Yes, i recall 
my hubby just gave me his propane tanks heās not using. Iām going to try with that. I donāt have a master jeweler that I can go to watch him/her solder as you mentioned. 
Hi Janet
In your last post you mentioned "Every time you heat the piece, the solder diffuses a bit more in the previous seams and thus raises the melting point of those older seams."
It has been my understanding that the reason the melting point of older solder seams rises after each soldering is that the zinc is vaporizing out of the solder each time you heat it and less zinc results in a higher melting point.
Unfortunately I do not have a reference to back this up, but it has always made sense to me.
Your thoughts on this??
Regards
Milt
Kilt, some zinc is vaporized, especially if the solder is overheated. But as the solder is heated and flowed, any temperature above itās melting point means a solder can melt and flow that has less copper and zinc, and the existing pool of solder can this dissolve some of the silver around it, meanwhile, some of the copper and zinc can diffuse into the parent metal short if actually melting it. So there are three, at least, mechanisms. The solder picks up parent metal and melts it, creating a higher melting point solder. And some solder components diffuse into the parent metal, leaving behind higher melting solder. And yes, some zinc may vaporize, doing the same.Peter Rowe
Hello Rachael,
Iām not sure what you mean by ādensityā, but the weight of AS is the same as regular Sterling - AS is Sterling plus a tiny bit of germanium. The AS alloy contains 93.5% silver, as compared to regular Sterling with 92.5% silver. That probably makes AS very slightly heavier than standard Sterling, but unless you can measure micrograms, you canāt tell any difference.
So far as avoiding fire scale on Sterling, I do use Pripās flux, which has been discussed already. Batternās flux is my choice for fluxing the joint. It takes such a little Batternās to do the job that I use an insulin syringe to place the liquid on the joint, heat a bit to dry, and solder.
Still, I think the best way to avoid fire scale is to use one of the alloys (AS, Continuum, Sterlium, etc.) that does not fire scale. I encourage you to read up on them and then get some to use. So far as soldering AS, it does fuse very nicely. That means, no solder. Fusing is a skill, and I can fuse wire well, but have not been successful fusing larger pieces like bezel to sheet. AS solder is very useful for those joints! BTW, the solder comes as sheet, so you can cut pallions of any size you want. If you get two grades of solder, do take the time to cover both sides of the sheet with different colors using magic marker before you cut it up. That way you can distinguish one solder from the other. VERY handy should you ever spill some.
Probably more than you wanted to know,
Judy in Kansas
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I see a few answers containing the recipe for Prippās flux. I find it easier to purchase it from Contenti. It is fairly inexpensive and works as both a firescale preventative and flux. Use in the same manner as described for the homemade flux. Warm piece, spray until white coating is even. I place my solder at this point. Heat, join, breathe!
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Hi Janet
In your last post you mentioned āEvery time you heat the piece, the solder diffuses a bit more in the previous seams and thus raises the melting point of those older seams.ā
It has been my understanding that the reason the melting point of older solder seams rises after each soldering is that the zinc is vaporizing out of the solder each time you heat it and less zinc results in a higher melting point.
Unfortunately I do not have a reference to back this up, but it has always made sense to me.
Your thoughts on this??
Regards
Milt
-
Not all solders have zinc.
-
You can think of increased diffusion around the join as (in effect) āadding more silverā to the alloy in the area of the join, thus raising its melting point. In the case of gold, itās adding more gold.
Janet in Jerusalem
Kawaiidragon15h janetb
Yes, i recallmy hubby just gave me his propane tanks heās not using. Iām going to try with that. I donāt have a master jeweler that I can go to watch him/her solder as you mentioned.
Must be lots on the internet. Not quite the same, but it could definitely help. Try to find someone doing a complicated piece.
Janet in Jerusalem
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Like a 1/2 cup of powdered boric acid and 1/2 cup denatured alcohol?
Instead of using Borax, I would suggest switching to Boric Acid H3BO3. Borax does not have the same kind of action to prevent fire or reduce fire scale. Boric acid forms a molten layer that blocks oxygen from coming into contact with the surface but Borax doesnāt really do that.
For brazing/soldering silver, I use the paste from Lowes plumbing as a flux. The Boric Acid and denatured alcohol is not so much flux as it is a āsafety polishā, protective layer. You can get boric acid at more drug stores, the flux and denatured alcohol from Lowes.
Cheers,
Tyler
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Janet and Peter
Thanks for your clarifications on how solder temperatures increase with each heating
MIlt
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Tyler, you have it backwards.
That is why borax is used as a flux
when casting.
Boric acid burns off at a lower
temperature when soldering, it is used
to protect areas from oxidizing, while borax is
used on the seam where you are soldering
to keep the metal free from oxides.
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Hey Richard,
You may want to read my response again. Like you, I also suggested using Boric acid was a safety polish (part coating to prevent fire scale). I use a flux from Lowes hardware that is common for brazing plumbing copper with silver solder. Thatās what I remember typing. Maybe I didnāt save it after typingā¦
I use borax in addition with my soap for my laundry. You may like it for flux and thatās cool. I just prefer the paste that I use from Lowes. The important part to that is that I do not like the green liquid flux. I canāt even remember the name itās been so long.
Cheers,
Tyler
Tyler
Educational, not argumentativeā¦
āInstead of using Borax, I would suggest
switching to Boric Acid H3BO3. Borax does
not have the same kind of action to prevent
fire or reduce fire scale. Boric acid forms a
molten layer that blocks oxygen from coming
into contact with the surface but Borax
doesnāt really do that.ā
My understanding is that boric acid
burns off at a lower temperature than borax.
I use white welding paste flux for
soldering (brazing) prevents fire scale in
combination with not getting metal any
hotter than what is needed to get
solder to flow, and careful annealing.
I have used Magic Flame Soldering Compound for many years now and really like it. As with every dip you need to use between each application of heat. Magic CastĀ® Magic FlameĀ® 16 oz. Concentrated Soldering Compound | Stuller
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I was taught to use hard solder on the earliest soldered areas, then medium, and possibly even easy solder at the last. So I would solder a ring together with hard as well as the bezel or gallery wire that would encase the cabochon. I would then attach the bezel to the backplate with medium. I would solder that to the ring band with easy solder. I have since learned better control of my torch/flame and I can use all hard or medium for any job.
I am not so sure that while we are having all of this discussion about solder and flux, the real problem could possibly be your technique as a newbie. Since you donāt have anyone in your area to learn from, I suggest the you look online for some video tutorials on soldering technique for jewelers. There are so many really fabulous professionals that post video tutorials for free. There are also lots of books. I learned almost everything this way. I hope you will check it out.
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Since switching to a professional grade flux and firescale preventative, instead of using borax and water, Iāve had very little issues with my solder Iāve also added argentium solder to my arsenal and a propane torch and things run much smoother. Iām so appreciative for all the amazing advice Iāve received from everyone here. Thank you all so much!
Small thing, you can get Boracic acid (this is not Borax that is found as ?20mule team in clothes washing) Boracic Acid 99% is Roach powder found at Walmart, Lowes etc.
I pass most of my work through a boric acid and alcohol wash and burn off the alcohol before soldering and annealing, especially if I have already done any polishing. This almost completely eliminates firescale and makes soldering joints a lot easier than just handi flux. I keep the solution in a small canning jar sealed with a spring clip. Some of my bigger pieces donāt fit into the jar and I have to paint the solution on. This is messy and I waste a lot of it. Any ideas on larger containers that will stay sealed when not in use. I am thinking a glass dish with a ground top seal, but I canāt find one. Any suggestions are appreciatedā¦Rob
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Tupperware. Or a glass baking/storage dish with a snap on plastic lid. There must be a glass lasagna pan that has a snap on lid for transporting to the pot luck dinner.
Possibly something similar to one of these: