Soldering a 5mm bangle

[be-bops]

Hi all
I'm new to this forum and have a question
I have done a beginners Jewelry course a couple of years ago , and tried bits and bobs myself since.
On my course I made a 5mm wire silver bangle , which I am attempting to make again
When I made it the tutor did the soldering and I watched .
On my first soldering attempt yesterday I heated the bracelet for a long time with a big blow torch .
The solder wouldn't run for ages and the eventually did but not on the join . Also the bracelet seened to shrink so there was a gap in the join afterwards .
It's quits scary and also very frustrating .
Any advice would be brilliant !!
Thanks
Anna

[pearlescence]

That's what happens when a tutor does all the work - the student doesn't learn properly. (15 years lecturing in further and higher education).
It sounds like the torch was not able to get the whole bangle hot enough. Plus you need to heat the area directly away from the joint first so that the heat expansion causes the metal to close up at the joint, rather than open out, which is what may have happened here. Add in a bit of annealing as the wire heated and you have a joint opening up.
You'll need to pickle and then clean the joint by filing it to bright metal before you can try again.

[CJ57]

It would also be worth using binding wire across the bangle which would help to keep the joint together until you master it

[Patstone]

I have the same problem, had a commission for a 6mm x 3mm bangle and put two blowtorches and made a "cave" out of firebricks, and still can't get it hot enough to melt the solder. My big blowtorch with butane/propane mix has run out of gas now, but the solder I'd very thin, almost see through. Got fed up now as can't think of anything else to try.

[Goldsmith]

Something your tutor should have explained is that metal moves when it is heated, as said before the bangle will need cleaning before your next attempt at soldering. This is easier to show rather than explain, open the bangle sideways, file the solder surfaces flat, flux the surfaces, then squeeze the bangle into a tighter circle before re aligning the join. By squeezing the bangle into a tighter circle the joint surfaces should be tight together now. Gently heat the whole bangle running the torch flame circular around the whole bangle and make sure it does not open again, then attach a piece of fluxed solder across the join on the inside of the bangle, as the bangle is now warm it should stick in place OK. Now play the torch flame in a circular motion around the bangle playing the flame onto the outside of the bangle opposite where the solder is set. Bring the whole bangle up to solder flow temperature and then the final play of flame on the join opposite the solder and it should then flow through the join nicely, remember that solder will follow the heat.
I hope this all makes sense, good luck!

James

[Patstone]

It hasn't worked for me, normally use the butane/propane gas cannisters type for bigger jobs. Ran out so will get another one tomorrow, but my bullfinch one with a calor gas bottle with butane in just isn't melting the solder, not even easy solder.

What is the best for soldering silver butane, propane or a mixture. Got a calor gas bottle with butane, three cooks hand torches an a bigger propane/butane cannisters ( like the cooks torch but a lot bigger).

[be-bops]

Thank you to all for your helpful replies . I'm not sure how to bind with wire/ what sort/ how/ and how it dosen't melt so will try that another time .
I think also the reason it happened is that the join wasn't good enough . I spent a long long time trying to get it right with a file but in fact I was making it worse . In the end I cut it again and cleaned and prepared it . The soldering nearly worked after that but now my problem is that the solder didn't fill all the way round on the join . Not sure why ?
Guess I'll have to be brave and try again . Any encouraging words of wisdom out there ?
Again I have cleaned and filed it ready to go .
Thanks
Anna

[Dennis]

As James explained, metal hardens when you bend it and tends to straighten again when heated. What you were finding is that a gap opened and solder would not fill the gap.
Now that it is annealed you have a better chance, particularly if you begin to heat at a point remote from the join.


Every jeweller should have a reel of binding wire to forestall emergencies like this. It can be iron or stainless steel. It is inexpensive and will not melt. Buy one about 0.45mm in diameter and dont put the iron one in pickle, or your work will turn pink.

Here's a little box being made using it https://vimeo.com/54005915 Dennis.

[CJ57]

Thank you to all for your helpful replies . I'm not sure how to bind with wire/ what sort/ how/ and how it dosen't melt so will try that another time .
I think also the reason it happened is that the join wasn't good enough . I spent a long long time trying to get it right with a file but in fact I was making it worse . In the end I cut it again and cleaned and prepared it . The soldering nearly worked after that but now my problem is that the solder didn't fill all the way round on the join . Not sure why ?
Guess I'll have to be brave and try again . Any encouraging words of wisdom out there ?
Again I have cleaned and filed it ready to go .
Thanks
Anna

Hi Anna
This is the sort of wire I mean, it's made of steel so won't melt http://www.cooksongold.com/category_select.jsp?query=Binding+wire

Do it James's way and it should work but if you are still having problems the wire is a little bit of extra help. Cut a piece of binding wire more than twice the width of your bangle. Fold in half and put in a loop in the middle with your pliers . Wire around the bangle , if you think the joint as being south wire east to west and twist the ends. You can tension both ends if necessary but it would meanthat your joint stays together. Hope this makes sense, as James says it's easier to show than explain. It's also worth laying the joint on the pallion of solder.
Hope you manage to get it done, it's just practise I'm afraid. It's not a big job being wire, it's just a matter of spreading the heat and getting it all up to temperature

[be-bops]

Thank you I'll get some wire for next time .
But HOORAY I did it !! I can't beleive it for a newbie like me . Feeling quite proud of myself as I was very nervous .
Thank you all for your brilliant advice.
By the way , James , or anyone else , while I'm here , and for the future , how do I know when the silver temperature is up to solder melting point ?
Anna
It seems especially hard on thick 5mm wire .

[pearlescence]

When the solder melts is the glib answer. There are degrees of redness in the metal to look for, but experience is worth more than trying to describe colours in words
Well done!

[Goldsmith]

Hi Anna, when you get into making more jewellery and you have some scrap silver, it's a good idea to practice melting solder on some scrap, then you will soon get an idea of the colour of silver when it gets near to the temperature that the solder flows. Obviously each grade of solder will be different. If you are planning to make more items then some binding wire that Caroline showed would be a good addition to your tool kit. Then perhaps a bit further down the line you may like to try making soldering clamps as they can be useful securing items when soldering, check out this older posting on the forum; http://www.cooksongold.com/forum/showthread.php?t=5928

James

[Patstone]

What's your opinion about trying to heat thick silver please. Tried using four soldering blocks to make a "cave" but still couldn't get it hot enough. Some of your work must have entailed some pretty chunky metal.

[Petal]

Thank you I'll get some wire for next time .
But HOORAY I did it !! I can't beleive it for a newbie like me . Feeling quite proud of myself as I was very nervous .
Thank you all for your brilliant advice.
By the way , James , or anyone else , while I'm here , and for the future , how do I know when the silver temperature is up to solder melting point ?
Anna
It seems especially hard on thick 5mm wire .


Hi Anna,
Another trick for use when soldering is get yourself a sharpie pen, its a felt pen if you don't have that particular type, but when you make a sharpie mark on the piece you want to solder, the mark goes out once it reaches annealing temperature! So then you keep on using your torch and eventually the solder will flow. Good luck.

[Goldsmith]

What's your opinion about trying to heat thick silver please. Tried using four soldering blocks to make a "cave" but still couldn't get it hot enough. Some of your work must have entailed some pretty chunky metal.

I use an old Smiths Little Torch type oxy/propane torch Pat which gets metal very hot very quickly.

James

[Patstone]

I use an old Smiths Little Torch type oxy/propane torch Pat which gets metal very hot very quickly.

James

Would that be safe in a spare bedroom. I have a blue Calor Gas small bottle under my bench (the ones about a foot high) not sure about the capacity unless I go back upstairs again and look, but dont have the space or desire to keep big bottles in the room next to where I sleep. Need small similar to what I have now. Never used anything I have to balance i.e propane and oxygen etc. I dont normally make bangles bigger than 4mm wide, think I bit off more than i can chew this time, 6mm x 3mm thick and a mans bangle, so big around too.

[Goldsmith]

Would that be safe in a spare bedroom. I have a blue Calor Gas small bottle under my bench (the ones about a foot high) not sure about the capacity unless I go back upstairs again and look, but dont have the space or desire to keep big bottles in the room next to where I sleep. Need small similar to what I have now. Never used anything I have to balance i.e propane and oxygen etc. I dont normally make bangles bigger than 4mm wide, think I bit off more than i can chew this time, 6mm x 3mm thick and a mans bangle, so big around too.

I am not sure about any rules regarding workshops in the house, my workshop is now in a shed at the bottom of my garden. As for whether having oxygen cylinders in the house is safe, well there are plenty of people with health and breathing problems who have oxygen cylinders in the house, or if you have the funds those oxygen concentrators seem good;http://www.tuffnellglass.com/contents/en-uk/p66_oxygen_concentrator.html

[Patstone]

That looks interesting, presumably that is more concentrated than a bottle. Not sure I can justify buying that just for a hobby.
Got a new gas cylinder and I have managed to solder the bangle. Torch must have been running on empty so not so hot. Thank you for all your suggestions and help.

[TeeDee]

That looks interesting, presumably that is more concentrated than a bottle. Not sure I can justify buying that just for a hobby.
Got a new gas cylinder and I have managed to solder the bangle. Torch must have been running on empty so not so hot. Thank you for all your suggestions and help.

Hi Pat,
Portable oxygen concentrators were developed predominantly for medical use in the home and other places where cylinder oxygen was not practical or safe to use. Air is made up roughly of 79% nitrogen and 21% oxygen. A concentrator effectively scrubs the nitrogen from the air and delivers the same oxygen as you would get from a cylinder. The 2 big advantages are that it wont run out as long as you have an electrical supply and a well maintained machine and there is no stored energy in the form of a high pressure gas. With regards to safety, its very much about understanding what you are using and ensuring you assess the risks and maintain your equipment. I use both a Sievert propane only torch and a Smiths oxy/propane Little torch. Both from the same propane supply cylinder. I regularly check for leaks, I make sure pipes, joints and regulators are not damaged, I have flashback arrestors installed and have a small fire extinguisher handy. When in use I make myself aware of other combustible materials around me and if necessary remove them. E.g. my jar of argotect mixed with meths.
As James says, many people have oxygen in daily use at home. I Would be far more wary of an old butane portable fire with perished hosing and leaky joints than I would a well maintained oxy/fuel system used by a competent and disciplined operator. Oxygen in itself will not burn but it will help any other fuel be it wood, paper or a fuel gas, burn very quickly and at high temperatures. Hence its use with propane, butane, acetylene etc to achieve higher temperatures than the fuel gas on its own.
That said, Tavistock is not a million miles away from Exeter and if you are thinking of improving your soldering and possibly casting arrangements you are more than welcome to drop down here and I can take you through my system and explain some of the pros and cons of other systems.
Feel free to PM me if you want to visit or want further info on gases and I'll do my best.
I certainly don't know everything but I did a fair bit of training on medical and industrial gas installations and use during my NHS engineering career.
Hope the info helps.
Tim

[ajda]

An oxy-con performing well will typically produce around 90-95% oxygen purity at relatively low pressure - much safer than oxygen cylinders and more than adequate for a torch like the Smith. I have two large oxy-cons yoked together and two large glassworking torches, plus the Smith for silverworking, all running off the same propane tank and oxy-con setup. As Tim said, it's important to have tight joins and to check for leaks, at least with the gas - but with the oxy-cons it's not a problem to have leaky joins or excess oxygen vented around the room since the quantities and the purity of the oxygen being released are not a cause for concern.
Alan