I’m brand new at welding. I recently finished my first welding project. I mig welded mitered edges and it turned out looking like this. Like a giant caterpillar of metal that I had to grind down.
When welding two flat surfaces together should I bevel the edges in order to make room for the filler material? Does it look like I should slow the feed or change the voltage or something?
Just a rooky looking for tips, thanks!
The wall thickness is probably thin enough you’ve gotten full penetration and that what is key. Overall, the quality of the bead looks good: no porosity is good… To ensure the welded angles are at max strength be sure to weld the inside and outside angles shut also so the box is sealed shut. These inside and outside joint as this is where the highest load are likely to occur plus it will keep debris/moisture from getting inside.
If new to welding I’d suggest cutting pieces of the tubing into 2X-3X width of the tubing and practice welding these together. You’ll be able to complete see inside and if the weld has penetrated. If you can see any of the original cut seam wall (not just where it was) then you didn’t get full penetration. If the seam is “filled in” or fused together then it is fully fused.
Grinding off the bead flush is a common practice, but if it isn’t fully penetrated then the joint is weak.
I personally find welding thin wall more difficult with burning through (.030<) than thicker materials. Above .100 I might start putting a light bevel, the thicker the material more bevel so you are filling in the bevel rather than trying put a lot of heat into the metal to penetrate all the through.
If your weld is all the way through, then the heat affected zone seen in you weld is pretty good
For thicker pieces where there is access to both sides. In only from one side, then bevel deeply and fill it with filler.
Try lower voltage and wire speed and you have to move pretty fast but not faster than the puddle will flow. I often times leave a small gap between parts when tacking to ensure full penetration. TIG welding will also give you a prettier weld with less grinding. I hate the noise and mess of grinding so avoid it when I can.
Also we use .035 wire, .023 or .030 would be better for thin gauge but you will also need the tips for that size wire. I have wire and tips to try but we have company so i wont have much free time till mid next week. Don’t buy cheap wire, there is more spatter, I like Lincoln superarc L-56 wire
That you for the explanation! So it seems that the bevel is more for thicker material in order to get optimal strength.
After I took this picture I welded the other inside the other four sides and tried to make sure there were no holes or gaps in the weld.
This is really informative, thank you very much!
Great advice. I’ll try lowering the wire speed and voltage on some scrap materials to see if I can make the weld a little smaller. I’m a little intimidated by TIG but I’ll definitely be looking out for a class as it is a skill I eventually want to develop.
Great advice on the thinner wire. I’ll have to give that a try as well on my next project.
I also don’t like the grinding. I hope to have to grind less as I improve my skills. Part of the improvement is coming from your thoughts, so thank you!
