I was making another clone of my miniature sundials. On this occasion
I thought I would try a few things differently. Amongst others I
decided to soft-solder the brass 0.020" foil to the steel substrate.
Normally I glue them together with Goop.

The soldering went smoothly (except for having to buy a bigger
soldering iron). I proceeded to machine the piece in the normal way
yesterday and today I put it together:

http://www.flickr.com/photos/2768312...in/photostream

The etching is a bit raggedy due to high current density (I was also
trying a new bath) but otherwise things looked normal until I noticed
the fresh rust on the inside of the ring:

http://www.flickr.com/photos/2768312...in/photostream

I interpret this as caused by the acid-based flux leaking onto the
freshly exposed steel. This raises the question of what to do about
this in future. Clealy no amount of thorough cleaning will get rid of
the flux that is hidden until exposed by turning/boring. Maybe I shall
go back to using rosin dissolved in alcohol as flux.

Michael Koblic,
Campbell River, BC

On 1/7/2013 4:29 PM, wrote:
I was making another clone of my miniature sundials. On this occasion
I thought I would try a few things differently. Amongst others I
decided to soft-solder the brass 0.020" foil to the steel substrate.
Normally I glue them together with Goop.

The soldering went smoothly (except for having to buy a bigger
soldering iron). I proceeded to machine the piece in the normal way
yesterday and today I put it together:

http://www.flickr.com/photos/2768312...in/photostream

The etching is a bit raggedy due to high current density (I was also
trying a new bath) but otherwise things looked normal until I noticed
the fresh rust on the inside of the ring:

http://www.flickr.com/photos/2768312...in/photostream

I interpret this as caused by the acid-based flux leaking onto the
freshly exposed steel. This raises the question of what to do about
this in future. Clealy no amount of thorough cleaning will get rid of
the flux that is hidden until exposed by turning/boring. Maybe I shall
go back to using rosin dissolved in alcohol as flux.

Michael Koblic,
Campbell River, BC

Nice work.

Isn't the dissimilar metal problem gonna pop up sooner or later?
Steel is gonna rust.
What's the cost differential for making the whole disk out of brass?

Sounds like the goop was working??

On Mon, 07 Jan 2013 17:25:19 -0800, mike wrote:

[...]


Nice work.

Thank you.

Isn't the dissimilar metal problem gonna pop up sooner or later?
Steel is gonna rust.
What's the cost differential for making the whole disk out of brass?

Sounds like the goop was working??

I have had no problem with the glued pieces even after a relatively
long period of time (indoors) and with relatively little surface
finish protection (wax or even just Autosol). The dramatic part in
this case was the rust appearing in less than 24 hours.

The Goop works fine (the *only* glue that would do the job BTW!) but
it can take up to 72 hours to cure completely and allow machining.

As to the economics of the whole thing it is kind of complex: To get a
similar size dial (2.5" diameter, 3/16" thick) the cheapest way would
be to buy 2.5" round brass and slice it up. A very rough calculation
making all kinds of assumptions about machining losses shows that my
way is about 30% cheaper. I use 1" washers so a lot of cutting is
already done. I could bring the cost down even further if I could get
mild steel disks stamped out but when I tried this (at ridiculous
shipping costs) it did not prove to be a free lunch either.

I have done many all-steel dials, too, and people seem to like them
just as much as the brass ones. However, in the current economy,
selling them at prices that would barely cover the costs is proving
difficult. Hence I am looking for different methods of making them. It
is a slow process :-)

Michael Koblic,
Campbell River, BC

On Tue, 08 Jan 2013 18:39:01 -0800, wrote:

On Mon, 07 Jan 2013 17:25:19 -0800, mike wrote:

[...]


Nice work.

Thank you.

Isn't the dissimilar metal problem gonna pop up sooner or later?
Steel is gonna rust.
What's the cost differential for making the whole disk out of brass?

Sounds like the goop was working??

I have had no problem with the glued pieces even after a relatively
long period of time (indoors) and with relatively little surface
finish protection (wax or even just Autosol). The dramatic part in
this case was the rust appearing in less than 24 hours.

The Goop works fine (the *only* glue that would do the job BTW!) but
it can take up to 72 hours to cure completely and allow machining.

As to the economics of the whole thing it is kind of complex: To get a
similar size dial (2.5" diameter, 3/16" thick) the cheapest way would
be to buy 2.5" round brass and slice it up. A very rough calculation
making all kinds of assumptions about machining losses shows that my
way is about 30% cheaper. I use 1" washers so a lot of cutting is
already done. I could bring the cost down even further if I could get
mild steel disks stamped out but when I tried this (at ridiculous
shipping costs) it did not prove to be a free lunch either.

I have done many all-steel dials, too, and people seem to like them
just as much as the brass ones. However, in the current economy,
selling them at prices that would barely cover the costs is proving
difficult. Hence I am looking for different methods of making them. It
is a slow process :-)

Michael Koblic,
Campbell River, BC

An old Gorton Pantograph and suitble small cutters? Cheap, easy

Gunner

The methodology of the left has always been:

1. Lie
2. Repeat the lie as many times as possible
3. Have as many people repeat the lie as often as possible
4. Eventually, the uninformed believe the lie
5. The lie will then be made into some form oflaw
6. Then everyone must conform to the lie

On 1/8/2013 6:39 PM, wrote:
On Mon, 07 Jan 2013 17:25:19 -0800, wrote:

[...]


Nice work.

Thank you.

Isn't the dissimilar metal problem gonna pop up sooner or later?
Steel is gonna rust.
What's the cost differential for making the whole disk out of brass?

Sounds like the goop was working??

I have had no problem with the glued pieces even after a relatively
long period of time (indoors) and with relatively little surface
finish protection (wax or even just Autosol). The dramatic part in
this case was the rust appearing in less than 24 hours.

The Goop works fine (the *only* glue that would do the job BTW!) but
it can take up to 72 hours to cure completely and allow machining.

As to the economics of the whole thing it is kind of complex: To get a
similar size dial (2.5" diameter, 3/16" thick) the cheapest way would
be to buy 2.5" round brass and slice it up. A very rough calculation
making all kinds of assumptions about machining losses shows that my
way is about 30% cheaper. I use 1" washers so a lot of cutting is
already done. I could bring the cost down even further if I could get
mild steel disks stamped out but when I tried this (at ridiculous
shipping costs) it did not prove to be a free lunch either.

I have done many all-steel dials, too, and people seem to like them
just as much as the brass ones. However, in the current economy,
selling them at prices that would barely cover the costs is proving
difficult. Hence I am looking for different methods of making them. It
is a slow process :-)

Michael Koblic,
Campbell River, BC


At the risk of stating the obvious...what are you marketing?

A timepiece?
A gift item that ends up in a drawer?
A mantle piece that gets viewed from afar?
A delivery vehicle for some time-related corporate catch phrase
or call to action?
A "quality item" that sits on your desk in the corner office
to be admired and handled as a status symbol, much like your Rolex?

You might be able to get away with a sawed-off section of plastic pipe
instead
of the steel disk. Maybe you can't see the pipe section at all.

While cost reduction is an admirable goal, it's sometimes helpful
to start with a clean slate and try to meet the need with a slightly
different, lower-cost design.

Don't overlook the opportunity to hook on price and upsell to the
quality item.

On 1/8/2013 2:29, wrote:
I was making another clone of my miniature sundials. On this occasion
I thought I would try a few things differently. Amongst others I
decided to soft-solder the brass 0.020" foil to the steel substrate.
Normally I glue them together with Goop.

The soldering went smoothly (except for having to buy a bigger
soldering iron). I proceeded to machine the piece in the normal way
yesterday and today I put it together:

http://www.flickr.com/photos/2768312...in/photostream

The etching is a bit raggedy due to high current density (I was also
trying a new bath) but otherwise things looked normal until I noticed
the fresh rust on the inside of the ring:

http://www.flickr.com/photos/2768312...in/photostream

I interpret this as caused by the acid-based flux leaking onto the
freshly exposed steel. This raises the question of what to do about
this in future. Clealy no amount of thorough cleaning will get rid of
the flux that is hidden until exposed by turning/boring. Maybe I shall
go back to using rosin dissolved in alcohol as flux.

Perhaps immerse it in hot citric acid solution for a while
at the end to get rid of rust and flux remains. I've noticed
citric acid is the wonder cleaning stuff - nonpoisonous,
water based, cheap and cleans rust and flux away really well.
Works fine for brazing fluxes too. It is the same stuff you
use for cleaning your coffee making machine!

I even cleaned my WEDM water container with citric acid.. It was
all green, rusty and dirty in the beginning with who knows what
metal remains on the walls there. Few times of hot citric acid
(as hot as water comes from tap, around 60C, and some citric
acid to it) and it is the normal clean stainless steel colour on
all walls again. Totally amazing!

On Tue, 08 Jan 2013 23:41:35 +0200, Kristian Ukkonen
wrote:

[...]

Perhaps immerse it in hot citric acid solution for a while
at the end to get rid of rust and flux remains. I've noticed
citric acid is the wonder cleaning stuff - nonpoisonous,
water based, cheap and cleans rust and flux away really well.
Works fine for brazing fluxes too. It is the same stuff you
use for cleaning your coffee making machine!

I even cleaned my WEDM water container with citric acid.. It was
all green, rusty and dirty in the beginning with who knows what
metal remains on the walls there. Few times of hot citric acid
(as hot as water comes from tap, around 60C, and some citric
acid to it) and it is the normal clean stainless steel colour on
all walls again. Totally amazing!

No doubt excellent for stainless steel. Unfortunately with mild steel
all you are doing is activating the steel surface for further rusting.

Michael Koblic,
Campbell River, BC

Assuming that you are talking about soft soldering, that is: tin/lead
solders---

The solution that I have used for the last 50+ years is this:
Don't use acid based flux. Instead, I use rosin based fluxes or those
that are used for electronic component soldering. You probably will need to
practice your pre-cleaning a little, as the rosin based flux isn't as
chemically active, but it'll work.

I know many tinsmiths who use acid based fluxes and then spend a lot of time
and care to get rid of the acid afterwards. While I am not a tinsmith in
any stretch of the imagination, the rosin core solder works well there,
too. And no worry about clean up, even 'tho I do use acetone to clean off
the "rosin" that shows.

Pete Stanaitis
----------------

In article ,
wrote:

I was making another clone of my miniature sundials. On this occasion
I thought I would try a few things differently. Amongst others I
decided to soft-solder the brass 0.020" foil to the steel substrate.
Normally I glue them together with Goop.

The soldering went smoothly (except for having to buy a bigger
soldering iron). I proceeded to machine the piece in the normal way
yesterday and today I put it together:

http://www.flickr.com/photos/2768312...in/photostream

The etching is a bit raggedy due to high current density (I was also
trying a new bath) but otherwise things looked normal until I noticed
the fresh rust on the inside of the ring:

http://www.flickr.com/photos/2768312...in/photostream

I interpret this as caused by the acid-based flux leaking onto the
freshly exposed steel. This raises the question of what to do about
this in future. Clealy no amount of thorough cleaning will get rid of
the flux that is hidden until exposed by turning/boring. Maybe I shall
go back to using rosin dissolved in alcohol as flux.

If I understand, you machine after soldering the brass to the steel. I
have a lot of trouble believing that the acid flux would penetrate solid
mild steel so far that peeling 0.050" off wouldn't solve the problem.

Use of rosin flux has been suggested, but that probably won't work very
well for steel. The traditional dodge is to tin the steel using acid
flux, wash the flux residue off with hot water and bicarbonate of soda,
and then solder brass to steel with plumbers flux (intended for
soldering copper pipe). Clean the flux off with acetone followed with
hot water.

I have also soldered cadmium-plated steel by mechanical cleaning
followed by soldering with plumbers flux.

Joe Gwinn

On Sat, 12 Jan 2013 17:58:37 -0500, Joseph Gwinn
wrote:

[...]

If I understand, you machine after soldering the brass to the steel. I
have a lot of trouble believing that the acid flux would penetrate solid
mild steel so far that peeling 0.050" off wouldn't solve the problem.

Not sure that I understand.

Use of rosin flux has been suggested, but that probably won't work very
well for steel. The traditional dodge is to tin the steel using acid
flux, wash the flux residue off with hot water and bicarbonate of soda,

This will remove all the flux that is accessible but not the flux that
is underneath the solder. My contention is that this "hidden" flux is
then exposed by machining and causes rusting on the freshly exposed
metal. One can argue that the cleaning should be repeated after the
machining but because of other processes involved this is not
feasible.

and then solder brass to steel with plumbers flux (intended for
soldering copper pipe). Clean the flux off with acetone followed with
hot water.

My understanding is that vast majority of plumbers' fluxes are acid
based, or, to be precise, zinc chloride and ammonium chloride based.
Mine certainly is..

Michael Koblic,
Campbell River, BC

In article ,
wrote:

On Sat, 12 Jan 2013 17:58:37 -0500, Joseph Gwinn
wrote:

[...]

If I understand, you machine after soldering the brass to the steel. I
have a lot of trouble believing that the acid flux would penetrate solid
mild steel so far that peeling 0.050" off wouldn't solve the problem.

Not sure that I understand.

The acid cannot penetrate that far into the metal, so the rusting was
from some other cause.

Said another way, if the acid did penetrate that far, you should change
metal suppliers.


Use of rosin flux has been suggested, but that probably won't work very
well for steel. The traditional dodge is to tin the steel using acid
flux, wash the flux residue off with hot water and bicarbonate of soda,

This will remove all the flux that is accessible but not the flux that
is underneath the solder. My contention is that this "hidden" flux is
then exposed by machining and causes rusting on the freshly exposed
metal. One can argue that the cleaning should be repeated after the
machining but because of other processes involved this is not
feasible.

There is no flux hidden in the metal to metal interface between solder
and steel. The solder displaced the flux, and/or entombed it,
preventing access to the air.

The critical flux residues are elsewhere. That's the reason for the hot
water wash and/or neutralizing bath (sodium bicarbonate).


and then solder brass to steel with plumbers flux (intended for
soldering copper pipe). Clean the flux off with acetone followed with
hot water.

My understanding is that vast majority of plumbers' fluxes are acid
based, or, to be precise, zinc chloride and ammonium chloride based.
Mine certainly is..

That is correct. However, if you look at old copper plumbing, you will
see that it doesn't matter. Soldering is a very old technology, having
been used by the Sumerians in 3000 BC.

War story. Before I knew better, I built a Heathkit VTVM (Vacuum Tube
Volt Meter) kit using plumbers flux and solder, using a 250-watt Wen
soldering gun. This would be in the late 1950s. I still have that
VTVM, and it still works. Also still have the Wen.

Joe Gwinn

On Sun, 13 Jan 2013 23:05:38 -0500, Joseph Gwinn
wrote:

In article ,
wrote:

On Sat, 12 Jan 2013 17:58:37 -0500, Joseph Gwinn
wrote:

[...]

If I understand, you machine after soldering the brass to the steel. I
have a lot of trouble believing that the acid flux would penetrate solid
mild steel so far that peeling 0.050" off wouldn't solve the problem.

Not sure that I understand.

The acid cannot penetrate that far into the metal, so the rusting was
from some other cause.

Agreed.

Said another way, if the acid did penetrate that far, you should change
metal suppliers.


Use of rosin flux has been suggested, but that probably won't work very
well for steel. The traditional dodge is to tin the steel using acid
flux, wash the flux residue off with hot water and bicarbonate of soda,

This will remove all the flux that is accessible but not the flux that
is underneath the solder. My contention is that this "hidden" flux is
then exposed by machining and causes rusting on the freshly exposed
metal. One can argue that the cleaning should be repeated after the
machining but because of other processes involved this is not
feasible.

There is no flux hidden in the metal to metal interface between solder
and steel. The solder displaced the flux, and/or entombed it,
preventing access to the air.

Agreed again. I contend that machining exposed one of these "entombed"
areas.

The critical flux residues are elsewhere. That's the reason for the hot
water wash and/or neutralizing bath (sodium bicarbonate).

This was done after the soldering but before machining.


and then solder brass to steel with plumbers flux (intended for
soldering copper pipe). Clean the flux off with acetone followed with
hot water.

My understanding is that vast majority of plumbers' fluxes are acid
based, or, to be precise, zinc chloride and ammonium chloride based.
Mine certainly is..

That is correct. However, if you look at old copper plumbing, you will
see that it doesn't matter. Soldering is a very old technology, having
been used by the Sumerians in 3000 BC.

It matters if you solder brass to mild steel.

Michael Koblic,
Campbell River, BC

On Mon, 14 Jan 2013 16:07:53 -0800, wrote:

On Sun, 13 Jan 2013 23:05:38 -0500, Joseph Gwinn
wrote:

In article ,
wrote:

On Sat, 12 Jan 2013 17:58:37 -0500, Joseph Gwinn
wrote:

[...]

If I understand, you machine after soldering the brass to the steel. I
have a lot of trouble believing that the acid flux would penetrate solid
mild steel so far that peeling 0.050" off wouldn't solve the problem.

Not sure that I understand.

The acid cannot penetrate that far into the metal, so the rusting was
from some other cause.

Agreed.

Said another way, if the acid did penetrate that far, you should change
metal suppliers.


Use of rosin flux has been suggested, but that probably won't work very
well for steel. The traditional dodge is to tin the steel using acid
flux, wash the flux residue off with hot water and bicarbonate of soda,

This will remove all the flux that is accessible but not the flux that
is underneath the solder. My contention is that this "hidden" flux is
then exposed by machining and causes rusting on the freshly exposed
metal. One can argue that the cleaning should be repeated after the
machining but because of other processes involved this is not
feasible.

There is no flux hidden in the metal to metal interface between solder
and steel. The solder displaced the flux, and/or entombed it,
preventing access to the air.

Agreed again. I contend that machining exposed one of these "entombed"
areas.

The critical flux residues are elsewhere. That's the reason for the hot
water wash and/or neutralizing bath (sodium bicarbonate).

This was done after the soldering but before machining.


and then solder brass to steel with plumbers flux (intended for
soldering copper pipe). Clean the flux off with acetone followed with
hot water.

My understanding is that vast majority of plumbers' fluxes are acid
based, or, to be precise, zinc chloride and ammonium chloride based.
Mine certainly is..

That is correct. However, if you look at old copper plumbing, you will
see that it doesn't matter. Soldering is a very old technology, having
been used by the Sumerians in 3000 BC.

It matters if you solder brass to mild steel.

Michael Koblic,
Campbell River, BC

Greetings Michael,
I've been reading this thread about your soldering and how you
mentioned using rosin flux. I was pretty sure it would work but I
tried it any way. Soldering clean steel and brass was easy with plain
old rosin core solder. After the first test I applied more solder to
each piece, more than needed to join the two pieces, and then used a
rag with lard on it to wipe away the excess and just leave a thin
coat. Sorta like tinning a copper or steel bowl. I then cleaned off
the lard residue with acetone and laid the brass on the steel, heated
the stack, and then pressed down with a steel block to squeeze any
solder out for the thinnest possible solder line. My little test
worked well. Maybe you can use some of the above info.
Eric

In article ,
wrote:

On Sun, 13 Jan 2013 23:05:38 -0500, Joseph Gwinn
wrote:

In article ,
wrote:

On Sat, 12 Jan 2013 17:58:37 -0500, Joseph Gwinn
wrote:

[...]

If I understand, you machine after soldering the brass to the steel. I
have a lot of trouble believing that the acid flux would penetrate solid
mild steel so far that peeling 0.050" off wouldn't solve the problem.

Not sure that I understand.

The acid cannot penetrate that far into the metal, so the rusting was
from some other cause.

Agreed.

Said another way, if the acid did penetrate that far, you should change
metal suppliers.


Use of rosin flux has been suggested, but that probably won't work very
well for steel. The traditional dodge is to tin the steel using acid
flux, wash the flux residue off with hot water and bicarbonate of soda,

This will remove all the flux that is accessible but not the flux that
is underneath the solder. My contention is that this "hidden" flux is
then exposed by machining and causes rusting on the freshly exposed
metal. One can argue that the cleaning should be repeated after the
machining but because of other processes involved this is not
feasible.

There is no flux hidden in the metal to metal interface between solder
and steel. The solder displaced the flux, and/or entombed it,
preventing access to the air.

Agreed again. I contend that machining exposed one of these "entombed"
areas.

The entombed areas are very close to the surface, and with sufficient
machining depth the tombs should be removed.


The critical flux residues are elsewhere. That's the reason for the hot
water wash and/or neutralizing bath (sodium bicarbonate).

This was done after the soldering but before machining.

OK. That handles the surface.


and then solder brass to steel with plumbers flux (intended for
soldering copper pipe). Clean the flux off with acetone followed with
hot water.

My understanding is that vast majority of plumbers' fluxes are acid
based, or, to be precise, zinc chloride and ammonium chloride based.
Mine certainly is..

That is correct. However, if you look at old copper plumbing, you will
see that it doesn't matter. Soldering is a very old technology, having
been used by the Sumerians in 3000 BC.

It matters if you solder brass to mild steel.

Only of the environment supports galvanic corrosion, which may be the
case. But this has nothing to do with flux products, which are either
entombed (no access to the atmosphere or visibility at the surface) or
removed and/or neutralized.

Galvanic corrosion can occur if a piece of steel is electrically
connected to a piece of brass, by any means. Soldering works, but is
not required. Bolting together would work too.

Another poster (etpm) said that he was able to solder brass to
well-cleaned steel with rosin-core solder; this uses activated rosin
(activated flux contains some kind of acid dissolved in the rosin). The
end result is brass and steel electrically connected.

So, the deeper and long-term problem may not be how to manufacture the
brass-steel composite per se, but rather how to control galvanic
corrosion in the resulting assembly. Copper or brass or nickel plating
of the steel component may be required. Or electrical isolation of the
brass and steel components from one another.

http://en.wikipedia.org/wiki/Galvanic_series

Joe Gwinn