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Copper questions


#1

Hi All! I missed you guys! Well, I am out of “lurkdom” for a minute
to, once again, call upon the ultimate wisdom of all you experts
here! (I’m SO grateful for this resource!!!)

I make a few things out of copper wire & piping. First of all, I
have made these purse handles out of 6G copper wire and recently
bought 4 Gage because I thought it to be heavier and probably more
strong for purses of larger size.

Well, I have found that the small coil-like form on the 4G wire
(about 1.5 - 2 inches) I make for the ends is a lot harder to form.
I don’t want to distort the wire any more than I have to. Is there a
way I can make it easier to bend? I am very limited to tools as I
never really have invested too much. My Dad has a vise, hammers,
etc… basic home fix-it stuff… so I can get help from him.

Can I use heat? if so, could I heat the wire with a regular torch
and would it discolor the copper? If it does discolor, is it a nice
color or is it black & yucky? Does it harden after being heated? I
would appreciate any or resources available. I would
also like to put a patina on the copper, but is there a way to do it
so it will not “rub off”? Can the copper be sealed in any way? (to
keep a patina AND/OR to keep it shiny)

I originally liked my first few purse handles I made, but want to
keep experimenting with different ideas and such.

My dad and I also started making wind chimes with the copper piping
and I have a design for the part that the pipes hand from that is a
copper wire form. It needs to be bent into loops and such (about the
same sizes as the purse handles) and I want to apply what I learn to
this project. Same goes for the patinization (is the a word?) and
sealing of the color.

I hope you guys/gals here can help. I appreciate this so much, as
always.

Blessings,
Robin Pittman


#2

Robin,

Try going to an auto parts store like NAPA and ask for a tubing
bender. There is one that uses round mandrels for different size
tubing. It has a handle that bends the tube around the mandrel. This
would probably give you the control you are looking for in the size
you need.

Bill


#3

Hey Robin, Patination is a word :slight_smile: Annealing the copper wire is what
you are looking for in any books you have access to. Basically with
a torch you bring it to a dull red, what a few seconds then put in
water. A hard red crust often forms which you will need to remove.
From many of the Jewellery supplies stores they sell Pickle, a mild
acid, to do this work, you can use it at room temperature, it just
takes much longer. We have a fume hood and a dedicated hotplate for
the pickle (as the fumes are carcinogenic), and we never let it boil
(boiling acid is dangerous). A few minutes in a heated pickle and
then we rinse it, rub gentle with a pumice and a bit of soap (the
soap makes the pumice a little less hard on the hands) for a piece
that we are raising, we like it nice a clean for each course, for
wire work I don’t this is necessary, a little running water and a
little dish detergent and you should be good to go. In the annealed
state your copper will be very malleable and ductile. Last time I
read through Charles’ “Hinges, Clasps, & . . .” book he mentions
that you can age harden metals that have copper in them in a
convection oven (600 degree fahrenheit for 45 minutes-4hours . . .
basically it causes hard copper oxides to form around the molecules
if memory serves which can increase the strength by up to 100%, but
loss of flexibility due to it being a work hardened state). Last
time I did this with copper for 45 minutes I ended up with a warm
orange colouring that I protect with some paste flooring wax that I
worked in by hand, not a perfect solution, but it helps a bit. If
you like the red that you get from heating and quenching during the
annealing stage you can do that and simply not remove it in the
acid, you can then go to the age hardening and see what happens.
Liver of sulphur or another silver blackener will give you a dark to
black patina. Cupric Nitrate (use a fume hood, or out doors, and a
chemical respirator) sprayed or brushed onto a heated surface forms
a blue green patina that is a little fragile. Kitty litter or wood
chips soaked in ammonia then the piece submersed for a few hours to
a few days will create a dark blue patina where the littler/wood
makes contact with the metal (so wet, not a swimming pool with
regards to ammonia, note used kitty litter works better, so if you
or a friend has a indoor cat . . .).

I don’t get your wind chimes question, but bending tubing in general
is a task best taken cautiously, you don’t want to collapse the
tube. Annealing and slowly bending with your hands is most likely
the best solution (unless you see an automotive guy that does body
work and have them do a bunch for ya, or pick up the tube bending
gear they use). What you do to stop the tube from collapsing is the
lightly tap it with a wooden mallet on a wooden base (try not to
mare the metal basically) until it becomes an oval, bend against the
narrowest sides of the oval gently and as it bends the cross section
will become round again, repeat as necessary (SLOW and CAREFUL).

I’m sure others will have good input for ya, too. I just noticed
that Amazon.com has “The Colouring, Bronzing and Patination of
Metals” for 30% off . . . now I’m even more tempted :slight_smile:

David Woolley
Fredericton, New Brunswick, Canada


#4

Yes, you can make the copper more malleable with heat. It’s called
annealing. Check your local library for books on metalsmithing. You
can heat the wire with a propane torch from the hardware store.
Depending on the length of the wire, it may take a while. Lay or
coil the wire on a fireproof surface and put the blue part of the
flame on the metal. Move it along the length constantly. It doesn’t
have to more fast but must move constantly. If you have an electric
stove, you know how red the coils can look. You want the copper to
get very red. It is hard to melt thick copper wire so you don’t have
to worry about melting it. It does not all have to be the same color
at the same time but each section needs to have been that color.
Otherwise, you will have sections that are harder to move than
others. Quench the copper ing water. A lot of the black will flack
off. The rest can be removed with wet and dry sandpaper, steel wool,
scrubbies, and wire brushes. You should then be able to move the
metal with your bare hands. If you need force, try a leather mallet.
If it gets too hard, anneal again and again and again. You are using
a very tight radius for metal this thick. Are you winding it around
something to keep the coils even?

Marilyn Smith


#5

Robin, An episode of “This Old House” showed how to install a
bathroom sink, using bendable copper pipe to supply the water. They
put a special rod inside the pipe to prevent kinking/deforming while
bending it to shape. Then it pulls right out. I guess the curves
can’t be too sharp.

Janet


#6

Filling the pipe/tube with sand can also prevent the collapse when
bending. Mark


#7

When I was an engineering apprentice many years ago a length of
steel spring was inserted into tubing before bending to keep the
tubing open.

Pat


#8

Copper tubing can be purchased from many places. It is also sold in
different forms that must be handled differently. There is soft
copper, frequently used for plumbing, generally sold in rolls that
go up to about 1/2 inch in diameter. This stuff is already annealed
and can be bent in a number of ways. I’ve even gone about it by
slowly wrapping it by hand around a form like a piece of pipe. There
will be limitations on how tight a radius you can obtain this way.
Old timers were also known to plug one end of the tubing, fill it
with fine sand or table salt, plug the other end once full, and then
proceed to bend. This put a filling inside that will easily submit
to forming but that also prevents tube collapse,

Another type of copper pipe sold comes in larger diameters ranging
from 3/8 inch up to semi huge ( I’ve found pieces 4 inches in
diameter but never seen it in stores.) I would recommend plumbing
contractor supply houses. Often this is “hard copper”. It is usually
used for long straight runs of pipe in construction and is soldered
together with “sweat fittings”. This stuff is not annealed and
frequently will break if bent. It has been used for wind chimes and
so on. It can be annealed though, by following the advice already
given in this thread. Once annealed, it too can be formed in a number
of ways. Just remember the tendency of work hardening. If properly
annealed it should be fairly easy to bend. Tubing can be bent by
either inserting an appropriately sized spring into it or
surrounding the copper with a spring. Just make sure that it is a
spring that gives a very close fit to the diameters you use and that
the spring isn’t all stretched out. You are trying to provide
support to the copper.

It’s a slow, occasionally bothersome trick to fill a tube with
tablesalt but I’ve seen it done for bending and it worked very well.
And don’t be afraid to anneal the copper frequently.

Mike


#9
    When I was an engineering apprentice many years ago a length
of steel spring was inserted into tubing before bending to keep the
tubing open. 

Hi Folks…

Conversely, if you hit your local hardware store, there are spring
tubing benders one can buy…the spring goes on the outside of
the tubing in this case… These have a “funnel” on one end to
facilitate the insertion of the tubing, and then you can bend by
hand…shouldn’t cost more than $2-$3…sometimes you can find
them in sets… They come in a number of different sizes (for tubing
1/4" O.D. and up)…

An auto fuel line bender will get you down to 3/16…(that’s the
lever/grooved anvil type)…

Gary W. Bourbonais
AJP(GIA)


#10

You can also put a piece of cable through the tube/pipe and pull the
cable ends and bent the pipe around some object that is the proper
diameter. This works well for large diameter, heavy, steel pipe
when it is needed. The cable is often pulled with a large
catapiller tractor and the pipe is bent around a large tree stump
(not needed here but it sure is interesting to see it done!!!).

John Dach