rusty steel wire...handy when silver soldering

....Currently rolling and silver soldering brass clock spring barrels. I found that I had run out of clean steel wire for twisting around the barrel to close up the join ready for silver soldering, and used some wire that was passed to me...it is already coated with rust....but not enough to prevent the use of the wire.

....Once the soldering is over there was no wire to remove from the outside of the joint because the rust effectively resists the flux/solder! So, lightly rusted steel wire will now be my main stay for securing joints and joins prior to silver soldering.

Bob,

Assuming that it's strong enough to hold what you are soldering: Soft Iron wire [as used by Florists] is ideal, for the very reasons you have found.

MichaelG.

That green garden wire is useful for emergency repairs in all sorts of strange situations, I kept a roll of it in my car because it has a million uses

One day my old Nissan Bluebird rear suspension arm broke about a mile from home.

After the initial shock I jacked up the car, took about 15-20 turns around the affected area and bound it up along the length of this "new strut" then limped slowly home with my flashers on

**LINK**

Isn't it just about the only application left for near-pure iron, as it doesn't work harden easily?

Neil

Thanks for the tip.

Practical advice on a silver soldering problem would be much appreciated.

Have had 100% success with silver soldering small items where the whole item can be heated to the correct temp.

I am trying to make a box to replace the bottom tank on a 1929 morgan three wheeler, 18" x 4" x 3" deep in .8mm brass with the folded tabs at the corners being silver soldered, prior to soft soldering vertical tubes to it.

What is the correct procedure to avoid or deal with distortion caused by differential expansion?

David

David,...interesting post!

The way I managed a similar job was to place the folded and fluxed workpiece across my charcoal forge and preheat. the forge was/is slightly smaller than the workpiece but can still heat up the work to a high temp. Then use a gas torch to locally heat the joints the final way to melting temp for the silver solder......

WARNING...this will only work with a very clean medium such as good quality charcoal as there are few impurities....a coke forge will just contaminate the work and the solder will not run and fuse properly. Also, avoid the barb-a que charcoal with ignition agent added for the same reasons.

Bob

thanks for the advice, I'll give it a try.

David

A gas barb-a-que should do the job, one with a steel plate on top is best , also good for heating a ring gear, before putting it on the flywheel.

Ian S C

Brass expands more than steel. When joining materials with differing coefficients of expansion consider two things.

The required joint gap should be at the brazing, not room, temperature.

When the joint cools, the joint is put under compressive stress not tensile. The solder is, in effect, being squeezed. If possible make the female element of joint steel

Not possible?

Use a larger joint gap than usual. The extra volume of alloy will help to accommodate the thermal stress.

Cool slowly.

Re soft iron wire. Fluxes remove oxides (rust). Keep the two apart or you will add a new feature to your assembly!

For more detailed info go to **LINK**

Keith

hi bob,

can i make a couple of suggestions?

use thermalite blocks as a brazing hearth instead of charcoal. they can be obtained from any builders merchants very cheaply.

i would not want to make a clock barrel other than out of proper thick gauge brass tube. much quicker and easier plus you do not end up with something that is annealed.

cheers,

julian

some interesting stuff turning up in this thread!.......

A couple of points;.........I already DO use a hearth (made from firebricks that are very cheaply purchased from the Wilkinson supermarket chain) but the Thermalite blocks source is a good one as they are very light weight which can be useful. The reference to my charcoal forge is purely to preheat larger items up to near soldering/brazing temp...I have found that a really clean heat source is vital or silver solder will fail for sure!

The clock spring barrels that I made this last week are 1/8 inch wall thickness,..are annealed first (from scrap sheet) then rolled by hand around a former, accurately jointed, and silver soldered.......the rolling and any subsequent manipulation tends to work harden the resulting barrel....so they are not used in a soft state. I have been making barrels like this for some years and these were made in the workshop of Epping Forest Horology Club with much interest....i videoed the process and once I have done some basic editing will post the vid either here or on youtube.

I have found the rusty wire to work well, flux or not!.......previously there was always some steel wire to remove from the join......Keep the comments coming as it's all good!

Edited By Bob Stevenson on 28/02/2016 21:34:30

hi bob,

thick gauge brass tube is easily obtainable for clock barrels.

it isnt that expensive.

i really cannot think of any reason why you should resort to rolling and silver soldering 1/8" thick brass to make them.

clock making is not easy, and there is no reason to make it harder than it already is.

cheers,

julian

Hmmmmmn........... I was quoted £97 plus VAT for half a metre for thinner wall tube than this!

hi bob,

i have lots of thick gauge brass tube for barrels in stock for possible future projects. if you let me know what you want i might be able to sort something out with you.

i think you ought to look around re suppliers. perhaps other forum members can come up with suggestions. mine is all Clerkenwell stuff many years ago.

these days, M-Machine metals at Darlington are very good. they have lots of stuff not on their website.

cheers,

julian

Edited By julian atkins on 28/02/2016 23:50:08