Annealing Copper

[Mellow Mullet]

Trying to stay on budget. I have a lot of extra wire laying around (I used to do electrical work) and have been doing this for a while. It works very well.

 

[edprocoat]

I usuall unwrap it first then straighten it with a snap of two pliers, then I wrap it in a coil about the size of the burner on my stove and turn on the heat. When it glows red I dump it in the sink of water.

ed

 

[Mellow Mullet]

I used to unwrap it too, but have grown lazy. I cut it in two foot lenghts and when finished with the process, store it in a pvc tube. Just uwrap a piece when I need it. It is easier to unwrap and straighten anyway after heating. I do strip it before heating.

 

[bonsaibp]

I would think the unwrapping and seperating could cause it to harden after annealing. Maybe that's not your experience though.

 

[Brian Van Fleet]

I would think the unwrapping and seperating could cause it to harden after annealing. Maybe that's not your experience though.

You're right Bob, technically any movement work-hardens it to some extent. Can't remember if it was Peter or Kathy who was talking about wrapping annealed copper carefully even to simply transport it to a workshop, as the jostling around in the car will work harden it. Although, it's probably slight enough that I doubt I'd notice it.

 

[garywood]

Bob and Brian, don't you just hate hard spots. They always come up, if there are any, right where you need the most control. Above #14 not so bad but the larger the wire, it is proportionaly harder to control.

 

[Mellow Mullet]

The minor amount of movement required to unwind it doesn't have any affect on the softness.
Minor bending or bumping does not either, I think this is one of those myths that gets perpetuated by repetition. Just my experience.

John

 

[crust]

Does anyone anneal in a kiln?

So, does anyone anneal in a kiln? What is you burn schedule or temp routine?

 

[garywood]

So, does anyone anneal in a kiln? What is you burn schedule or temp routine?

Cone 022 gives nice soft wire.

 

[BigDave]

So, does anyone anneal in a kiln? What is you burn schedule or temp routine?

Yes I have for many years. Schedule...for .... wire, go as fast as you want, there is no water steaming/carbon burning etc concerns like ceramics.

I use the bottom switch which controls the bottom two elements, no need to heat the whole kiln. Also saves your arm hair as you reach down to the bottom of the kiln to grab(tongs) the hot stuff...don't ask me how I learned that...

I don't go as high as G-wood, more like 900, a dull red color.

Since there is no cone available at this temp I go by pyrometer... but usually just color, its not that touchy. but if you do forget and get up to the red hots, you will find the finished product somewhat brittle, don't ask me how I know that...

With tongs grab a coil at a time and quench in water, for a cleaner finished wire...

good luck,

-big Dave

 

[Brian Van Fleet]

find the finished product somewhat brittle, don't ask me how I know that

Yeah...I've, uh, read that somewhere too...