Is it possible? Preferably using an iron rather than a torch. What flux and
solder work best.
This is for small repair work on cast-off medical equipment being salvaged
for third world countries.
All help appreciated.
Ray

There are proprietary fluxes available for stainless steel, but most people
I know use phosphoric acid. I think 50/50 solder is the go, but someone
else may have a more detailed experience than I have.
--
Regards,

Chas.

(To email me, replace "xxx" with letters tango papa golf.)

"Ray Field" wrote in message
newsV7Ol.26547$Db2.12029@edtnps83...
Is it possible? Preferably using an iron rather than a torch. What flux
and solder work best.
This is for small repair work on cast-off medical equipment being salvaged
for third world countries.
All help appreciated.
Ray

In article DV7Ol.26547$Db2.12029@edtnps83,
"Ray Field" wrote:

Is it possible? Preferably using an iron rather than a torch. What flux and
solder work best.
This is for small repair work on cast-off medical equipment being salvaged
for third world countries.
All help appreciated.
Ray

It's certainly possible. You need a good flux, and aggressive cleaning.
Most of my experience is with torch, not iron, and there's some benefit
since the torch (with a long carburizing flame) can provide some
protection against further oxidation. OTOH I guess you could set up a
nitrogen glove box if you were doing a lot of work, and that would help.
But an adequate coating of flux will work without that level of fuss.

Either an olde-fashioned zinc dichloride flux or something specific to
stainless like Eutetic Castolin 157 (if my memory is not shot, and they
still sell the same stuff decades later). Anything that works for flux
on stainless will need to be cleaned off carefully after use, as it has
to be fairly aggressive to work at all.

95-5 tin-antimony is a good choice for solder, lead free, food safe, not
as wimpy as the typical lead free plumbing solders mostly are.

--
Cats, coffee, chocolate...vices to live by

You can probably solder some small stainless steel parts with a soldering
iron, Ray, if you can get enough heat to transfer into the workpiece(s).

Harris Stay-Brite #8 silver bearing solder is a low temp (melt 430/flow
530F) solder that can be used on stainless.
The #8 formula is lead-free, tin plus 5-6% silver by weight (about $53/lb
last year, 1/16" dia)
Harris Stay-Clean liquid flux (zinc chloride/hydrochloric acid) will work on
most metals, including stainless, except it's not recommended for aluminum
(or electrical/electronic applications).

You probably realize that typically, stainless alloys don't conduct heat
very well, and soft solders generally aren't exceptionally strong. I suppose
that there would be some strength information on the Harris website.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Ray Field" wrote in message
newsV7Ol.26547$Db2.12029@edtnps83...
Is it possible? Preferably using an iron rather than a torch. What flux
and solder work best.
This is for small repair work on cast-off medical equipment being salvaged
for third world countries.
All help appreciated.
Ray

On Tue, 12 May 2009 07:42:04 -0400, "Wild_Bill"
wrote:

You can probably solder some small stainless steel parts with a soldering
iron, Ray, if you can get enough heat to transfer into the workpiece(s).

Harris Stay-Brite #8 silver bearing solder is a low temp (melt 430/flow
530F) solder that can be used on stainless.
The #8 formula is lead-free, tin plus 5-6% silver by weight (about $53/lb
last year, 1/16" dia)
Harris Stay-Clean liquid flux (zinc chloride/hydrochloric acid) will work on
most metals, including stainless, except it's not recommended for aluminum
(or electrical/electronic applications).

You probably realize that typically, stainless alloys don't conduct heat
very well, and soft solders generally aren't exceptionally strong. I suppose
that there would be some strength information on the Harris website.

Staybrite is considerably stronger than ordinary lead-tin solder, and
it wets stainless like magic. There is
Staybrite and Staybrite 8. Regular Staybrite is very fluid while
Staybrite 8 has a "mushy" zone and can build up a bit of filet.

Strength is about 14000 PSI tensile, 10000 PSI shear, or about 5x the
strength of ordinary lead-tin soft solder.

"Chas" wrote in :

There are proprietary fluxes available for stainless steel, but most
people I know use phosphoric acid. I think 50/50 solder is the go,
but someone else may have a more detailed experience than I have.

I've used regular tin/lead electronics solder on stainless steel RF
connectors. We used a special stainless steel flux, but I don't recall the
brand. It was watery, and spit a lot when hit with the iron. The
resulting splashes rusted every bit of plain steel they hit, and the whole
process tended to eat soldering iron tips fairly rapidly.

Doug White

On May 12, 4:49*pm, Doug White wrote:
"Chas" wrote :

There are proprietary fluxes available for stainless steel, but most
people I know use phosphoric acid. *I think 50/50 solder is the go,
but someone else may have a more detailed experience than I have.

I've used regular tin/lead electronics solder on stainless steel RF
connectors. *We used a special stainless steel flux, but I don't recall the
brand. *It was watery, and spit a lot when hit with the iron. *The
resulting splashes rusted every bit of plain steel they hit, and the whole
process tended to eat soldering iron tips fairly rapidly.

All nickel alloys (including stainless steel) need an acid flux.
Once tinned, you can reflow the solder with milder fluxes
to join to other parts.

"Wild_Bill" wrote in message
...
You can probably solder some small stainless steel parts with a soldering
iron, Ray, if you can get enough heat to transfer into the workpiece(s).

Harris Stay-Brite #8 silver bearing solder is a low temp (melt 430/flow
530F) solder that can be used on stainless.
The #8 formula is lead-free, tin plus 5-6% silver by weight (about $53/lb
last year, 1/16" dia)
Harris Stay-Clean liquid flux (zinc chloride/hydrochloric acid) will work
on most metals, including stainless, except it's not recommended for
aluminum (or electrical/electronic applications).

You probably realize that typically, stainless alloys don't conduct heat
very well, and soft solders generally aren't exceptionally strong. I
suppose that there would be some strength information on the Harris
website.

--
WB
.........
metalworking projects
www.kwagmire.com/metal_proj.html


"Ray Field" wrote in message
newsV7Ol.26547$Db2.12029@edtnps83...
Is it possible? Preferably using an iron rather than a torch. What flux
and solder work best.
This is for small repair work on cast-off medical equipment being
salvaged for third world countries.
All help appreciated.
Ray



Way back when I serviced restaurant equipment, I used Staybright on
stainless. It was strong enough, and food safe.


Steve R.

Thanks for including the relative strength comparison, Don. That puts the
strength of the StayBrite products into better perspective.

I had checked Harris's specifications for #8, but didn't follow up by
checking any strength specs for typical 60/40 alloys.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Don Foreman" wrote in message
...

Staybrite is considerably stronger than ordinary lead-tin solder, and
it wets stainless like magic. There is
Staybrite and Staybrite 8. Regular Staybrite is very fluid while
Staybrite 8 has a "mushy" zone and can build up a bit of filet.

Strength is about 14000 PSI tensile, 10000 PSI shear, or about 5x the
strength of ordinary lead-tin soft solder.