7018 use on cast iron

[Arc weld]

Using brass/bronze filler would have similar properties to cast iron but cast steel is much easier to weld than cast iron with common welding rods and wouldn't require the heat needed for brazing.

 

[gwdixon]

Arc (and others), I didn't go with the brazing method partially out of inexperience with the process and partially because the piece will be subject to ground impact in the rocky soil around here. It may have been the wrong choice. We will see.

Things such as leaving the weld built up causing problems down the line is also new to me. But so is dealing with cast iron and cast steel. I'm usually more involved with welding up something like a broken disc frame or fabbing some part to make a solution for something that comes to mind while sitting on a tractor all day.

I agree that the piece came out "ugly". The welds are far from "pretty" like a pro would do. Even I can spot mistakes here and there. Thanks to all for being gentle with an old guy's attempt at a fix.

The paint was to make the piece blend in with the flail mower and not be so noticeable.

 

[Gary Fowler]

If you can get a weld to hold it will be much stronger than a brazed weld (using brass alloy) so I think you did the right think. I suspect that piece is cast steel rather than cast iron. Cast iron is used mostly for stuff subjected to heating and cooling like fire grates, engine blocks, manifolds etc because it doesn't expand and contract as much as steel and doesn't rust up when heated as bad as steel or cast steel. Cast iron also doesn't take to shock loading at all, so anything bolted on is likely cast iron. When broken, cast steel is a light grey color where as cast iron is more darker grey with black flecks in it.

 

[CalG]

If you can get a weld to hold it will be much stronger than a brazed weld (using brass alloy) so I think you did the right think. I suspect that piece is cast steel rather than cast iron. Cast iron is used mostly for stuff subjected to heating and cooling like fire grates, engine blocks, manifolds etc because it doesn't expand and contract as much as steel and doesn't rust up when heated as bad as steel or cast steel. Cast iron also doesn't take to shock loading at all, so anything bolted on is likely cast iron. When broken, cast steel is a light grey color where as cast iron is more darker grey with black flecks in it.

The good part about any repair is that it doesn't need to be "the strongest", just stronger than the parent metal next to it ;-)

(No HAZ with brass, but the part can not be welded after trying to braze it. That's a bummer)