I recently had a weld fail, which never happens to me I don't think I got enough penetration. If your not undercutting and the bead shape is good, does it hurt to turn it up? Talking 3/8.
It depends on what you are welding and what you are using
Sometimes welds fail because they were never engineered to hold the forces that are applied other times its just bad weld
did the weld break or the metal next to the weld? what material was you welding? what rods/wire? really need a little more info before anyone can give a good informed answer tho,,
3/8" rod is huge! Generally you will want your decimal equivalent as in 0.375 or 375 amps. Some machines weld hot/ cold. When I was at one job you could tell about 15 minutes before breaks you would have to turn your settings down.The best I have done is 5/32" 7018. They say that you will get Carbon migration to the sides of your puddle. I have only had two welds crack one was the wrong rod needed 11018 worked beautifully. The other didn't have much weld on the old chain and the other link is still holding, 30 years later.
Yes, to high an interpass temperature can weaken the metal in the Heat affected zone next to the weld. Then when the weld pool cools it can induce cracking next to the weld.
I believe he was talking about 3/8"material not rods..
More info.... otherwise this is a "how long is a piece of rope?" questions...
Mig welding. .045 co2 flux core. Mild steel, grade 80, T-1, AR400. 1/8 up to 1". I haven't been able to find a good voltage/material thickness chart, just used trial and error over the years. I've been playing around with lower voltages recently, guess I got my answer. The piece was a KW s-cam bracket which holds the springbrake can. I've welded 3 over the years and they're still holding. I replace the ones on the steer axles. I was just wondering if there are some general changes in weld properties at different voltages, penetration being one. PS, the break happened at the edge of the weld.
Failure right at the edge between the weld and the parent metal would most likely be put down to a lack of penetration. Without seeing photos that is...........
Get the recommended settings for the wire you're using, usually available off the web from the wire manufacturer. Usually a pretty narrow range on voltage for a given wire size. I generally use a mix like 75/25 rather than straight Co2, you get a more fluid puddle and slower cooling. My typical error is trying to go too wide in a single pass which lessens penetration in the root of the weld. I'm currently running Lincoln Ultracore 71A85 and love it.