needed, good silver solder flux / guidance

[55fossil]

    Well, back to the old problem of I cannot get my solder to flow unless I use a blow torch. Most of my pieces use 24 gauge sheet and fancy bezel. I can get everything red hot and the damn solder still just sits there. Nice tiny little squares of easy solder. The flux burns off, the silver starts turning black and the solder still just sits there.

Help....  Any input on a good solder flux for sterling silver and tips on how to do it right.
?  Do you pickle your silver before soldering?
? Do you put flux on everything and ..... 

[ileney]

    Well, back to the old problem of I cannot get my solder to flow unless I use a blow torch. Most of my pieces use 24 gauge sheet and fancy bezel. I can get everything red hot and the damn solder still just sits there. Nice tiny little squares of easy solder. The flux burns off, the silver starts turning black and the solder still just sits there.

Help....  Any input on a good solder flux for sterling silver and tips on how to do it right.
?  Do you pickle your silver before soldering?
? Do you put flux on everything and ..... 

These are some reasons why solder might not flow:
1)Solder won't flow if your join isn't clean, so make sure it is clean even if you have to brass brush with soap and/or pickle the piece first.
2) Make sure your solder is also clean and that you fluxed your solder (a bigger issue with Pripps or similar as opposed to a paste solder IMO.) You may find paste solder easier at first than Pripps or other thin types that require you to heat a little before applying.
3) Make sure the join is really tight. Solder won't fill gaps.
4) Make sure you evenly heat the entire piece and then, when it starts to get hot, both sides of the join evenly. Use the tip of the blue flame, hottest part. If you aren't sure you are heating all parts evenly, you can take a sharpie magic marker and draw a line around the entire bezel, then see if it disappears from all of the bezel at the same time or if it takes longer for part, meaning you aren't heating it evenly. When the sharpie disappears, you are at annealing temp., not soldering temp.
5) Make sure you fluxed the area to be joined, or the entire thing (doesn't matter if it is just the join except that fluxing the entire thing may lessen fire scale.)
Most flux bubbles, turns white, then clear and runny when it is ready to go.
6) If all else fails, consider that what you think is solder may actually just be really thin silver that got mixed into your solder jar (yes, I learned this can happen the hard way. The funny thing is that I had stubbornly kept at it so long and tried so many times that I formed a layer of fine silver that eventually fused the bezel! I only realized afterwards what had gone wrong when I realized there was a balled up piece of silver attached under the seam!)

Good luck!

[betc]

What ileney said, but a few more thoughts.

What kind of torch are you trying to use (other than the blow torch)? And does it work with the blow torch?
What kind of flux are you using? I can't imagine it not bubbling if it's any of the standard jeweler's fluxes (Handy, Pripp's, Rio, cupronil...)
Have you considered trying to heat from below if you're having trouble heating from above? You can place a screen over an opening between two blocks and try from underneath. Still, make sure your torch keeps moving.
Make sure that the solder stays right next to the join...24gauge sheet is not very thick and can tend to distort under heat which could make the solder roll away from the join.

Good luck from me too.

[Debbie K]

The biggest reason I've have for soldering not flowing is tarnished solder. I keep all my solder in zip lock bags and don't cut more than I'm likely to need for the job. If it looks tarnished, I sand it down on both sides. Steel wool has oil in it which may interfere with the solder flowing so I don't use it.

Another possible cause is not getting the metal and solder hot enough quick enough. I use my torch on low to dry my flux and once it glasses over I turn the heat up. Just don't do like I did today; keep the torch moving so you don't melt delicate things!

I use paste flux and either a Bernzomatic propane or mapp torch or an Orca propane oxygen assist torch.

In rereading your post, you said that your silver turns black. If that's true, the flux isn't working. Your silver where it has been fluxed should remain silver colored. I think you may have a flux problem.

Debbie K

[milto]

Mix boric acid (roach powder) and denatured alcohol and dip or paint this on your sterling , light it, but your bezel on add flux and solder, heat finished.
the boric/alcohol serves 2 purposes, first cleans your sterling, secondly helps eliminating fire scoff. As far as  solder being dirty etc, some of the solder I use is from the'70's and is basically black.

Good luck and keep at it.