cast iron welding.....HELP!

I've tried both TIG and ARC w/ similar results, altho the rod I used was steel and silicon bronze.

Worked fine, just looked uguly and didn't go smoothly. This was on an exhaust manifold so contamination may have been an issue. I prepped very well.

 

I use a nickel rod with an arc welder to fix my cast iron. Of course there are much better ways, but it works for me. I clean the snot out of it, then sand blast the area, then clean some more. Then I heat it with a propane torch. You will see the water sweat away from the heated area as you are heating it up. If it is a exhaust manifold, I bolt it to a head before I start heating it. Once I have the bead finished I cool it down slowly. Of course here in Houston during the summer, nothing cools off very fast hehehe.

The key for me with the nickel rods, is this. Every time you strike the arc, you are depositing lots of flux in the area. You cannot strike the arc, then let up, then strike another arc without first cleaning off the flux. The flux on these rods is very hard, and it cools very smooth. You must chip it, and wire brush it off before striking another arc. If you dont, the flux will be trapped between the beads, and will crack. So if you run a bead, then stop. Chip it, clean it, and heat it before you continue the bead. Once you are happy with it, cool it down slowly and you should be good to go.

I have used this method to fill some pretty large holes. I lay a small bead, then chip, clean, heat, and lay another bead. Once it is filled in, I dress it with a die grinder or belt sander or whatever will fit the area.

Here are a few pics of a manifold that had a chipped off ear. I built it up with small beads, chipped, cleaned and heated between each arc. It takes a very long time to do it this way, but works for me.

-Dave

Start of the fill. Just small tacs to build up the area. I clean up the small voids and bevel them before adding more beads to it. I also grind out any cracks or flux lines I find during each stage. Building up slowly until the area is filled. It is a bear to keep bolting and unbolting it to the head hehehe. Expect to burn yourself a couple of times as cast iron holds heat very well. hehehehe.



More small welds, chipping and cleaning between each arc.


After cleaning shaping and dressing with my belt sander.

 

Your in LA

Take it to Kelly's block welding in Santa Monica they are just one of the best in the country take em two or three I think thet have a min charge.

 

In a pinch I have used stainless wire it works to

 

GTSDAVE nothing wrong with that repear

 

never seen cast iron melt, and it wont cut with a torch... sounds like a field trip to the shop to see if i cant slice off a chunk of a cast iron skillet i got layin out there... cause the **** sure as hell melts nice with a henrob torch on O/A

keep in mind, i aint callin ******** here on NO ONE, this is just one of those kinda statements i have to see for myself

 

well now.

seems your all have your **** in order, just not with eachother.

and yea , it melts, but if its not heated put correctly it will crack or shatter
before it melts, preheat , preheat ,preheat, trust me, im a blacksmith,
i should know, id like to see you guys forge weld some of your parts,
it is not easey. Ive had failures and success, but you all must keep in
mind one thing, boredom in the mother of invention.


keep it up guys.