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Robson Valley
4th February 2012, 06:14 AM
I have intentions of hammering out some bird beaks (for wood carvings) from 6mm copper rod. Probably some grinding/filing sanding also.
I know that the metal "work-hardens" and that I can heat it up with a torch to return it to a softer state for more hammer work. I don't care how often this needs to be done.

Question: After heating, do I quench the piece in water or not? Can't remember.
Question: will the same procedure work for 9mm aluminium rod?

Thanks

Old-Biker-UK
4th February 2012, 07:10 AM
To anneal copper get it red hot, you can quench or not, makes no difference. You sort of get to know when it needs annealing.
Aluminium (and alloys) are a bit more tricky to anneal (a lot depends on the alloy)
Heat it up and before it gets red hot you will have a pool of metal on the bench...
If you don't know the spec. then a reasonable 'home shop' method for annealing is to rub the metal with a bit of household soap, heat up till the soap goes black then air cool. I've used this method a few times & seems to work OK, last job was to hammer an old ally saucepan into a half sphere for an engraving pitch pot.
Mark

Claw Hama
4th February 2012, 07:56 AM
With Aluminium the slower it cools the better, if it cools quickly it will crystalise and then fracture when you hit it. Same when welding. You can even wrap it in some insulation to slow the cooling.

Robson Valley
5th February 2012, 12:35 PM
Terrific. Thank you. I have some fairly large pieces of 2cm slate for a bench top.
I guess I'll just start and play with the first pieces! I am really keen to work with the copper = the color will go so well with the wood carvings in western red cedar.

Old Biker: thanks for the soap trick. I have no idea what's in the aluminium rod that I bought.
Claw Hamma: I can make a pillow of glass fiber insulation to push the hot rod into.

I'm still on the road, back home Monday if the WX doesn't turn nasty with a winter blizzard. That can turn 2+ hrs on a mountain highway into 6 hrs or worse so I could get stopped right where I am.

Claw Hama
5th February 2012, 05:05 PM
Yes copper and Western Red will look great. I did a dining table a few years ago that had 14 Australian timbers in it divided by copper strips. Came up very big:U.

Robson Valley
6th February 2012, 10:40 AM
Very nice table and an encouraging palette of colors. Thanks for posting an example of how nice it can look. Sometimes, WRC has color bands/stripes in it, we call it rainbow cedar. I want to make the hummingbird bodies from that.
I split some WRC a couple of yrs ago, part of it was absolutely copper pink.. . . . . but it faded and yellowed over the next few months. No idea why there's the two sorts, can't usually see until I split the log (the ends and often bleached/weathered or just plain dirty.)

Claw Hama
6th February 2012, 08:54 PM
Sounds like it will be great, can't wait to see it.

bsrlee
8th February 2012, 01:27 AM
You heat & quench copper and copper based alloys to soften them, letting them cool in the air will make them brittle and hard-ish ( they will crack or snap before you can do anything useful with them)

Basically it is the opposite of iron based materials where you heat to red & quench to harden & slow cool to soften, which is why iron was considered to have 'magical' properties in some early cultures, as it was the opposite of the then common & well known copper based metals.

Aluminium is just a right pain.........

Robson Valley
8th February 2012, 03:51 AM
Here's some rainbow cedar. The banding shows only on the radial and transverse faces.
On the left side are some pieces of the ordinary western red cedar = white sapwood and brownish-red heartwood. The sapwood can develop rotten/punky spots so it's common to strip that off the entire log as a first step. The ruler is 6"/15cm.
I have a big owl mask WIP but I carved into the surface, the tangential face and nothing shows until you look at the work from the side. Most disappointing.

RayG
8th February 2012, 01:02 PM
You heat & quench copper and copper based alloys to soften them, letting them cool in the air will make them brittle and hard-ish ( they will crack or snap before you can do anything useful with them)



Hi brslee,

Not quite correct, most copper alloys it doesn't matter how fast or slow you cool, there is an exception for a small group of alloys that can be precipitation hardened, but that;s a whole other story..

The way to harden copper is work hardening. Pound away at it with a hammer. :)

Heating and then air cooling is fine, it won't make the copper brittle or hard.

Regards
Ray

Claw Hama
8th February 2012, 02:39 PM
Yep, what Ray said.