Thread: Question on welding cast iron.

Thankyou for the pics Mark and Rick. They look clearer than when they first appeared in the magazine. Coincidently a bloke on pirate from the US asked me the other day if I had pics of the old girl, but the ones I had plus the vehicle and most everything else went up in the bush fires a couple of years back. At least now I can give him a link to this thread.
Wagoo.

Wagoo I welded alot of cast iron and found cast iron rods put too much porosity into the weld.I used to get the part hot over a furnace then weld it with J200 stainless steel rods and again put it on heat and let what I was welding cool slowly overnight keeping it on the heat all the way.Cast will crack within minutes if it's not hot or let to cool too quickly.Personally I would do it as a last resort. Pat

Originally Posted by wagoo

Thankyou for the pics Mark and Rick. They look clearer than when they first appeared in the magazine. Coincidently a bloke on pirate from the US asked me the other day if I had pics of the old girl, but the ones I had plus the vehicle and most everything else went up in the bush fires a couple of years back. At least now I can give him a link to this thread.
Wagoo.

Or better still, right click on each picture, then click "save image as" or "save target as", then save them on your computer. Then create a photobucket account and upload them there for safekeeping (and forums).

Originally Posted by isuzurover

Never heard of nodular cast iron?

Sure, great stuff if you making sewer pipes or galv water/ air fittings. in which case just glue them together with a GP

OPS, and ductile shows up as silver not dark gray

Years ago, and then did not do a lot, but used either the cast iron rods or stainless steel. Only did very short runs with a lot of peening to take the stress out of the weld. Helps to have someone with the hammer at the ready as soon as you put down the arc. You may be lucky but I would expect it to fail.

There is a bloke over on 4wd action forum that is mating a Navara cab onto an F250 chassis. He is a welder or fabricator of some sort, he gusseted his diff housing. He used a big wok/bbq burner to heat up the diff before welding

Pre-heated with this ring burner. It got it to over 250 degrees and then I used the heating tip on the oxy to get it dull red hot before welding the cast iron sections. Seems to have worked well. No cracks or fractures at all so I'm happy.

Any uneven rapid heating and cooling will cause distortion.
Not such a problem for smaller section materials because the welding will heat it up right through. It may distort but usually won't affect the integrity of the weld. But welding thick materials and especially cast iron the welding won't heat right through so when it cools and contracts the weld may simply pull away from the parent metal. Especially with cast iron because it is so ridgid it doesn't like to move or distort. By thoroughly pre-heating it, the temperature changes that occur when it is welded is greatly reduced and the cast iron will tolerate welding. There is many variations of cast iron too. Some are virtually impossible to weld, some not so bad. Fortunately these diff housings are pretty good when pre-heated like I did.

That damned bug ....got me AGAIN! ........