Soundguy said:
I am thinking I was involved in that thread but as far as welding that part I would price a new one and then decide if it was worth trying to weld it.The first thing in welding is to determine which material it is,either cast iron or cast steel.A spark test is usually quite accurate for this.At work we have a machine that will give you the exact chemical analysis of any metal but most people don't have access to this.If the sparks are cherry red it is usually cast iron,if orange then cast steel.As far as how I would weld it the process is very similar,just a bit more care is required with cast iron.First the part would have to be meticulously cleaned.Next I would put a few very small tacks,just enough to hold the pieces together.Then preheat with a torch but not very much,maybe 150 F.The process I use at work would be TIG welding with a Certanium 423T rod.Obviously the joint will have to be bevelled and welded intermittantly from side to side.Depending on the heat input and how long it takes to weld it,I may play the torch over it to keep the heat input uniform.After welding is complete I would run the torch over the part to spread the heat out uniformly and wrap it in a piece of fire retardant cloth and let cool over night.I should add that if I didn't think the weld was going properly I would have stopped at that point and realized it would not be a sound weld.There are various ways to weld cast pieces but this is a method that has worked for me.Experience will let me decide if I think the welded part should be put in service or not,it is a judgement call.I will say it will be hard to get 100 percent penetration in the joint without getting burnthrough to the inside so this will compromise the welded area somewhat.Probably not as easy as it may look at first,I guess the cost of a new part would have a lot to do with the decision of repair or replace.After writing this I took another look at the photo. Hard to tell but it looks like it would be hard to get at one side of the joint because of the way it is made.The weld would have to go from the sides inward,not top to bottom if I am making myself clear.Because of the shape of the part it may be hard to get a grinder or torch at that side without doing damage outside the weld area.As I said things are never as easy as they may appear.
