I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!
I've not soldered brass before. Any suggestions?

Cleanliness, Easiflow No 2 and a good heat should do it.

On Fri, 16 Oct 2009 22:36:18 -0700 (PDT), Matty F wrote:

... solder the bottom on with silver solder. They need to be oil-tight!

2mm sounds a bit thick for some thing quite small. Think I would use
thinner plate and fold the sides up so that you have a mechanicaly
stable box with minimal gaps at the corners then just solder the
seams.

A loose base and sides I can envisage being a nightmare to solder
unless you can hold all the bits in place and do it almost in one
hit. Even with folded loop sides and loose base might be fun.

I've not soldered brass before. Any suggestions?

Just like soldering copper. Not a problem.

--
Cheers
Dave.

Matty F wrote:
I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!
I've not soldered brass before. Any suggestions?

Its fine. Use plumbers flux and a BIG iron or small blowlamp.

On Oct 17, 7:47 pm, "Dave Liquorice"
wrote:
On Fri, 16 Oct 2009 22:36:18 -0700 (PDT), Matty F wrote:
... solder the bottom on with silver solder. They need to be oil-tight!

2mm sounds a bit thick for some thing quite small. Think I would use
thinner plate and fold the sides up so that you have a mechanicaly
stable box with minimal gaps at the corners then just solder the
seams.

A loose base and sides I can envisage being a nightmare to solder
unless you can hold all the bits in place and do it almost in one
hit. Even with folded loop sides and loose base might be fun.

I've not soldered brass before. Any suggestions?

Just like soldering copper. Not a problem.

The original is cast brass and is 3 to 4 mm thick:
http://i37.tinypic.com/23lftd2.jpg
No it's not a toilet cistern!
It has to withstand quite a lot of vibration and being kicked by heavy
boots.

I thought I would have the base and back in one piece and the other
three sides as another piece.

On Sat, 17 Oct 2009 02:10:24 -0700 (PDT), Matty F wrote:

The original is cast brass and is 3 to 4 mm thick:
http://i37.tinypic.com/23lftd2.jpg

Apart from the missing nut that looks in perfect condition. Is yours
a duplicate for some where else?

I thought I would have the base and back in one piece and the other
three sides as another piece.

Makes the folding easier if nothing else. You can probably tack
solder that those two peices into a mechanicaly stable object then
solder along the join in a single pass with a small blow torch. Or
you could try brazing it, which would be stronger than soft
soldering.

--
Cheers
Dave.

Stephen Howard wrote:

If you're canny you can use a couple of sticks of solder with
different melt points ( use high/low with adjacent joints ).

When I was about 11 or 12 we did silver soldering for jewelery at school
(no precious metals or stones involved though :-) ). ISTR having three
or four different grades of solder so you could start with the highest
and work down to do several joints without melting the previous one.

Wouldn't be allowed now, of course, and I'm only 27.

Pete

On Sat, 17 Oct 2009 02:10:24 -0700 (PDT), Matty F
wrote:

On Oct 17, 7:47 pm, "Dave Liquorice"
wrote:
On Fri, 16 Oct 2009 22:36:18 -0700 (PDT), Matty F wrote:
... solder the bottom on with silver solder. They need to be oil-tight!

2mm sounds a bit thick for some thing quite small. Think I would use
thinner plate and fold the sides up so that you have a mechanicaly
stable box with minimal gaps at the corners then just solder the
seams.

A loose base and sides I can envisage being a nightmare to solder
unless you can hold all the bits in place and do it almost in one
hit. Even with folded loop sides and loose base might be fun.

I've not soldered brass before. Any suggestions?

Just like soldering copper. Not a problem.

The original is cast brass and is 3 to 4 mm thick:
http://i37.tinypic.com/23lftd2.jpg
No it's not a toilet cistern!
It has to withstand quite a lot of vibration and being kicked by heavy
boots.

I thought I would have the base and back in one piece and the other
three sides as another piece.


Soldering small brass boxes can be problematic in that the joint
you're working on ideally needs to be horizontal. Sooner or later
it'll be sod's law that there'll be an adjacent vertical soldered
joint - and before you know it all your solder will run out of it
unless you have a very good gas gun that delivers an accurate flame
and you're very quick with your hands.
I'd use a paste flux, such as La-Co, as it offers some slight cooling
over previously soldered joints and won't contaminate the joint you're
working on if it runs down.

If the box has to withstand a hefty kick I'd be inclined to silver
solder it - 2mm brass isn't going to give you enough surface area to
ensure the joints won't give way if one of the sides cops a whack
straight on.
You'll need to get the brass up to red heat, but as silver solder
doesn't flow as freely as soft solder you won't have quite so many
problems with unsoldering joints.
If you're canny you can use a couple of sticks of solder with
different melt points ( use high/low with adjacent joints ).
A small tub of JM tenacity No6 powdered flux will last you almost a
lifetime.

Regards,




--
Steve ( out in the sticks )
Email: Take time to reply: timefrom_usenet{at}gmx.net

Matty F submitted this idea :
I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!
I've not soldered brass before. Any suggestions?

Brass is easy to solder, but you might be in bother holding the corners
in place. 2mm in such small pieces might be impossible to fold to
provide an overlap, so could you use some thin ready made brass angle
in the corners? Model supplies type places would have the angle in
stock.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

On 17 Oct, 06:36, Matty F wrote:
I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!

First of all, soft or silver? You'll have a pig of a job soft-
soldering lubricators like this, because of the thickness of the brass
and the amount of heat you'd need to apply.

If you do go for soft, forget irons, forget torches, and go for
sweating them together.

This is basically heavy tinning in the joining areas, assembling cold,
dribbling liquid flux in (Baker's fluid) and then heating slowly in a
furnace (or best approximation with a few firebricks and a broad torch
flame), until the solder runs together. You're reliant on capillary
action here, and no amount of faffing about with an iron or individual
jointing with a torch will give you a reliable leak-proof joint in
thick brass.

Mechanical fit is important. It's too thick to fold and yet get a
square edge, so you're building up from flat sheets. I'd leave the
front, back and base over-long, then file them down into your cuboid
afterwards. I'd also use a tiny chisel to raise a few tiny burrs on
the inside of the base as a backstop for the sides, then wire the box
up with soft iron wire before heating. You can even use iron
toolmaker's clamps inside (whitewashed to stop them sticking), or even
(easiest for bulk runs) make up a welded or ground steel inner
scaffold block (with big chamfers) so that you can clamp the brass
plates easily into place onto it.

Personally I'd silver solder it. Viscosity is lower and capillary
attraction greater, so it just loves to flow nicely and give a well-
sealed joint. Again, pre-build the load and furnace it, rather than
taking a torch around inch by inch. Silver solder is expensive (but so
is time), so make the parts fit well. Again, I'd make the edges
straight, stack the box up with overlaps, solder and then trim
afterwards.

Brazing is possible, looks good (colour match), but hard work. You
have a tiny (if any!) difference in melting point between a hard sheet
brass and a soft spelter.

Cleanliness beforehand is important. If you have any lead solder
around, stick with using lead, as silver soldering over old lead
residue is a right old pain.

Silver solder used to (and bought via eBay still does) contain
cadmium, which makes it easier to work with and the fumes toxic.
Silver soldering flux (Easyflow) is fluorides, so that's pretty nasty
when heated too. Ventilate!

You need a firebrick hearth and plenty of bricks around it before you
do any of this stuff. Firebricks are cheaper than bigger torches and
encourage more even heating, with less distortion.

In message
,
Matty F writes
It has to withstand quite a lot of vibration and being kicked by heavy
boots.
I offer this just for interest, but it might be relevant.

When we built the yacht in the garage, I took the door off an old
fridge, folded a piece of brass to be easy to clip over the bottom of
the icebox and soldered mainly copper tube offcuts, but all sorts of
other junk to it. A sheet of polythene guided the dripping condensate
into the salad tray at the bottom, which was emptied every evening.

This was my attempt to dehumidify during the build.

Towards the end of the 5 years the copper tubes started to fall off.
Inspection showed that the solder had changed to what looked like a
crystalline form - sort of like a really terrible dry joint, but much
more obvious.

Not certain what caused this. I don't think it was due to anything like
different expansion/contraction rates between brass and copper, as the
fridge just ran continuously for the whole 5 years. It might have been
long term vibration in the cold.
--
Bill

On Oct 17, 11:18 pm, "Dave Liquorice"
wrote:
On Sat, 17 Oct 2009 02:10:24 -0700 (PDT), Matty F wrote:
The original is cast brass and is 3 to 4 mm thick:
http://i37.tinypic.com/23lftd2.jpg

Apart from the missing nut that looks in perfect condition. Is yours
a duplicate for some where else?

That box is similar to the four that I need to make. I'm still waiting
for photos of the original.

I thought I would have the base and back in one piece and the other
three sides as another piece.

Makes the folding easier if nothing else. You can probably tack
solder that those two peices into a mechanicaly stable object then
solder along the join in a single pass with a small blow torch. Or
you could try brazing it, which would be stronger than soft
soldering.

Hah! I better investigate brazing. I'm tempted to have a look at
getting it cast in a foundry. This may be harder than I thought.

In message
,
Matty F writes
Hah! I better investigate brazing. I'm tempted to have a look at
getting it cast in a foundry. This may be harder than I thought.

Should be a piece of cake to solder, silver or soft. Brazing is a
different matter, IIRC you're risking melting the workpiece when you
reach the temperatures required if it's made of brass.

Brass is a doddle to solder given sufficient heat, all you need to do is
assemble the box and wire it together using steel wire. Nothing to say
you couldn't use some brass machine screws to hold the box together and
then file the protruding bits off later either!

If you can anneal the brass and fold shapes to form a box then it
becomes easier still.
You can even cast brass at home if you are sufficiently adventurous, I
quite fancy having a go at lost wax casting.
--
Clint Sharp

On 17 Oct, 18:41, Bill wrote:

Towards the end of the 5 years the copper tubes started to fall off.
Inspection showed that the solder had changed to what looked like a
crystalline form - sort of like a really terrible dry joint, but much
more obvious.

Web search for "grey tin", and the story of how Napoleon was defeated
in Russia because his army's trousers fell down.

On 17 Oct, 22:29, Clint Sharp wrote:

You can even cast brass at home if you are sufficiently adventurous, I
quite fancy having a go at lost wax casting.

Brass is a pig to cast. Bronze is _so_ much easier.

This wouldn't be an easy shape to cast, as you have to flow into those
deep, thin sides. Not a hard bit of patternmaking, but I'd use
Petrobond sand (by the kg from mutr.co.uk) and a traditional open
mould, not my usual lost foam.

Apart from lost wax, the "lost frog" process is amusing...

Andy Dingley wrote:
On 17 Oct, 18:41, Bill wrote:

Towards the end of the 5 years the copper tubes started to fall off.
Inspection showed that the solder had changed to what looked like a
crystalline form - sort of like a really terrible dry joint, but much
more obvious.

Web search for "grey tin", and the story of how Napoleon was defeated
in Russia because his army's trousers fell down.

Hmm Wiki states that bismuth or antimony may be used instead of lead.
Bit they are ,are they not, aabout 1000 times deadlier than lead?

The Natural Philosopher wrote:
Andy Dingley wrote:
On 17 Oct, 18:41, Bill wrote:

Towards the end of the 5 years the copper tubes started to fall off.
Inspection showed that the solder had changed to what looked like a
crystalline form - sort of like a really terrible dry joint, but much
more obvious.

Web search for "grey tin", and the story of how Napoleon was defeated
in Russia because his army's trousers fell down.

Hmm Wiki states that bismuth or antimony may be used instead of lead.
Bit they are ,are they not, aabout 1000 times deadlier than lead?

Maybe - I really don't know - but medicines such as Pepto-Bismol contain
bismuth subsalicylate. And bismuth-containing medicines were used by Dr
Barry J. Marshall and Dr J. Robin Warren in their work on Helicobacter
pylori.

And your self-same source says this of Bismuth:

Scientific literature concurs with the idea that bismuth and its
compounds are less toxic than lead or its other periodic table
neighbours (antimony, polonium)[22] and that it isn't bioaccumulative.
Its biological half-life for whole-body retention is 5 days but it can
remain in the kidney for years in patients treated with bismuth
compounds[23]. In the industry, it is considered as one of the least
toxic heavy metals.
http://en.wikipedia.org/wiki/Bismuth

--
Rod

On Oct 17, 10:10*am, Matty F wrote:

The original is cast brass and is 3 to 4 mm thick:http://i37.tinypic.com/23lftd2.jpg
No it's not a toilet cistern!
It has to withstand quite a lot of vibration and being kicked by heavy
boots.

I really cant see soldered 2mm brass doing that.


NT

In message
, Andy
Dingley writes
On 17 Oct, 22:29, Clint Sharp wrote:

You can even cast brass at home if you are sufficiently adventurous, I
quite fancy having a go at lost wax casting.

Brass is a pig to cast. Bronze is _so_ much easier.
I know bronze is fairly easy to work with, what are the pitfalls with
brass? I've been told it was fairly straightforward.

Apart from lost wax, the "lost frog" process is amusing...
Lost frog? OK, I'll go Google.
--
Clint Sharp

On 18 Oct, 00:29, The Natural Philosopher
wrote:

Hmm Wiki states that bismuth or antimony may be used instead of lead.
Bit they are ,are they not, aabout 1000 times deadlier than lead?

Bismuth is the safe replacement for lead shot. Nor do I see what this
has to do with tin.

On 18 Oct, 15:52, Clint Sharp wrote:

Brass is a pig to cast. Bronze is _so_ much easier.

I know bronze is fairly easy to work with, what are the pitfalls with
brass? I've been told it was fairly straightforward.

It's straightforward to "cast" it, harder to get a reliable pour in
such a long thin section as this.

It also depends on your brass alloy. It's easier if you have something
that can be taken to a higher temperature (without dezincing) and
remains fluid to a lower temperature. Tin bronzes will generally be an
easier route to this than zinc brasses.

Apart from lost wax, the "lost frog" process is amusing...

Lost frog? OK, I'll go Google.

Frog-feet cast in silver, but missing out the usual intermediate
moulding steps. Burn-out is a bit stinky...

In message
,
Andy Dingley writes
It's straightforward to "cast" it, harder to get a reliable pour in
such a long thin section as this.
Ahh, I see.

It also depends on your brass alloy. It's easier if you have something
that can be taken to a higher temperature (without dezincing) and
remains fluid to a lower temperature.
Longer working time essentially, contact with the mould cools it to a
point where it's no longer free flowing or even solid, could you not
pre-heat the mould or even work up a spin casting system I wonder?

Personal preference would be to make the walls thicker
Tin bronzes will generally be an
easier route to this than zinc brasses.


Frog-feet cast in silver, but missing out the usual intermediate
moulding steps. Burn-out is a bit stinky...
Nice, think I'll pass on that one.

--
Clint Sharp

On Oct 19, 11:43 am, Andy Dingley wrote:
On 18 Oct, 15:52, Clint Sharp wrote:

Brass is a pig to cast. Bronze is _so_ much easier.

I know bronze is fairly easy to work with, what are the pitfalls with
brass? I've been told it was fairly straightforward.

It's straightforward to "cast" it, harder to get a reliable pour in
such a long thin section as this.

It also depends on your brass alloy. It's easier if you have something
that can be taken to a higher temperature (without dezincing) and
remains fluid to a lower temperature. Tin bronzes will generally be an
easier route to this than zinc brasses.

The sample was cast. Perhaps it was cast upside down like this:
http://i33.tinypic.com/2ijpvr7.jpg

except that the middle part of the hinge is thicker than the wall so
the pattern would not extract easily:
http://i37.tinypic.com/23lftd2.jpg

I'd prefer to cast it. I'm still waiting for a photo of the real
original box.
If I could get a solid block of brass that size I'd just mill it out.

"Matty F" wrote in message
...
I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!
I've not soldered brass before. Any suggestions?


why silver solder ?

"Matty F" wrote in message
...
I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!
I've not soldered brass before. Any suggestions?


If you want strength then bronze weld it, better than soldering.

On 19 Oct, 10:00, Matty F wrote:

The sample was cast.

Almost certainly gravity sand cast, by someone who knew what they're
doing, probably in greensand. Although it's even castable in an open
back mould, these were cast industrially by using a core (a separate
shaped lump of sand, laid into the mould after moulding and before
casting). If you're capable of doing cores at all, something like this
is easier to cast with an added core than it would be to use a hollow-
box pattern and to get clean pulls from the mould every time.

The big difference, in terms of pouring success, is that they'd
gravity cast it and use quite a deep mould box to do it in, with a big
pour. The inlet gate would be deep, so the pressure in the mould
cavity is high and you'd get good flow into the mould before it
chilled. Easy if you're tooled up to do deep moulds and handle the
excess material for a deep gate. Most of us though are handling small
crucibles and need every spoonful of the melt.

On Oct 21, 2:40 am, "Rick Hughes" wrote:
"Matty F" wrote in message

...

I want to make some brass boxes, about 65x45mm, with hinged lids.
I thought I'd use 2mm brass plate, and solder the bottom on with
silver solder. They need to be oil-tight!
I've not soldered brass before. Any suggestions?

If you want strength then bronze weld it, better than soldering.

Yes we seem to have all the gear for that. I'll have to learn how to
use it over the next few weeks.

I have a variety of brass bits here.
http://i35.tinypic.com/opwnlt.jpg

The box is cast and is between 3 and 5 mm thick. I have plenty of 5mm
brass plate and 0.5mm sheet (i.e. too thin), and some 2mm and 3mm
plate. The supplier has sheet in 1 metre x 2 metre sheets, i.e. rather
a lot!

On Oct 19, 3:52 am, Clint Sharp wrote:
In message
, Andy
Dingley writesOn 17 Oct, 22:29, Clint Sharp wrote:

You can even cast brass at home if you are sufficiently adventurous, I
quite fancy having a go at lost wax casting.

Brass is a pig to cast. Bronze is _so_ much easier.

I know bronze is fairly easy to work with, what are the pitfalls with
brass? I've been told it was fairly straightforward.

Apart from lost wax, the "lost frog" process is amusing...

Lost frog? OK, I'll go Google.

I wasted lots of time reading about “Who took my frog?” (by an
autistic teenager):
http://mike.whybark.com/archives/001951.html
http://lostfrog.org/