best way to weld cast iron

[DPSwelder]

Hey guys I was wondering what the best way to weld cast iron is I normally just braze it.

[cruizer]

preheat, weld with ni-rod, and a slow post heat. kitty litter, or floor dry around the part works well to retain the heat

[eecervantes83]

I use fiberglass blankets and bricks. 55 nickle rod works well

[walker]

I have used plenty of nickel rod and it works good. I have also used the Crown Alloys 44-30 MIG wire for cast iron with good success. It is expensive, but is an easy solution for most cast repairs. I have not had great luck with either on cast iron exhaust manifolds, as they seem to get burned out over time, and don't like to weld well.

[gnforge]

best way to weld cast iron

Also plain fiberglass the old pink stuff you put between studs. Pull off the paper backing and wrap.
Very cheap, works great, no mess.
I will sometimes wrap part in fiberglass then wrap in welding blanket. Stays hot for a long time and saves your blanket when part is very hot. Also use this when welding 4130 alloy parts for slow cooling.

[H80N]

I don't do a lot of cast iron these days... but when I do...

I have had pretty good luck with
Cronatron™ 211 Cast Iron MIG Welding Wire

using 98-2 Argon/Oxy gas

http://www.lawsonproducts.com/Cronatron/211-Cast-Iron-MIG-Welding-Wire/CW2058.lp#documents

[walker]

WOW at $132 per pound, I hope you would have good luck with it.

[old jupiter]

When I can (smaller parts), and have a good idea what kind of iron it is, AND have cleaned it as best I can (hot vapor degreasing is good if you know a place that does it), I vee out the crack with a rotary file (grinding is said to smear the carbon). I get it heat-soaked up to the desired temperature, with firebrick and asbestos cloth around it to keep it at the right heat, then gas-weld it with cast iron rod, and very slowly cool it. Use cast iron flux; feed the rod into the mushy puddle with a sort of jabbing action that tends to shove the impurities out of the puddle. Kind of a fun change of pace thing to do, and seems to work out well.

I hear there's a guy around here that repair-welds cast iron cylinder heads by gas-welding. Some time I'd like to go watch him work (just out of curiousity. not as anything I'd want to do regularly) . . . .

[aametalmaster]

Depends what the part is. Not really any wrong answers...Bob

[elvis]

I know it isn't welding cast iron, but do any of you guys tig braze it with silicone bronze?

[Hardrock40]

I know it isn't welding cast iron, but do any of you guys tig braze it with silicone bronze?

I think silicone bronze with tig is the cats meow. I have used it on an old, I do mean old wood stove door to replace a broken out section and a hinge.

Old cast iron bed frame and several other odd and hard to repair projects.

An engine block or cast manifold I have never tried it on those, but I would.

IMO its quick and easy.