cast iron welding

Oh, good. Welding cast iron is an acquired skill.

Howdy,

Welcome to CR4. Can you give some more information please? Do you want information or do you want to tell us something?

Most would assume you reference to cylinder head mating surface? Or oil gallery? Or Rear webbing? Or???

What type repair? A crack? A steam cut? From water jacket to cylinder wall? Between cylinders?

Try to be very simple in explanation.

Thanks

Hello hyitim,

You said "I HAVE some information..."

Please share it with us. (or did you mean "NEED" as TVP45 alluded to?

I have seen cast iron blocks braze welded and metal stitched.

The advantage of metal stitching is that no heat is applied, therefore no warping or stress related problems.

If you want to weld the block WIA CIG etc have a specialised welding rods for the purpose. When welding cast you should uniformly heat the block first and then slowly cool the block when finished or you will get further cracking on cooling we use an old oven to pre heat and cool the cast we weld.

I agree with Grochy. You should preheat and post heat the cast. Ovens are great for this as they do not introduce carbon soot to the surface to be welded as an acetylene torch with a rose bud tip could. I would use nickle rods for the repair if it is near a cylinder wall or other high stress area. But, if the weld is for low stress areas such as repairing a mounting surface for a water pump, I would probably use brazing. If you are repairing a crack drill a small hole at each end of the crack to prevent it from spreading. The holes are drilled prior to welding. More information is needed so we can better help you. How big is the engine? Could it fit in an oven? What is the defect that needs repaired? Or, as stated before in a previous post, are you wanting to pass information to us???

Even if you preheat the piece, if you use nickel rod you should weld in short stitches and peen the weld material immediately. Reason? The cooling rates of cast iron and the nickel rod are different and the weld material will shrink away from the cast iron as it cools. If it is indeed a cracked block you might check with Lincoln Electric. They, at one time, had a rod especially for this purpose. I heard great things about it.

If it is a broken section such as a maching part you may well be better off brazing it. Build the brass up above and well out horizontally from the break if possible. Either way to get any strength at all a break you must v it out down to the point you just leave "witness marks" to line it up.

In preheating for brazing most people don't heat it up enough. We often say that by the time the job is finished the heat is up to where it should have been to start.