I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

On Wednesday, November 14, 2012 1:45:03 PM UTC, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)

to make a toy boat along this line:



https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG



I tried some 10 mm (or so) pipe that I found in the cellar, and it

kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby

shop (aimed at model railways, I think), and that's even harder to

bend & easier to kink.



Is it worth trying to anneal a piece with a blowtorch? If so, what's

the best procedure?

I just bropught some of this for a studetn project.

http://www.tradingdepot.co.uk/DEF/pr...10mm%20x%2010m

similar thing in be here & queue

http://www.diy.com/nav/fix/plumbing/...-x-10m-9264631

no ideas if it's suitable ....

"whisky-dave" wrote in message
...
On Wednesday, November 14, 2012 1:45:03 PM UTC, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)

to make a toy boat along this line:



https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG



I tried some 10 mm (or so) pipe that I found in the cellar, and it

kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby

shop (aimed at model railways, I think), and that's even harder to

bend & easier to kink.



Is it worth trying to aneal a piece with a blowtorch? If so, what's

the best procedure?





I just bropught some of this for a studetn project.

http://www.tradingdepot.co.uk/DEF/pr...10mm%20x%2010m

similar thing in be here & queue

http://www.diy.com/nav/fix/plumbing/...-x-10m-9264631

no ideas if it's suitable ....

Fill with fine dry sand, seal the ends and bend.
The sand "should" stop the walls of the tube collapsing.

On 14/11/2012 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?


Heat to cherry red, then plunge into cold water.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Colin Bignell

On 14/11/2012 14:22, Nightjar wrote:
On 14/11/2012 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?


Heat to cherry red, then plunge into cold water.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Colin Bignell

Woods Metal not cheap

http://www.ebay.co.uk/sch/i.html?_od...end&_sacat =0

For this relatively small application you could always use plumbers' solder.

"Adam Funk" wrote in message
...
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Copper is very easy to anneal. Heat until the copper is a uniform dull red
colour and then either quench in water or just leave to cool. Keep moving
the flame around so as not to overheat or burn any particular area. A dimly
lit room makes the colour easier to see. Unlike ferrous metals which harden
with a fast quench and anneal with a slow cool, copper also anneals with a
fast quench. Because copper work hardens so quickly if you bend or hammer it
you may need to anneal it multiple times as you work it into the desired
shape but you can do so as often as you like without harming the material.
--
Dave Baker

On Nov 14, 1:45*pm, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. *I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? *If so, what's
the best procedure?

Most of the copper pipe you buy is in hard or "half hard " condition.
Makes it stronger.
You can anneal it by heating to red heat and letting cool.
It will then bend better but will have reduced pressure rating.

Annealed pipe can be bought, it usually comes in a coil and is thicker
guage hence more expensive.

One thing you might do if it is a project is consider automotive
hydraulic copper brake pipe if you need a really high pressure.

On Nov 14, 1:45*pm, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. *I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? *If so, what's
the best procedure?

To stop it from kinking, you can buy and external spring,fits over the
pipe while you bend it.

On 14/11/2012 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Get it glowing cherry red green tinge to flame and then drop it in a
bucket of water. Fine pipe may throw a jet of hot water out so wear eye
protection. Dry sand in the tube and ends sealed with wax or tape before
you try to bend it will make it keep its shape.

You only need to anneal the part you will be bending.

--
Regards,
Martin Brown

harry wrote:

One thing you might do if it is a project is consider automotive
hydraulic copper brake pipe if you need a really high pressure.

For a pop pop boat? I think that might be overkill. ;-)

Tim

On 14/11/2012 14:53, newshound wrote:
On 14/11/2012 14:22, Nightjar wrote:
On 14/11/2012 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?


Heat to cherry red, then plunge into cold water.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Colin Bignell

Woods Metal not cheap

http://www.ebay.co.uk/sch/i.html?_od...end&_sacat =0


But it lasts forever. I inherited mine from my father.

For this relatively small application you could always use plumbers'
solder.

That would leave a residue inside the tube, which Wood's metal usually
does not. As the application seems to involve heating the coil, that may
be important.

Colin Bignell

On 14/11/2012 16:20, Nightjar wrote:
On 14/11/2012 14:53, newshound wrote:
On 14/11/2012 14:22, Nightjar wrote:
On 14/11/2012 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?


Heat to cherry red, then plunge into cold water.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Colin Bignell

Woods Metal not cheap

http://www.ebay.co.uk/sch/i.html?_od...end&_sacat =0



But it lasts forever. I inherited mine from my father.

For this relatively small application you could always use plumbers'
solder.

That would leave a residue inside the tube, which Wood's metal usually
does not. As the application seems to involve heating the coil, that may
be important.

Colin Bignell

In principle, but would it be likely to matter for this low-tech
application? In my experience, without flux the solder just won't wet
the oxidised bore.

I think annealing might be enough with thick-wall tube, but I'd be
nervous about modern tube kinking without internal support. The sand
method is good, but is it easily removed from a relatively tight set of
coils?

--
For every complex problem, there is a solution which is simple, neat,
and wrong.
H L Menken

On 2012-11-14, newshound wrote:

On 14/11/2012 14:22, Nightjar wrote:

Heat to cherry red, then plunge into cold water.

I'll try it.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Woods Metal not cheap

Let me put it this way: I spent less than £2 on the hull *and* I got
to eat the kippers.

On 2012-11-14, Tim+ wrote:

harry wrote:

One thing you might do if it is a project is consider automotive
hydraulic copper brake pipe if you need a really high pressure.

For a pop pop boat? I think that might be overkill. ;-)

To be powered by a candle or alcohol lamp, so as someone else has
said, this is a low-tech application.

On Wed, 14 Nov 2012 13:42:37 +0000, Adam Funk
wrote:

I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Nice project method, including the bending.

http://www.nmia.com/~vrbass/pop-pop/buildpop.htm

Never seen it before but I may spend a few hours next year making one.

Thanks for dragging it in.

On 14/11/12 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Try copper brake pipe.

On 14/11/2012 20:20, Adam Funk wrote:
On 2012-11-14, newshound wrote:

On 14/11/2012 14:22, Nightjar wrote:

Heat to cherry red, then plunge into cold water.

I'll try it.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Woods Metal not cheap

Let me put it this way: I spent less than £2 on the hull *and* I got
to eat the kippers.

OK but £13 for a kilo of Woods metal when you need less than 100 grams.
An engineer is someone who can do for a shilling what any fool can do
for a pound.

On 14/11/2012 22:59, newshound wrote:
On 14/11/2012 20:20, Adam Funk wrote:
On 2012-11-14, newshound wrote:

On 14/11/2012 14:22, Nightjar wrote:

Heat to cherry red, then plunge into cold water.

I'll try it.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Woods Metal not cheap

Let me put it this way: I spent less than £2 on the hull *and* I got
to eat the kippers.

OK but £13 for a kilo of Woods metal when you need less than 100 grams.
An engineer is someone who can do for a shilling what any fool can do
for a pound.

The cadmium puts me off a bit...

--
Rod

On 14/11/2012 22:07, Chris Bartram wrote:
On 14/11/12 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Try copper brake pipe.

Normal brake pipe is plated steel, top quality brake pipe is a copper
nickel alloy of some sort. Both of these have lower thermal conductivity
than copper, and will be significantly thicker than you need for your
working pressures.

On 14/11/2012 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

I used 3mm OD pipe (or thereabouts) and wrapped it around a bit of dowel
to get the coil. No woods metal, no sand, no solder, nothing.

The former helps a lot.

Andy

On Wed, 14 Nov 2012 23:02:10 +0000, newshound wrote:

On 14/11/2012 22:07, Chris Bartram wrote:
On 14/11/12 13:42, Adam Funk wrote:
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Try copper brake pipe.

Normal brake pipe is plated steel, top quality brake pipe is a copper
nickel alloy of some sort. Both of these have lower thermal conductivity
than copper, and will be significantly thicker than you need for your
working pressures.

I remember that stuff. Many years ago I had a 1952 Land Rover, and had to
replace some brake pipes. The dealer sold me a steel one, right length
but not bent to shape. I found it impossible to do a 3-D bend in it,
under the floor, without kinking it. In the end I managed to buy the
copper alloy stuff, get the unions, flares etc. put on, and found that
much better. But more expensive!



--
Use the BIG mirror service in the UK:
http://www.mirrorservice.org

*lightning protection* - a w_tom conductor

On 14/11/2012 23:01, polygonum wrote:
On 14/11/2012 22:59, newshound wrote:
On 14/11/2012 20:20, Adam Funk wrote:
On 2012-11-14, newshound wrote:

On 14/11/2012 14:22, Nightjar wrote:

Heat to cherry red, then plunge into cold water.

I'll try it.

To be sure, fill the annealed tube with Wood's Metal, bend to shape,
then melt the Wood's Metal out by placing the tube in boiling water.

Woods Metal not cheap

Let me put it this way: I spent less than £2 on the hull *and* I got
to eat the kippers.

OK but £13 for a kilo of Woods metal when you need less than 100 grams.
An engineer is someone who can do for a shilling what any fool can do
for a pound.

The cadmium puts me off a bit...


Just wear an old asbestos face mask....

"Dave Baker" writes:

"Adam Funk" wrote in message
...
I'm trying to curl up some small copper pipe (or tube, if you prefer)
to make a toy boat along this line:

https://en.wikipedia.org/wiki/File:R...pe_pop_pop.JPG

I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I got some "5 mm X 0.45 mm" tubes from a hobby
shop (aimed at model railways, I think), and that's even harder to
bend & easier to kink.

Is it worth trying to anneal a piece with a blowtorch? If so, what's
the best procedure?

Copper is very easy to anneal. Heat until the copper is a uniform dull red
colour and then either quench in water or just leave to cool. Keep moving
the flame around so as not to overheat or burn any particular area. A dimly
lit room makes the colour easier to see. Unlike ferrous metals which harden
with a fast quench and anneal with a slow cool, copper also anneals with a
fast quench.

How does that work? As I understand it, annealing happens while
the metal is hot: the domains grow. A fast quench (of metals
that go this way) causes rapid contraction which puts
unconformities into the domains as they cool, so hardening
(outer) parts. I suppose in copper this doesnt happen as much
for some reason?

--
Jón Fairbairn
http://www.chaos.org.uk/~jf/Stuff-I-dont-want.html (updated 2012-10-07)

On Wednesday, November 14, 2012 1:45:03 PM UTC, Adam Funk wrote:
I tried some 10 mm (or so) pipe that I found in the cellar, and it
kinked too easily. I

You can get a pipe bending tool for 10mm copper pipe. Works nicely.

Robert

On Thursday, November 15, 2012 10:50:15 AM UTC, Jon Fairbairn wrote:
"Dave Baker" writes:
Unlike ferrous metals which harden with a fast quench and
anneal with a slow cool, copper also anneals with a
fast quench.

How does that work? As I understand it, annealing happens while
the metal is hot: the domains grow. A fast quench (of metals
that go this way) causes rapid contraction which puts
unconformities into the domains as they cool, so hardening
(outer) parts. I suppose in copper this doesn’t happen as much
for some reason?

Oh god. [/me tries to recall Metallurgy from when we were both
at Cambridge].

In both copper and ferrous metals, heating a work-hardened piece
allows the dislocations to move around, untangle themselves, and
dissipate. This removes the work hardening.

When you heat ferrous metals, they undergo a phase change to a
different crystalline form (which happens to be hard). If you
then cool them fast, they don't have time to change crystal
layout, so they stay hard. If you cool them slowly, they /do/
have time to change crystal form, so end up soft.

Copper doesn't undergo this phase change, so can be annealed
quickly.

Martin Bonner writes:

On Thursday, November 15, 2012 10:50:15 AM UTC, Jon Fairbairn wrote:
"Dave Baker" writes:
Unlike ferrous metals which harden with a fast quench and
anneal with a slow cool, copper also anneals with a
fast quench.

How does that work? As I understand it, annealing happens while
the metal is hot: the domains grow. A fast quench (of metals
that go this way) causes rapid contraction which puts
unconformities into the domains as they cool, so hardening
(outer) parts. I suppose in copper this doesnt happen as much
for some reason?

Oh god. [/me tries to recall Metallurgy from when we were both
at Cambridge].

In both copper and ferrous metals, heating a work-hardened piece
allows the dislocations to move around, untangle themselves, and
dissipate. This removes the work hardening.

Thats essentially what I thought, but probably a more accurate
description than my memory of it (I didnt do much metallurgy,
switching to compsci).

When you heat ferrous metals, they undergo a phase change to a
different crystalline form (which happens to be hard). If you
then cool them fast, they don't have time to change crystal
layout, so they stay hard. If you cool them slowly, they /do/
have time to change crystal form, so end up soft.

Copper doesn't undergo this phase change, so can be annealed
quickly.

Thanks. That makes sense.

--
Jón Fairbairn
http://www.chaos.org.uk/~jf/Stuff-I-dont-want.html (updated 2012-10-07)

On 16/11/2012 11:11, Jon Fairbairn wrote:
Martin Bonner writes:

On Thursday, November 15, 2012 10:50:15 AM UTC, Jon Fairbairn wrote:
"Dave Baker" writes:
Unlike ferrous metals which harden with a fast quench and
anneal with a slow cool, copper also anneals with a
fast quench.

How does that work? As I understand it, annealing happens while
the metal is hot: the domains grow. A fast quench (of metals
that go this way) causes rapid contraction which puts
unconformities into the domains as they cool, so hardening
(outer) parts. I suppose in copper this doesnt happen as much
for some reason?

Oh god. [/me tries to recall Metallurgy from when we were both
at Cambridge].

In both copper and ferrous metals, heating a work-hardened piece
allows the dislocations to move around, untangle themselves, and
dissipate. This removes the work hardening.

Thats essentially what I thought, but probably a more accurate
description than my memory of it (I didnt do much metallurgy,
switching to compsci).

When you heat ferrous metals, they undergo a phase change to a
different crystalline form (which happens to be hard). If you
then cool them fast, they don't have time to change crystal
layout, so they stay hard. If you cool them slowly, they /do/
have time to change crystal form, so end up soft.

Copper doesn't undergo this phase change, so can be annealed
quickly.

Thanks. That makes sense.


The copper bit is OK, with iron and steel it is all a bit more
complicated and depends on the carbon level. Plenty of stuff on the web!