First, do you know what alloy it is?
Saying "stainless steel" is like saying its a "rock"- is it sandstone, or granite?

304 is the most common alloy of stainless, and is pretty forgiving to forge.
Some other alloys get trickier.

I forge a lot of stainless- get it hot, and when it starts to cool, get it hot again.

mill scale isnt really a problem, so multiple heats, or leaving it a long time in the forge doesnt hurt it much.

Orange-yellow is best. Below dull red, throw it back in.

Stainless takes at least 50% more force to move, even hot, than regular steel- so plan on using bigger hammers, and hitting harder, and getting sore and tired. Power hammers help a lot.

Try to clean off loose mill scale from your anvil, vise, and tooling. Pounded in mill scale will rust. Use clean hammers and tooling. Use brand new stainless steel wire brushes, brand new sanding discs and grinding wheels, and dont grind mild steel and let the sparks land on your stainless, hot or cold.

After forging, heat to orange, and immediately quench in cold water- this will help it stay "stainless".

Wire brush, sand or grind it as desired- but never use an abrasive that has previously been used on mild steel.

Andy,

Ries pretty much said all there is to know about forging stainless steel. I'll add that there is also an alloy of stainless known as 304L, the "L" suffix indicating "low carbon", and it is a bit easier to forge ( a very little bit), and it is easier to keep it stainless through the solution annealing that Ries described.

If you want your finished work shiny and bright, you'll find that polishing stainless is no fun. It is abrasion resistant. I recommend that you do what Ries does - send it out for electropolishing.

Another fairly common alloy of stainless is 316, largely used for marine stuff. It can be forged, too. Again, not that easy but do-able.

Give it a go and have fun!

Rich

You have a really helpfull electropolisher near you in Aldershot called Electropol Poligrat ... they can just clean or clean and polish ....depending on the finish you want.
A soaked heat is better than a sudden one ...direct flame is not kind either.
Try to avoid long bars sitting half out of the oven for too long ... you will get patchiness when polished.
A good source of offcuts of 304L is Aalco in Southampton

Giusseppe

Where to bend next ... www.metalgarden.ca