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| gearhead... |
 Posted: Fri Jul 03, 2009 4:22 pm |
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Guest
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I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
Just getting it wet and letting it sit will take much too long. I
need a way to speed up the reaction. I've thought of putting the
steel in water and applying a voltage to it like electrolytic
cleaning, but backwards. I've read that electrolytic rust removal
involves applying a negative voltage to the workpiece and placing a
positive sacrificial electrode in the solution. So presumably I could
reverse the polarity and apply positive voltage to the workpiece if I
want it to rust. But from what I've read about electrolytic cleaning,
the positive electrode actually dissolves -- and I don't want that.
Perhaps if I use plain water instead of an electrolyte, the positive
electrode would not dissolve. Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this? |
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| dangerousbill at (no spam) gmail.com... |
| Posted: Fri Jul 03, 2009 4:57 pm |
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Guest
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On Jul 3, 7:22 pm, gearhead <nos... at (no spam) billburg.com> wrote:
[quote:b1858d6b3f]...Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?
[/quote:b1858d6b3f]
Soft iron will rust pretty quickly under the right conditions. Put it
in a Ziplok plastic bag, with a few tablespoons of water, and put it
in a warm place overnight. Washing with paint thinner, soap and clean
water will remove any grease that will slow the process.
If you can use hydrogen peroxide instead of water, the rusting will
probably go much faster.
Dangerous Bill |
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| gearhead... |
| Posted: Fri Jul 03, 2009 5:21 pm |
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On Jul 3, 10:57 pm, "dangerousb... at (no spam) gmail.com"
<dangerousb... at (no spam) gmail.com> wrote:
[quote:35b11ef9f0]On Jul 3, 7:22 pm, gearhead <nos... at (no spam) billburg.com> wrote:
...Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?
Soft iron will rust pretty quickly under the right conditions. Put it
in a Ziplok plastic bag, with a few tablespoons of water, and put it
in a warm place overnight. Washing with paint thinner, soap and clean
water will remove any grease that will slow the process.
If you can use hydrogen peroxide instead of water, the rusting will
probably go much faster.
Dangerous Bill
[/quote:35b11ef9f0]
Good on the H2O2. Something to try, anyway.
What about acidic versus basic solutions, for example what effect
would you get by adding a few grains of lye? I expect it might not
help, just asking out of curiosity. |
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| Mark Thorson... |
| Posted: Fri Jul 03, 2009 8:32 pm |
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gearhead wrote:
[quote:fd13d46b2c]
I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
[/quote:fd13d46b2c]
The fastest way to rust something is to put it
in a pure oxygen atmosphere. Condensing a little
moisture on it will also speed up rust formation. |
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| Michael Robinson... |
| Posted: Fri Jul 03, 2009 8:45 pm |
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"Mark Thorson" <nospam at (no spam) sonic.net> wrote in message
news:4A4EBF40.F7496D14 at (no spam) sonic.net...
[quote:2e85ae829d]gearhead wrote:
I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
The fastest way to rust something is to put it
in a pure oxygen atmosphere. Condensing a little
moisture on it will also speed up rust formation.
[/quote:2e85ae829d]
Unfortunately, I don't see an oxygen tank in the budget. |
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| Salmon Egg... |
| Posted: Fri Jul 03, 2009 9:59 pm |
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In article <tnz3m.13752$Qk7.702 at (no spam) newsfe22.iad>,
"Michael Robinson" <nospam at (no spam) billburg.com> wrote:
[quote:3fb19b68f8]"Mark Thorson" <nospam at (no spam) sonic.net> wrote in message
news:4A4EBF40.F7496D14 at (no spam) sonic.net...
gearhead wrote:
I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
The fastest way to rust something is to put it
in a pure oxygen atmosphere. Condensing a little
moisture on it will also speed up rust formation.
Unfortunately, I don't see an oxygen tank in the budget.
[/quote:3fb19b68f8]
Would 3% drugstore hydrogen peroxide do the job? I think it is worth a
trial.
Bill
--
Most people go to college to get their missing high school education. |
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| Salmon Egg... |
| Posted: Fri Jul 03, 2009 10:01 pm |
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Guest
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In article
<f39cb8a6-a0ab-4822-86f4-dc781d6996d3 at (no spam) b15g2000yqd.googlegroups.com>,
gearhead <nospam at (no spam) billburg.com> wrote:
[quote:dfbb623014]Good on the H2O2. Something to try, anyway.
What about acidic versus basic solutions, for example what effect
would you get by adding a few grains of lye? I expect it might not
help, just asking out of curiosity.
[/quote:dfbb623014]
It would certainly help clean off any oils.
Bill
--
Most people go to college to get their missing high school education. |
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| Carl Ijames... |
| Posted: Fri Jul 03, 2009 10:59 pm |
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Guest
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Chlorine bleach is one of the fastest ways I know to rust steel, even better
if you toss in some table salt.
-----
Regards,
Carl Ijames
"gearhead" <nospam at (no spam) billburg.com> wrote in message
news:2d22b6a1-b85a-4975-bf2c-79431767611e at (no spam) c36g2000yqn.googlegroups.com...
[quote:cfb6b679b7]I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
Just getting it wet and letting it sit will take much too long. I
need a way to speed up the reaction. I've thought of putting the
steel in water and applying a voltage to it like electrolytic
cleaning, but backwards. I've read that electrolytic rust removal
involves applying a negative voltage to the workpiece and placing a
positive sacrificial electrode in the solution. So presumably I could
reverse the polarity and apply positive voltage to the workpiece if I
want it to rust. But from what I've read about electrolytic cleaning,
the positive electrode actually dissolves -- and I don't want that.
Perhaps if I use plain water instead of an electrolyte, the positive
electrode would not dissolve. Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?[/quote:cfb6b679b7] |
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| Frank... |
| Posted: Sat Jul 04, 2009 5:50 am |
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Guest
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On Jul 3, 10:22 pm, gearhead <nos... at (no spam) billburg.com> wrote:
[quote:a28dca02d6]I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
Just getting it wet and letting it sit will take much too long. I
need a way to speed up the reaction. I've thought of putting the
steel in water and applying a voltage to it like electrolytic
cleaning, but backwards. I've read that electrolytic rust removal
involves applying a negative voltage to the workpiece and placing a
positive sacrificial electrode in the solution. So presumably I could
reverse the polarity and apply positive voltage to the workpiece if I
want it to rust. But from what I've read about electrolytic cleaning,
the positive electrode actually dissolves -- and I don't want that.
Perhaps if I use plain water instead of an electrolyte, the positive
electrode would not dissolve. Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?
[/quote:a28dca02d6]
I would consider one of the browning formulas from this site:
http://www.geocities.com/thorvin.geo/browning_and_blueing_of_guns_and.htm
Browning and gun blueing give controlled oxidation of iron surface and
also protect from further rusting. |
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| Marvin... |
| Posted: Sat Jul 04, 2009 8:46 am |
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Guest
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gearhead wrote:
[quote:187384b72b]I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
Just getting it wet and letting it sit will take much too long. I
need a way to speed up the reaction. I've thought of putting the
steel in water and applying a voltage to it like electrolytic
cleaning, but backwards. I've read that electrolytic rust removal
involves applying a negative voltage to the workpiece and placing a
positive sacrificial electrode in the solution. So presumably I could
reverse the polarity and apply positive voltage to the workpiece if I
want it to rust. But from what I've read about electrolytic cleaning,
the positive electrode actually dissolves -- and I don't want that.
Perhaps if I use plain water instead of an electrolyte, the positive
electrode would not dissolve. Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?
[/quote:187384b72b]
Others have made some suggestions. But you may not succeed
in getting a heavy coating of rust. What makes rust
destructive is that the oxide tends to flake off the metal,
exposing more metal to rusting. On the other hand, aluminum
oxide sticks strongly to aluminum, so aluminum is often
coated by anodizing - creating a relatively thick oxide
layer by electrolysis. There is a special iron alloy that
forms adherent oxide layers. It allows rust to form, but the
rust doesn't destroy the metal because it doesn't flake off.
Rusting is an autocatalytic process, so the rate of rusting
increases once some rust has formed initially. That is why
it is so important to remove all rust before painting over
the metal. |
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| gearhead... |
| Posted: Sat Jul 04, 2009 10:46 am |
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Guest
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On Jul 4, 11:50 am, Frank <frank.logu... at (no spam) dol.net> wrote:
[quote:abafd83ac2]On Jul 3, 10:22 pm, gearhead <nos... at (no spam) billburg.com> wrote:
I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
Just getting it wet and letting it sit will take much too long. I
need a way to speed up the reaction. I've thought of putting the
steel in water and applying a voltage to it like electrolytic
cleaning, but backwards. I've read that electrolytic rust removal
involves applying a negative voltage to the workpiece and placing a
positive sacrificial electrode in the solution. So presumably I could
reverse the polarity and apply positive voltage to the workpiece if I
want it to rust. But from what I've read about electrolytic cleaning,
the positive electrode actually dissolves -- and I don't want that.
Perhaps if I use plain water instead of an electrolyte, the positive
electrode would not dissolve. Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?
I would consider one of the browning formulas from this site:
http://www.geocities.com/thorvin.geo/browning_and_blueing_of_guns_and...
Browning and gun blueing give controlled oxidation of iron surface and
also protect from further rusting.
[/quote:abafd83ac2]
Okay, the reason I want rust on this wire is to act as electrical
insulation. I am winding the wire around a metal object and using the
wire as a heating element. If there is something other than rust,
easier or more effective, I'd be interested in knowing about it.
Would browning and bluing work as electrical insulation? I confess I
haven't read your link yet. |
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| gearhead... |
| Posted: Sat Jul 04, 2009 11:08 am |
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Guest
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On Jul 4, 11:50 am, Frank <frank.logu... at (no spam) dol.net> wrote:
[quote:3d12095b4b]On Jul 3, 10:22 pm, gearhead <nos... at (no spam) billburg.com> wrote:
I have some steel I just bought for a project. I need this steel to
develop a heavy coating of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge. I already washed it
to get any oil off.
Just getting it wet and letting it sit will take much too long. I
need a way to speed up the reaction. I've thought of putting the
steel in water and applying a voltage to it like electrolytic
cleaning, but backwards. I've read that electrolytic rust removal
involves applying a negative voltage to the workpiece and placing a
positive sacrificial electrode in the solution. So presumably I could
reverse the polarity and apply positive voltage to the workpiece if I
want it to rust. But from what I've read about electrolytic cleaning,
the positive electrode actually dissolves -- and I don't want that.
Perhaps if I use plain water instead of an electrolyte, the positive
electrode would not dissolve. Or maybe there's some chemical I can
use on the steel that will make it start rusting right away, and I
wouldn't have to resort to electrolysis. I'm no chemist.
How would I go about this?
I would consider one of the browning formulas from this site:
http://www.geocities.com/thorvin.geo/browning_and_blueing_of_guns_and...
Browning and gun blueing give controlled oxidation of iron surface and
also protect from further rusting.
[/quote:3d12095b4b]
It just happens I have some anhydrous ferric chloride powder. Your
link shows some formulas that include ferric chloride.
I submerged my coil of wire in drugstore hydrogen peroxide for a few
hours and it gathered noticeable rust, but it's kind of patchy. Maybe
I didn't do a good job cleaning the oil off.
I bought the ferric chloride to use as a copper etchant to make
printed circuit boards. Never got around to it. I might try it on
the steel wire and see what happens. |
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| N:dlzc D:aol T:com (dlzc)... |
| Posted: Sat Jul 04, 2009 4:17 pm |
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Guest
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Dear gearhead:
"gearhead" <nospam at (no spam) billburg.com> wrote in message
news:3f6bc068-12f0-4e38-91da-9288be28c56d at (no spam) q11g2000yqi.googlegroups.com...
On Jul 4, 11:50 am, Frank <frank.logu... at (no spam) dol.net> wrote:
[quote:c72334e200]On Jul 3, 10:22 pm, gearhead <nos... at (no spam) billburg.com> wrote:
I have some steel I just bought for a project.
I need this steel to develop a heavy coating
of rust. It is ordinary cheap steel, not
galvanized. A coil of wire about 16 or 17 gauge.
I already washed it to get any oil off.
I would consider one of the browning formulas
from this site:
link now broken by Google.Groups
Browning and gun blueing give controlled
oxidation of iron surface and also protect from
further rusting.
Okay, the reason I want rust on this wire is
to act as electrical insulation.
[/quote:c72334e200]
Rust is a very poor electrical insulator, among the lowest
resistivites of metal oxides.
[quote:c72334e200]I am winding the wire around a metal object
and using the wire as a heating element. If
there is something other than rust, easier or
more effective, I'd be interested in knowing
about it.
[/quote:c72334e200]
nichrorme in alumina is the usual suspect for this, as iron does
not have a particularly high resistivity per foot. Even if you
rust it first. Additionally, it softens and breaks, spalling off
any "rust insulation", and does not run to as high a temperature
before fully oxidizing as nichrome can.
David A. Smith |
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| gearhead... |
| Posted: Sat Jul 04, 2009 4:56 pm |
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On Jul 4, 7:55 pm, Salmon Egg <Salmon... at (no spam) sbcglobal.net> wrote:
[quote:8df9ba7fcd]In article
3f6bc068-12f0-4e38-91da-9288be28c... at (no spam) q11g2000yqi.googlegroups.com>,
gearhead <nos... at (no spam) billburg.com> wrote:
Okay, the reason I want rust on this wire is to act as electrical
insulation. I am winding the wire around a metal object and using the
wire as a heating element. If there is something other than rust,
easier or more effective, I'd be interested in knowing about it.
Would browning and bluing work as electrical insulation? I confess I
haven't read your link yet.
Relying upon rust as an insulator is looking for trouble, I would be
very surprised if you do not get shorts much faster than you can cure
them.
I would expect that nichrome would be much more reliable, It does not
have insulation. Ceramic forms are available for winding nichrome
resistance wire spaced from adjoining turns. You could use formvar
coated copper wire if it is thin enough and what temperature you wish to
reach.
Can't use ceramic forms, and the only wire I'm familiar with that has[/quote:8df9ba7fcd]
varnish type insulation is copper magnet wire. Copper would not make
a good heating element.
I'm heating at least 12 ft of quarter inch tubing. Efficiency is
important; whatever I use to isolate the heating element from the
tubing needs to be as thermally conductive as possible. So I thought
of rust, but I guess that's just not a very good idea. I suppose it
would make more sense just to paint the tubing. |
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| Salmon Egg... |
| Posted: Sat Jul 04, 2009 5:55 pm |
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Guest
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In article
<3f6bc068-12f0-4e38-91da-9288be28c56d at (no spam) q11g2000yqi.googlegroups.com>,
gearhead <nospam at (no spam) billburg.com> wrote:
[quote:af33ba89e3]Okay, the reason I want rust on this wire is to act as electrical
insulation. I am winding the wire around a metal object and using the
wire as a heating element. If there is something other than rust,
easier or more effective, I'd be interested in knowing about it.
Would browning and bluing work as electrical insulation? I confess I
haven't read your link yet.
[/quote:af33ba89e3]
Relying upon rust as an insulator is looking for trouble, I would be
very surprised if you do not get shorts much faster than you can cure
them.
I would expect that nichrome would be much more reliable, It does not
have insulation. Ceramic forms are available for winding nichrome
resistance wire spaced from adjoining turns. You could use formvar
coated copper wire if it is thin enough and what temperature you wish to
reach.
I once built a oven for growing organic scintillation crystals. The oven
itself was made from stainless steel cans. I coated it with some form of
sauereisen cement. I think that it may still be available. Nichrome was
hand wound on this coating, More sauereisen was used to cover the
nichrome and hold ity in place,
Bill
--
Most people go to college to get their missing high school education. |
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