Large pieces soldering difficulties

Hi, I’ve been having trouble getting even easy 18kt gold solder to
flow on large pieces such as pendants and rings. I’ve been
soldering for over twenty years and on sterling and more delicate
gold pieces with no problem. On these larger pieces the gold looks
ready to melt and the solder doesn’t flow.easily, no matter how
clean, well fitted ,or fluxed. Has anyone else experienced this
problem and can offer any tips.

Awaiting response
Susan

    Hi, I've been having trouble getting even easy 18kt gold
solder to flow on  large pieces such as pendants and rings. 

Hi Susan;

I can’t say with certainty what the problem is without seeing the
particulars of the situation, but let me offer a few facts and tips.
First, 18K is a much better conductor of heat than 14K, so like
silver, volume of heat is a concern as you have to pour more heat
into the piece itself to compensate for conduction and radiation of
heat away from the solder joint. This will likely have you heating
the piece longer, which means you are expending the ability of your
flux to continue to do it’s job. Try cutting the solder into much
smaller chips and placing more of them. I might even advise using
paste flux (Handy of Dandix) instead of self-pickling battern’s
types. Use a bigger torch tip and bathe the article in a preheating
strategy before coming in on the solder joint. And 18K usually has
proportionately more copper in the alloy which means you are likely
to have it actually oxidize easier than 14K. Sterling will be
similar, except that the flow point of sterling solder is much lower
than the melting point of the sterling compared to the difference
between 18K solders and 18K alloys. Good luck, I’m sure others will
offer more help on this.

David L. Huffman

Susan, David/s advise seems very sound and will probably solve your
problems. One more thing to look it however…I find 18K solder
ain’t the same from everyone. I have found 18K hard solders
especially can vary greatly in their flow temp and you must really
practice tight torch/heat control. If your problems continue after
trying David’s suggestions, try another source of solder and maybe
even drop down to medium or easy solder depending on the gauge of
material your using.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2

Hi Susan, Solder temperature can vary greatly, from silver to gold.
I found that Rio’s hard solder barely flows at all. Hauser and
Miller has the most even flowing solders, but they tend to color.
Hoover and Strong has the highest melting timp solder, but has the
best color. CH Haffner, Germany, solders flow the best for bezels,
and fabrication which takes many solders.

For all around use, I would go with Hauser and Miller.

-k
Karen Christians
M E T A L W E R X
50 Guinan St.
Waltham, MA 02451
Ph: 781/891-3854
Fx: 781/891-3857
www.metalwerx.com
email: @Karen_Christians

believe it or not the flux has a lot to do with solder flow. Some
solders flow well with pripps. some with Magic flux, others with
batterns and is all else fails paste flux! A little trouble some to
deal with but probably overall the best for silver. Ringman