Annealing Brass

[ptk1126]

I have a large patchbox finial that I need to do a fair amount of tapping and fitting
around the edges.

How many times can you anneal the brass without it becoming brittle or otherwise being affected ?
Because the finial is large I can't heat the entire piece sufficiently and want to do a section at a time.

I don't want to ruin it because I have a lot of time invested in making and engraving it.

Thanks
Paul

[JDK]

I don't believe you can ruin it by annealling too much, only by not annealling it often enough as you work with it.  At least I've never experienced any detrimental effects by annealling often.

For large pieces you don't have to heat the entire piece at the same time to anneal it.  Play the heat on an area to until dull red and then move the torch to the adjacent area and heat until red and so on, each subsequent area will turn pretty quickly as it's already hot.  Continue until the whole part has been done.  Quench or let cool normally and the whole thing will be annealed.

Enjoy, J.D.

[LRB]

  What JDK said, and don't over heat to a bright red, if possible. It will get just as soft air cooling as quenching, but quenching does no harm if your in a hurry.