I need to modify a round AL drain pan as used under a hot water tank for my rent house (code requirement). Due to space limitations (the entire house is only 600 sq ft), I need something that is oval shaped
- I am unable to move either the chimney or the furnace to gain more space for a larger dia. pan. My local sheet metal place can make a square one out of steel but because of a serious lack of room that will not clear the hot and cold supply lines. If I could find a round one in steel I could easily cut, bend and braze it. I have looking in Grainger and McMaster-Carr. As reference, a typical steel automotive oil drain pan is 16 inches in dia.
What I have found is an aluminum pan intended for use as a hot water tank drain pan, about 3.5 inches deep, that is 20 inches in dia. at the base and flairng out to about 21 inches in dia. at the lip. I need to make it have two flats, such that the width across the flats is 19.3 inches.
After I do the relief cuts, would there be any benifit in trying to anneal it prior to trying to rework the part? I do not know anything about the alloy used - I assume that it is something like 3003 (strictly a guess based on reading the various alloy descriptions in my metals catalog). The aluminum mics 0.031 thick. For annealing, all I have available is either a brazing or cutting torch. I have used the cutting torch with an acetaline rich flame to heat and soften similiar thickness steel that I was hammering to shape.
Then I still need to resolve how I am going to rejoin the cut pcs. I no longer have access to a TIG. I could give it to a welder - I hate to outsource something that is tangentially hobby related. I could buy the super duper $100 special lenses and try to gas weld it but I wonder if I would need a mini torch - I have an old Victor J100 w/ a000 tip. Ideas/suggestions?