AusBonsai

Mitchell wrote:

Scott Roxburgh wrote:I use aluminium for deciduous trees and 'home annealed copper' for the few shimpaku and pines that I have.

Oh come on!! " 'home annealed copper' " and your not going to elaborate??.?? I insist on a topic! Or at least a brief explanation....!!

Annealing is quite easy if you have the equipment like a bunsen burner or blow torch. Heat the metal until it glows red, then let it cool. It reduces the grain boundaries making shaping easier, yet retains its strength. The trick will be to anneal wire on a roll. Not sure how easy that would be! Scott would have to elaborate on that!

Glenda
!

Mitchell wrote:

Scott Roxburgh wrote:I use aluminium for deciduous trees and 'home annealed copper' for the few shimpaku and pines that I have.

Oh come on!! " 'home annealed copper' " and your not going to elaborate??.?? I insist on a topic! Or at least a brief explanation....!!

Ok first some links for basic info:
Brent from Evergreen Gardenworks -
http://www.evergreengardenworks.com/copperwi2.htm
http://www.evergreengardenworks.com/copperwi.htm

Jim Gremel -
http://www.jimgremel.com/moreaboutcopper2.html

The process is pretty simple:

First the hardest part of the whole process, getting varying sizes of electrician's copper wire, used in house wiring, mine has been 'offcuts' of about 1-2 metres long for free!!!;
Strip off the plastic;
Roll it up in a loose coil about 30cm in diameter; < This large diameter coil makes it easier to not bend the wire, hardening it, prior to putting it on the tree.
Crank up the BBQ, or wood heater; <don't do it inside your house though
Heat the wire until it is red hot; and <do not put this down on anything flammable as there will be a huge fire!
Put the red hot wire into a drum of water to cool.
After annealing, try not to bang the wire against anything or drop it, as this will work harden it again.

There we have annealed copper wire. Ok, this process does not give perfect hard-spot-free wire! I have used some of Jim's in the States and it was sooo much softer (as soft as aluminium), and easier to use than my own, I guess that takes years of practice to get right.

I also want to say that this wire can be a pain to use because the lengths are subject what you can find and the hard spots can be annoying. If you can find a source of long lengths of copper wire cheaply, buy it and give it a go.

Im sure i've missed something but i'll try to document the process after Christmas when I do some more and take some pics.

Scott Roxburgh wrote: Heat the wire until it is red hot; and <do not put this down on anything flammable as there will be a huge fire!
Put the red hot wire into a drum of water to cool.
After annealing, try not to bang the wire against anything or drop it, as this will work harden it again.

There we have annealed copper wire. Ok, this process does not give perfect hard-spot-free wire! I have used some of Jim's in the States and it was sooo much softer (as soft as aluminium), and easier to use than my own, I guess that takes years of practice to get right.

This is actually called quenching because you are putting it in water. Fine for copper, but will make aluminium brittle. Aluminium should be annealed, which means leaving it to cool naturally after heating.

Glenda

You can let it cool naturally if you want but copper won't go brittle unless you cool extremely fast, water won't do it. My

I use water so nothing catches on fire
Also, using water reduces the metals oxidisation time too...have a read of the links that I put up, they are great at explaining the process particluarly Brent's articles.

You guys seem to be talking at cross purposes a bit. Annealing copper and aluminium has already been discussed on a previous topic.

My trade is as a Fitter/1st Class Machinist, and in particular during my apprenticeship in the '60's' I was lucky enough to do a fair bit of annealing - in particular on Copper and Steel.

Basically, annealing is to return the wire to a soft condition, whether it be copper, aluminium or steel. To soften Aluminium it is heated up to the required temperature and allowed to cool down naturally. Copper is heated up to the required temperature and quenched quickly. Steel is heated up to 'cherry red' and allowed to cool naturally (it was even put in the embers of a fire to cool very slowly). It was annealed to allow it to be worked with a hammer etc on an anvil. To temper the steel again to the correct degree of hardness, it was again re-heated to cherry red and quenched rapidly. That hardened it again. We used an oil bath - water was too 'vicious' and could cause cracks in the hardened material. It was then re-heated to whatever temperature was required for the application. We didn't have pyrometers, we went by the colours that rise from where it was heated. Straw coloured was suitable for centre punches, cold chisels etc (fitters, machinists, boilermakers and welders will know what I'm referring to here). Dark blue was for spring steel. This was on high carbon steel, not the ordinary mild steel which is a general purpose steel and can't be hardened very much.

By the way, copper not only 'work hardens' as you bend or work it, it also 'age hardens' in the passage of time.

That's my for what it's worth.

I'm sorry if this is posted elsewhere, but I thought this thread seemed most appropriate for my query.


I was wondering if there is anywhere locally (Australia) to buy small quantities 100-500g of copper wire around 1.5 - 2mm diameter?

I noticed Scott mentioned using electrician's wire which he strips the plastic coating off. The only wire I have seen like this is actually lots of fine strands that make up one wire within the plastic sheath. Is there another type that is one "strand" inside the plastic sheath??

Cheers

You can separate the the multi-strand wire and use this...

there is electrician cabling that has 3 core wires(sheathed)red/black/green and cabling that has 2 core wires(sheathed)green and brown or black i think,
The 3 core cabling usually has the thinner multi strand wires ,
The 2 core cabling usually has a single wire inside the inner sheath. It is thicker and slightly harder to use. You could anneal it but i like to use it as is.

Thanks Scott and Craig

I am guessing electrician's wire would be cheaper to buy anyway