How to properly weld on a moldboard

Hello all,

I have a slat moldboard on a #8 little
genius plow which has some broken slats.
What is the proper way to weld it? I have
access to both MIG and arc welding. I would
like to use the MIG wleder if possible.

Thanks!

Don't know if this is the "right" way. But I would 'V' the two halves,Clamp them together in the correct arc.Preheat . then lay in a root of 6011,thouroly remove slag,then fill with 7018.Remove the clamp and weld the flip side. Let cool naturally.Grinnd smooth.For more strength,weld a gusset on the back side. Weld only along the edge,do not weld across the slat/across the grain

The correct way to "weld" broken plow parts is to replace them, but in this situation where the parts are difficult/expensive/impossible to find replacements for, what have you got to lose? It's not like you're going to go out and plow 100 acres with it.

I've personally had luck welding coverboards back together just matching up the break and welding with 7018 on a high amperage setting, but those don't have much stress on them normally.

Treating it like cast iron as described above is probably the safest way and gives you the most chance of success.

First, make a heat sink, something to back up the slats and absorb the heat to avoid burning through the slats. Steel will work, but a 1/4 inch thick piece of copper will be best, if available. Grind entirely through the slats and clamp to the heat sink. Weld with 7018 rods or nickel. Grind the welds to smooth out and paint. Ellis

Thanks for the replies everyone. So it sounds like the MIG welder shouldn't be used for this process....

I will try my best. Grinding a weld doesn't make me a "welder", it makes me a "grinder"!

Years ago my dad broke a 2 bottom plow we had. He took it to a neighbor who was pipe line welder back in the day. On the front side he almost made it look like it had never been welded but on the back side if did not touch it so as to keep it stronger. A lot depends on what type of metal it is as to what rod to use. Also grinding a V in the break area is a very good idea. I know I would weld up a plow is I needed to but I have been welding for decades

Sometimes you have to grind. In your case,you have to grind a 'V' for peretration. Then you have to grind the 'face' smooth so dirt will flow,so the plow will scour. Then if you put a gusset on the baxkside,you grind the weld flat so the brace will lay flat.Haveing to grind a few things doesn't make you a 'bad' welder.Sometimes you grind,not to cover up a poor(birdpoop) weld,you grind to get a flat smooth surface.

Of course, I understand that. I was simply reiterating a welding joke I once heard. Thanks for further input DeltaRed.

You can use a mig welder to do this job. It is a matter of using the proper wire and the proper shielding gas. Any 70S-6 wire and 75%Argon/25%CO2 will produce the same weld as a 7018 welding rod. The 70 represents the tensile strength, the 1 represents position (All), and the 8 designates low hydrogen. With the 70S-6 wire, the 70 is tensile, S just means solid wire, and the 6 is chemical properties. Both methods produce a 70,000 tensile weld. The biggest factor you need to know to make the welded area as strong and ductile as the original metal is to find out what the original metal actually is. Because we probably don't know the answer to that, I would recommend welding with a dual shield flux core wire with 80,000 tensile strength and 2% nickel. 75/25 gas. The 2% nickel will give you the ductility needed and the 80 will give you a good tensile strength. So you are looking for 80T-Ni2 wire. Several companies make it, I prefer Select-Arc. Made in Troy OH, USA. Another tip, preheat the metal to 350 degrees to remove hydrogen and allow equal cooling rates. Hydrogen entrapment causes most cold cracks. Think of it this way, its not factual, but a good way to think about it, when you hit a cold piece of steel with a torch you see water on the steel. Steel is not a sponge, it does not have water in it, but what makes water? H2O!! Hydrogen hits oxygen and boom! Grind a groove that will allow full penetration, weld front side, back gouge the back side to sound weld metal and back weld. Only grind off the reinforcement you need to for proper function. IF the weld is made properly, there is no need for backing or a gusset. Not feeling like your welding skills are top notch? add a backing bar and weld it solid, or add a gusset!! If you need any help feel free to message!