Why does my silver solder sometimes refuse to melt?
Has anyone else experienced this?
Irene in very hot Perth
Why does my silver solder sometimes refuse to melt?
I’d bet there’s something, some contaminant, grease, oil, oxide between your metal and the solder that’s keeping the heat from from moving from the metal to the solder. It could be either on the metal, or on the solder itself.
It’s not that I’m new to soldering. It’s just that sometimes I seem to have a piece of wire solder that just won’t melt.
I actually tested the solder (after I’d ruined my piece) , medium silver solder, together with a similar piece of hard solder on a piece of sterling, and the “medium” melted quite a few seconds after the hard, in fact only when the silver started melting.
I just wondered whether anyone else has had similar (horrible) experiences.
Thanks for your help, Alec.
It must be silver wire instead of silver solder.
It certainly acted like silver wire. I was helping a club member to solder, and on reflection, it could be that the solder was tarnished, as she did tell me that she hadn’t used it for ages. But would it have taken such a high temperature to melt?
Yes Irene! I experienced this a great deal in my early days of making jewellery. The reason was usually due to the metal and/or solder not being clean enough for it to flow, i.e. oxidised. Poor heat control was the main thing that plagued my efforts, such that by the time I had the area hot enough, my flux had already vaporised and the joint and solder were oxidised. The tiny pieces of solder would either not melt at all, or they would just ball up and adhere to one side of the joint. Poorly fitting joints can also be part of the problem.
A combination of things improved my soldering, and included:
Ensuring the joint was a good fit
Changing my flux from borax to Prips
Building up a good firecoat with the Prips
Better heat control
Using a solder pick to apply the solder at exactly the right time
Once I had made the above changes, I was able to solder successfully every time, including improved heat control enabling me to solder joints very close to previous joints without the previous solder flowing. It’s just good preparation and practice.
All the best with your jewellery making.
All things being normal with flux and flame, it’s not getting hot enough or
floating on flux and not contacting silver item
I have been joining metals for forty years. All kinds of metal. Copper and brass plumbing, steel in ships hulls, and silver and gold. Consistently through out the fit, cleanliness, and heat are the big factors in a successful joint.
Heat,. Too cold and nothing flows,. Too hot and the out side of the metal reaches the right temp before the interior and you get a hollow joint.
Cleanliness: Shower may melt but it won’t flow through oil or grease or hand cream. The flux won’t cover the contaminant.
The fit:. Solder sucks out loud as a filler. Capillary action will pull the melt to the tightest space.
I know this stuff because my Dad hammered it into me. The fishing boats that went to sea might have sunk with less care. And my wife would have me head if the plumbing leaked behind the sink.
All that being said,. I have to learn how to solder all over again about once a year. My Dad said he did as well. We developed a process in the way we work. Almost a ritual. Anything that changes the ritual can cause a hitch. It happens to everyone of us in greater or lesser degrees. I’m telling you it happens to me. Soldier on with the soldering. And have fun.
Hi, I recently had the same problem . I felt my hard sheet solder would not melt .
It left black spots and when i picked it they didn’t clean up .
I used soap and water and brass brushed them . tried to resolder . They would not flow .
I thought the pickle would clean it up and it didn’t (My pickle is cold not heated , but its been in there for hours.)
I now put in the pickle another piece of solder sheet and will clean it first (of tarnish) and hope this helps.
any other suggestions ? thanks
Thanks Helen. Every bit of knowledge helps!
I didn’t know about hollow, weak joints. When it comes to jewellery, one never stops learning…
I find I get hollow joints happen to me when I have too much heat on round or square wire and I am doing a butt joint. The outside temp of the wire is higher than the core and the solder doesn’'t draw to the center of the wire. It looks fine unless you bend it at that point.
I use a Prestolite torch and maybe that is why the sound of the torch is critical to me. I get used to the sound of the torch at the right heat. And it is usually the sound that gets me back to the right heat.
It’s not a new problem. I’ve suffered the same thing when I rush. What I forget to do is clean the wire with a little steel wool. If the solder has oxidized, the oxidation can actually act as a barrier to flowing. Another way to stop he oxidation is to paint the solder with marker when you first get it. You can use a different color for each solder. When the solder is heated the marker will burn off before the solder melts. I just learned that trick. Who said an old dog can’t pick up a new trick.
I think the answer might be in your statement: “it could be that the solder was tarnished, as she did tell me that she hadn’t used it for ages.”
Not only the piece but also the solder should always be thoroughly cleaned just prior to soldering. (Thus, it should not have made a difference whether it was old or not–you should clean it even if you think it is clean…:-)…)
I clean my sheet solder with a green scrubber before clipping and cut up several projects worth at a time in the three solder strengths. This works fine for me as I use up the solder before it tarnishes much. However, I had a years hiatus and when I came back to my studio the solders were unevenly tarnished. I did not think much about it until I was having hit or miss instances of the solder not melting. After about the third project I realized it was the different degrees of tarnish that was giving the sporadic results. I poured my solder chips into a plastic tea strainer and pickled them. The problem was resolved.
I’ll throw my $.02 in here on the side of cleanliness, fit and heat management as well. Solder not melting is usually confirmation of a situation I know I’ve rushed or created poorly in some way. The only thing for it is essentially starting over with the joint after slowing down and a big deep breath or two.
As Don in particular says, joining metal elegantly and efficiently is a real art that is as worthy of deepening your practice as jewelry itself. I’ve also been joining metal for 40+ years and I still feel like a beginner at least 1/2 the time. I love Don’s notion of a ritual and the sound of the torch as a temperature cue.
My suggestion is to explore the art of soldering and see where it goes, what kind of ritual develops for you. Might lead to entirely new things.
Apologies for repeating concepts that are familiar to experienced Metalsmiths.
In general, when solder just balls up and does not flow, I have found that more heat is needed. To be honest, I have not experienced flow problems with badly tarnished solder if the joint has been properly flexed and enough heat has been applied. If the piece is regular Sterling, that means the whole piece must be brought up to uniform temperature. Argentium (AS) is more forgiving of the need for heating the entire piece, as AS acts more like gold for soldering purposes.
Mention has been made of covering solder with a Sharpie. VERY useful. Do it immediately upon receipt and be sure to cover both sides of sheet solder. Use different colors for each solder type. Should you be unlucky (or clumsy) enough to spill all those little bits, different colors help with differentiation. Been there, done it, burned the T-shirt!!
Judy in Kansas, who has been busy clearing the dead vegetation from the garden and beds. Setting records of high temps here. Probably can plant a couple weeks early if this continues.
YES!..This is why I joined this group! I have been having this problem! I love all of the suggestions! Learning from the pros…that’s what it is all about! thank you!
Thanks so much everyone for your advice. I’m going to pickle that batch of solder and try it again. I like to get to the bottom of mysteries. And I like to find out why something won’t solder. There’s always a reason, and I like to tell my pupils it’s not them…
Hi, I too use green scrubbies, or folded pieces of remnant 600 grit sandpaper to clean my sheet solder before cutting chips.
usually whenever I have had solder ball up and refuse to melt, it has been due to unclean surfaces.