out) as it is. This is what made me think I might need to get a larger machine due to the limitations of this one.
While I know this weld is likely structurally sound (I'll cut it today to look at penetration, etc.) I also know it could be improved. Just trying to figure out how.
All I did before taking this picture is take a few swipes with a stainless steel wire brush.
This is where you can see what the raw material looked like before welding. As I said above, I want to repeat some of this work after taking a grinder with a flapper disc to the surfaces.
PICTURE 3
On the other side of the same "graduation T" I attempted a bead on top of a bead. Not necessarily thrilled with the results. The wind was blowing a bit harder, so I got some popcorn in places. Also, the same issue with the bead being rounded rather than on the flatter side of things. Not sure how I fix that. Is it the machine, settings, technique?
On the next training run I'll consume a spool welding 0.060 nominal material, mostly tubing. As a "graduating" project, I'll probably try to make a cube out of 1x1 or 2x2 0.060 mild steel tubing and force myself to weld in all orientations. My gut feeling is that this machine should be able to do well with such a project and any issues will be down to my lack of experience and technique rather than anything else. I am very interested in learning if my suspicions regarding the use of this machine for 1/8 material are correct.
General notes/questions:
I know that's a lot of questions. I probably have more. I am also hoping this might help other newbies in the future.
Thanks!
I've been practicing MIG welding in an effort to get better at it. Watched multiple videos online and spent a few hours consuming a full spool of 0.023 wire laying down beads in three dimensions (x, y and z), pulling, pushing and experimenting with different settings.
Equipment
Miller 130XP 120V welder, 75%/25% gas
Wire speed set to approximately 440 inches per minute (gas off, pulled the trigger for six seconds, measured wire, multiplied by ten). Voltage set to "4", which is the maximum setting. Those are the only two controls I have. I used recommendations I found online to choose wire speed.
Gas flow set to 25 CFH.
Wire
AWS A5.18 ER70S-6
0.023
The guy from Praxair recommended it. All I know about it is what I can Google. Not sure if this is the best option.
Material
1/8 nominal mild steel, brushed lightly with a stainless steel brush. While the material was clean, you can see what it looked like on the T assembly. Now I am thinking I should take a grinder to a few pieces and see how much different it might be.
Environment
Welding outdoors. A bit windy. I made a small shielded area with cinder blocks to try and keep wind from blowing off the shielding gas. This worked most of the time, yet, as can be seen in the images, whenever the wind got too strong I got popcorn. The effect was immediate. I tried to react and get the nozzle closer to the weld. Sometimes this worked, sometimes it did not.
The welder is rated at 90A 20% duty cycle. It is supposed to be able to make up to 130A. Right there I am thinking I was already operating at the limit for this machine. Not sure. In other words, I don't know if welding 1/8 steel with this machine is a plausible idea. I did take pauses for everything to cool down (machine and material).
PICTURE 1
Here I used all techniques I mentioned above, push, pull, x, y and z (clamped vertically) welding. The dots are intended to simulate tack welds.
The red circles are "wind events" that blew away the shielding gas.
Curious about the shinny spots, one of which is circled in green.
In general, please comment on anything you see and help me understand how to improve my welding. One of my challenges was keeping a steady hand. I was experimenting with different bracing techniques throughout. I was standing in front of my work surface, which was about waist high.
On the other side of this piece (which is about a foot long) I experimented with wire speed, voltage, stickout, gas flow, welding patterns (circles, "e", triangles, zig-zag, etc.) and welding travel speed. I built it up to a about a 1/4 of thickness before moving on. Not showing it. It's ugly.
PICTURE 2
OK, this was my "graduation" weld (one of two) after most of the spool was gone. Again, I am looking for critique and guidance on this. A friend told me the weld is cold. While this was glowing red hot as I welded, after some research I think this means I simply didn't have enough current and the weld bead needs to be flatter rather than convex (rounded out) as it is. This is what made me think I might need to get a larger machine due to the limitations of this one.
While I know this weld is likely structurally sound (I'll cut it today to look at penetration, etc.) I also know it could be improved. Just trying to figure out how.
All I did before taking this picture is take a few swipes with a stainless steel wire brush.
This is where you can see what the raw material looked like before welding. As I said above, I want to repeat some of this work after taking a grinder with a flapper disc to the surfaces.
PICTURE 3
On the other side of the same "graduation T" I attempted a bead on top of a bead. Not necessarily thrilled with the results. The wind was blowing a bit harder, so I got some popcorn in places. Also, the same issue with the bead being rounded rather than on the flatter side of things. Not sure how I fix that. Is it the machine, settings, technique?
On the next training run I'll consume a spool welding 0.060 nominal material, mostly tubing. As a "graduating" project, I'll probably try to make a cube out of 1x1 or 2x2 0.060 mild steel tubing and force myself to weld in all orientations. My gut feeling is that this machine should be able to do well with such a project and any issues will be down to my lack of experience and technique rather than anything else. I am very interested in learning if my suspicions regarding the use of this machine for 1/8 material are correct.
General notes/questions:
- I don't mind buying a newer/larger machine. I have 220V available, so that would not be a problem.
- What are the brown spots on the last picture? Is this bad? If so, how do I get rid of it other than grinding? In other words, is it a matter of technique?
- PICTURE 2: How important is it to shoot for a "stack of dimes"? I was doing an "e" pattern on this one. Not sure how to achieve dimes.
- Are the welds on the T structurally sound despite not looking professional? Is this something that can only be known through testing?
- Can I/should I, weld this material without grinding it clean?
- I was using 25 CFH for gas because it was a little windy. I can't weld indoors. Was that too much?
- Is a newer inverter-based machine going to be easier for me? The 130 is about 20 years old, I think.
- I learned that you need about 1A per thou. That means this machine can't really make it for 1/8 material. Right?
- How flat should these welds be? They are rounded. My friend led me to believe the T welds were "cold" because they are rounded. Is he right?
- Other than lots more practice (I got two more spools I want to burn through for learning), how else can I make my results more consistent?
- How important is it to have a relaxed grip? I had to stop myself from clamping down too hard while welding.
- What's the best working height? I was welding standing-up and the work surface was at waist level.
- Should I try a larger diameter wire?
- Is there a relationship between wire diameter and the thickness of the material you are welding? Is 0.023 too thin for what I am doing?
- Should I be using a different type of wire (using ER70S-6)? How do I select it? Where do I learn about matching wire to material?
- I there a different nozzle/setup that might make welding outdoors easier? I am thinking a welding blanket and three portable 6x8 ft shields.
I know that's a lot of questions. I probably have more. I am also hoping this might help other newbies in the future.
Thanks!