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Dennis
11-10-2010, 09:14 AM
Most months a new member posts a plea for help with soldering, so I thought I would summarise what they might need to know, particularly with reference to silver. Please feel free to post your add-ons and disagreements below. I must emphasise here that what jewellers do is not soldering at all, but brazing. However as they don’t seem comfortable with that, I shall stick with the time-worn usage.

Torches are sometimes listed as having a flame of a certain temperature, but that is not the whole story. It is important that the torch can provide enough heat for the job in hand. So while a small mini-torch is sufficient for soldering chains and thin rings, larger work such as heavy rings, bangles and brooches particularly in silver, will need a burner big enough to raise the temperature of the greater mass. There are many dedicated torches for jewellery, but if you decide on a hand held torch, such as the Taymar, or the GoSystem, from DIY stores the canister should say Butane/Propane mix. The size of the canister you choose will only make a difference to the available working time. For large items heat can also be conserved by making an enclosed chamber of several blocks. For silver and base metals it is not necessary to use charcoal, but some jewellers prefer it.

Strip solder comes in various grades identified by the width. Generally it is thinned by hammering or rolling to make it easier to cut and is then cleaned with emery paper or a Scotchbrite pad before clipping into small paillions. Some jewellers colour their solder with a waterproof pen to help identify any remnants later and this burns away harmlessly in use. The joint to be soldered must also be clean.
For hard or medium solder the joint is painted with borax or Auflux and paillions applied with a small brush also dipped in flux. When heated the flux tends to bubble and expand, sometimes called ‘flowering’. It then subsides, but the pallions do not return reliably and may have to be helped back with tweezers. This is less of a problem with Auflux.

Once the solder has been placed, the piece and the block on which it rests are heated in a circumspect way to allow the solder to dry out without too much displacement of the paillions. Then the heating is slowly increased, but the flame is not applied to the solder directly. Of the parts to be joined, if one is larger it is given more attention and the smaller one will heat by conduction. It is useful to work in subdued lighting to monitor the colour changes. The whole process may take 5-30 seconds according to mass of silver, but if nothing happens by then it is likely that the torch is too small , or that there is some contamination.

Solder once it has flowed and solidified will require a higher temperature to melt it a second time, so it is possible to use the same grade for 3 or 4 subsequent joints on the same piece. However as the work increases in size, it may be better to continue with medium, easy, or even extra easy solder , which require less heat. With the last two it is also wise to use Easy Flux, which becomes active at a lower temperature.
Many jewellers avoid either medium or easy silver solder as they find one or the other more difficult to use. Strangely there is no agreement on this, but I personally avoid the medium. It is a good idea not to trim or polish too close to a seam until all soldering has been completed, because polished solder joints may show as a groove when reheated. I shall not say much about paste solder which contains its own flux, because although it is very popular, particularly when working with wire, it is difficult to monitor the flow if hidden from sight, so that you might end up with an incomplete joint.

Personal tuition and the many free videos available online will clarify what no number of words can explain here. Dennis.

swageblock
15-10-2010, 09:59 PM
Re solder pallions getting dis placed by bubbling flux;Melt the pallions into balls and pick them up[whilst still molten] on a steel wire "pick".Heat the
item up to temp and apply the solder bearing pick to the join.Very accurate and controlled.

Personally I never use medium grade solder in either silver,9or18ct.

wheely
15-10-2010, 11:14 PM
Solder once it has flowed and solidified will require a higher temperature to melt it a second time.

Why is this? I've never actually understood. And why do people avoid medium?

RE paste, whilst being unable to add anything substantial about it's use (apart from it's so much easier) I love it! Would use it over pallions any day.

Joe
16-10-2010, 12:37 AM
I think perhaps that this answers itself really.

Solder isn't a simple substance. Every supplier's solder is different with great differences between one supplier's "medium" and another. The structure of hard strip solder changes when it is melt and melts at a different temperature next time - it is not a compound or homogeneous mixture; and again the time after!

I personally like paste for steel and mixed metals. But nothing beats hard solder for flowing, as a simple liquid, right through a joint. All my easy (and paste) solders have a real habit of forming liquid pools that need a poke to get them to ooze sullenly into the joint.... and the Hildebrand pastes seem to melt just as readily next time round!

Some of my pieces have over 30 solder joints - I rely on the gradual 'hardening' of hard solder to make many joins!

It's horses for courses... nothing wrong with any type of solder; but "hard" paillons are a good, general purpose, multi-use solder that are often "easy" to use! If you've just got one join to make, just take your pick!!

To be really honest - except for stainless soldering - I just grab what is nearest, which is usually the "hard" strip, already frayed into tassels and ready...

emroyjewels
16-10-2010, 07:20 AM
Dennis - excellent post, and highly likely to help some beginners.

Just one minor comment:
The whole process may take 5-30 seconds according to mass of silver, but if nothing happens by then it is likely that the torch is too small , or that there is some contamination.


This definitely depends on the size of the item - an earring or small pendant may take around 30 seconds, but if you are heating say a large bangle you'll be looking to circle with your torch for 2-3 minutes before it gets hot enough for the solder to flow. It doesn't mean your torch isn't hot enough provided you are using something like the go-system torch - just that because of the weight of the silver it needs more time to get it to a nice temperature.

Just thought I'd point this out, as a beginner might start to worry if they see nothing is happening after 30 seconds!

mizgeorge
16-10-2010, 07:43 AM
Em, if it's taking you two to three minutes to get a bangle up to temperature, your torch isn't hot enough!! I'd also say you're opening yourself up to a real firescale opportunity.

emroyjewels
16-10-2010, 08:08 AM
George I use the go system which is mega powerful, inside a handmade "kiln" and it definitely takes around 2 minutes to heat up the back of the bangle before I head round to the point where the solder starts to flow - but polishes up fine with no firescale.

Just to clarify I'm talking about a weighty bangle - 2-3mm thick wire, rather than something thinner.

Update: I just went and heated one of mine up to prove I'm not going nuts - and timed myself - 1.42 seconds before it got hot enough to where I would move around to the front.

Perhaps you should ignore my advice. Everyone has their own technique, but I would be amazed if you could solder a heavy bangle in 30 seconds flat. My technique works for me and I'm sticking to it!

swageblock
17-10-2010, 10:09 PM
Why do people avoid medium?
1;The top end of its melt range overlaps the lower end of hard grade and the low end of medium melt range overlaps the top end of easy solders .
therefore there is a good[bad]chance of melting existing joins.
2;a personal point is that I never found it to flow as cleanly as either hard or easy.I still have a strip from Johnson Matthey purchased about 30 years agoand only 10% used.
Thats giving the game away!!

Dennis
19-10-2010, 09:02 PM
Dear Emma,
I've just come back from a trip, and could not resist logging on. With anything like your bangle, the problem is not just that it is very large. It is also that it is quite thin for its size, so while you are busy heating one part, the rest is beginning to cool again. It simply does not have the mass to hold the heat you are putting in. My remedy is to use two torches to give a more even application of heat, but did not say that in my post above, to try and keep things simple. Building up a box with soldering blocks helps too, of course.
George mentioned firescale, which is another problem with prolonged heating. Some writers have a motto, 'in and out quickly', but I find that if I try to go too quickly the molten solder runs away in unpredictable directions.
Kind regards, Dennis.

wheely
19-10-2010, 09:48 PM
Why do people avoid medium?
1;The top end of its melt range overlaps the lower end of hard grade and the low end of medium melt range overlaps the top end of easy solders . therefore there is a good[bad]chance of melting existing joins

I guess I should have been able to come up with that myself. Looks so simple now :">

abyjem
01-11-2010, 06:06 PM
I am really a novice compared to most on this thread. When I first started soldering I found the paste easiest to work with because it seemed to melt so much easier and quicker and didnt jump about like paillons. However, just lately I have been leaning towards easy solid solder with borax and am finding it actually seems to work better for me. It tends to flow better, especially when soldering bezel wire onto backing plate. It just seems to draw through the joint better.

I still use the easy paste for some jobs but I dont really like the medium paste.
I've yet to try medium or hard strip solder but must do so soon.

I didnt realise just how small the paillons need to be to work well. Too thick and they dont melt properly -

Joe
01-11-2010, 07:45 PM
Ah, you should try the hard solder... soooo liquidy!

Hey, anyone up for contributing to a jewellery wiki-pedia? I'm up for doing the web stuff if you experts will do the articles...?

Kwant
12-11-2010, 09:37 AM
I have been using medium strip and easy paste for all that I do. After reading this thread I ordered some hard strip, which came today and just tried it out. It is very hard to snip but the results are excellent and in the words of Joe "soooo liquidy!" I have a feeling this will now be my solder of choice as much as possible. Thank you for this thread.

Joe
12-11-2010, 09:57 AM
On Dennis' recommendation some time ago, I bought these (http://www.cooksongold.com/Jewellery-Tools/Solder-Cutting-Pliers-prcode-999-72F#reviews). They are absolutely brilliant!

abyjem
12-11-2010, 08:25 PM
they look ideal - cutting the damn stuff is a nightmare - I lose more than half of it ! its all over the spare room floor - lol

caroleallen
13-11-2010, 07:19 AM
I use Maun side cutters to cut my solder strip. I find it dead easy - I rest my finger over the top so the pallion doesn't ping off. And I don't like medium either.

Moon Willow
27-02-2011, 09:30 PM
I know I'm a few months behind here but better late than never.

I encourage my students to put the solder strips through a rolling mill to reach a thickness of .3 mm this will enable you to cut the solder with ease and thinner solder runs more quickly.

I tend to solder everything with hard solder, when soldering joints using easy (along with easy flux powder) you might find it okay untill you try to polish, you'll find the solder gets sucked out of the joint all to easily because it is far too soft.

Carlton :cool:

Dennis
28-02-2011, 06:09 AM
Thank you Carlton,

This question comes up about once a month from new members and when I spot it, I post a link to these pages, so you will now be included. Yor cheery interventions from a professional are much appreciated. Dennis.

Moon Willow
28-02-2011, 07:51 AM
Thanks Dennis, I try to do my bit as I stumble along life's stoney path and I know how the up and coming jewellers struggle with the flame, you could write a book on it !!

Carlton

ps_bond
28-02-2011, 09:17 AM
I encourage my students to put the solder strips through a rolling mill to reach a thickness of .3 mm this will enable you to cut the solder with ease and thinner solder runs more quickly.

I'm in the same camp on that - I roll my solder fairly thin, then use snips to cut it (and it doesn't ping everywhere). Similarly, I usually stick to just hard solder - if I'm careful with the heat, I can keep just the area I'm working on at the solder melting point (although using one of the smaller nozzles for the Sievert is handy).