The Donut

Ok. . . Here is a beginning level note of discussion.

Imagine a flat copper donut. You want to solder a flat silver donut hole
into the center. You have a fairly good fit, you flux, you put your solder
chips around the seam, you torch it. The gosh darn thing simply will not
bridge the seam at cerain areas and you eventually scorch the donut hole into
unwanted reticulation.

How can I marry the hole to the donut perfectly?

Imagine a flat copper donut. You want to solder a flat silver donut hole
into the center. You have a fairly good fit, you flux, you put your solder
chips around the seam, you torch it. The gosh darn thing simply will not
bridge the seam at cerain areas and you eventually scorch the donut hole into
unwanted reticulation. How can I marry the hole to the donut perfectly?

It appears the issue is that the copper and silver expand at different
rates and the outer copper one (because of its shape) expands leaving your
gap.

You could try having a slighlty bigger silver disc than will fit the hole,
when the copper expands it will drop in the hole and then solder it. How
much bigger? Some, not too much. (You could of course heat the donut and
measure how much bigger the hole is when it is hot)

you could try pumping most of heat into the silver disc so it expands first
(postential soldering problems with this route-ideal is everything going up
intemperature evenly).

Whatever you do use a ton of white paste flux. You need a long working time
with this one and that flux will give you enough. If your flux begins to
turn green put some more flux on. If the flux is brown you will have to
start over. Do not pickle as a pickled finish interferes with effective
solder flow (seams need to be scraped or cleaned prior to soldering) You
can’t have too much fluw when working with copper (and sterling for that
matter), golds are fine with a thinner flux like Batterns or Pripps.

Tell us what worked-should hear some more from the list on this one.

Charles

Brain Press
Box 1624, Ste M
Calgary, Alberta, T2P 2L7
Canada

tel: 403-263-3955
fax: 403-283-9053
Email: @Charles_Lewton-Brain

Okay, here’s my 2 cents worth…

Two points;

Once the solder stops flowing properly, pickle the piece to remove the
copper oxides, then reflux and continue soldering.

If I were to do this job, I’d get as perfect a fit as possible, one in
which I’d have to force the center into the outside piece. It should be
almost seamless. I’d use a silver brazing flux. I think the trick here
is getting a near perfect fit. My personal technique (for what it’s
worth…) is I flow the solder from only one point because I like to
have almost no clean-up after the soldering.

Xalkn@aol.com wrote:

Ok. . . Here is a beginning level note of discussion.

Imagine a flat copper donut. You want to solder a flat silver donut hole
into the center. You have a fairly good fit, you flux, you put your solder
chips around the seam, you torch it. The gosh darn thing simply will not
bridge the seam at cerain areas and you eventually scorch the donut hole into
unwanted reticulation.

How can I marry the hole to the donut perfectly?

         Jeffrey Everett

Handmade 18K, 22K, and platinum gemstone fine jewelry.
Diamond setting, rubber/metal molds, casting, lapidary
Die and mold engraving, plastic patterns for casting.
Cad jewelry design, cad/cam milling scroll filigree…
P O Box 2057 Fairfield IA 52556 515-469-6250

WELL! First is this to be a Jewish, Protestant, or otherwise Wedding???..

Sorry, its late, Win '95 is Sh___ and I’m punchy . .

Jim

At 09:01 PM 10/22/96 -0400, you wrote:

At 12:06 AM 10/24/96 -0400, you wrote:

WELL! First is this to be a Jewish, Protestant, or otherwise Wedding???..

Jim

At 09:01 PM 10/22/96 -0400, you wrote:

Ok. . . Here is a beginning level note of discussion.

Imagine a flat copper donut. You want to solder a flat silver donut hole
into the center.

How can I marry the hole to the donut perfectly?

If it’s Episcopal, give me a call…Fr. Mark

Jim Chambers wrote:

WELL! First is this to be a Jewish, Protestant, or otherwise Wedding???..

Sorry, its late, Win '95 is Sh___ and I’m punchy . .

Jim

At 09:01 PM 10/22/96 -0400, you wrote:

Ok. . . Here is a beginning level note of discussion.

Imagine a flat copper donut. You want to solder a flat silver donut hole
into the center. You have a fairly good fit, you flux, you put your solder
chips around the seam, you torch it. The gosh darn thing simply will not
bridge the seam at cerain areas and you eventually scorch the donut hole into
unwanted reticulation.

How can I marry the hole to the donut perfectly?

orchid@ganoksin.com

orchid@ganoksin.com

If you cant get the PROPER FIT then Pickel the article, wire brush, so it is super Clean, Then use the hardest flowing solder you have. It also helps to add solder with a pick so the solder doesnt get
dirty on the other side of the article. If You would have had a good
fit, you would not have all these problems, Taking your time at the
beginning saves it in the end
Steven