?? for T-Bone

As T-Bone said, you didn't mention the type or grade but it is generally a good idea to match the weld deposit to the base material if it is known.

309 Stainless steel is recommended for joining dissimilar types of 'austenitic' SS to eachother. When joining austenitic SS to unlike ferrous metals, the 312ss filler material is recommended.

One thing to keep in mind when working with austenitic grades of SS is the fact that it will absorb and also dissipate heat at 1/3rd the rate of carbon steel. Stainless steels also have an oxide layer that makes the SS resistant to corrosion. The heat of welding will destroy that layer. (The layer can be restored by using a pickeling paste.) The heat of welding will also have another detrimental effect on the stainless. The carbon which is present in the base metal chemistry will migrate to the heat affected zone and will combine with the chromium that is also present. This will leave the area outside that HAZ starved of chromium. The metallurgical term for what can occur under these conditions is known as intergranular corrosion. If that is going to be of concern with your project, you should consider getting a pickeling paste at your local gas house.

Thank You and Merry Christmas for our house to yours!

You didn't specifiy what kind of SS so I would go with 309 filler with .045dia. You can also use wire from a wire spool for Mig, scrap metal. 309 is good for all SS welding to dissimular metals, SS to black, etc. as well as SS to SS.

You will want to use a neutral small flame. A small OO size tip or smaller, the smaller the better as it gives much more torch control and weld puddle control. Very clean tip orifice. Better to use too low of heat than too much and you can alaways add more heat if needed. Tack 25 times base metal thickness with a 1/2 base metal thickness root opening. Don't rush it.

Take a piece scrap and use that to see what too much heat does, too little heat, don't tack but every 4" or so and see the warpage you get, try a oxidizing flame, a neutral flame, a reducing flame, move too fast, too slow, etc.

Cost of gas? Are you using too much heat (very common with just learning)? Do you have a leak? Wrong tip size (usually too large of tip)?

Do a search on this website for alot of good welding info. If you can't find something that fits your need, let me know and I'll repost some info or make something up, I mean type something up :).

T_Bone