Solder won’t flow on ring repair

[avarogers]

Hi guys!

Recently a friend asked if I would be able to repair their “sterling silver” ring. The back split and it seemed like a simple solder repair down the back (where the ring hits the back of the finger). I don’t understand why, but for some reason the solder won’t flow at all. I’ve tried soft medium and hard silver solder, the seam is perfectly matched up there’s no gap and I’ve tried different torch tips for more and less heat, and theres no change.
Does anyone have any suggestions as to why this may be the case? I’ve never run into this problem before and don’t know where to go from here.

Any insight would be greatly appreciated!

Ava

[islandmaples]

Dirt and grease in the crack possibly?

[Judy_in_Kansas]

Hello Ava
When the solder balls up and just sits there, I first increase the heat. Also add flux to the joint ( Battern’s flux is my fav.) while the metal is still hot.

Gotta be alert to slumping or those indicators that melting is incipient!!

You’ve already made sure that the joint is clean and fits. Unless this is some mystery metal, I’m puzzled.

Hang in there. Judy in Kansas where today was just lovely. Hope it holds through tomorrow and the football game.

[kreder9277]

Is it possible the ring is aluminum? Solder won’t stick to aluminum.

[avarogers]

You guys are great thank you!
I was guessing it could be a different metal. Are there any ways to tell if it is aluminum or not?

[DonMeixner]

I don’t know how to test for aluminum. If it is a simple band and you have another that you know is silver you could compare weights. That’s the limit of my thinking this morning.

Don

[tonykonrath]

Aluminum would have melted long before the solder balled up.

[kreder9277]

Hope this isn’t to complicated but this is what you could do.

Is this Silver, aluminum, stainlless steel, zinc or whatever.

First we find the area of the wire which is Pi x radius squared = area Pi = 3.14

Diameter of the wire is .080 inches

So the radius is .040 inches. 3.14 x .040 x .040 = pi x radius x radius = .005 square inches

Now multiply the area x the length of the wire to give you the volume of the wire. area x length = volume

The length of your wire is the circumference of the ring circle which is 2 x Pi x radius = circumference

The diameter is .700 so the radius is .350

So 2 x 3.14 x .350 = 2.198 inches = the length of your wire

Length x area - volume So, 2.198 x .005 = .011 cubic inches

The density of fine silver is 6.064 ounces per cubic inch

Density x volume = weight So, 6.064 x .011 = .067 ounces

So lets weigh my ring

So I get .0625 ounces for my weight but I calculated .067 ounces Why is it off.
Answer. My ring is not pure silver which has a density of 6.064 ounces per cubic inch
My ring is sterling silver which is .925 silver composition.
So, I take my answer of .067 ounces and multiply it by .925 = .062 which is close enough because I estimated on the diameter of the ring to get my length.

[kreder9277]

The density of aluminum is 1.56 oz/per cubic inch, stainless steel is 4.64 oz/per cubic inch, nickel is 5.15 oz/ per cubic inch, zinc is 4.12 oz/per cubic inch. The same formula can be used with these different densities to determine your material.

[halstead1]

What’s your soldering setup look like? Are you using 3rd hands? It could be drawing the heat away if you are…

[miketayse]

I’ve occasionally had trouble like this. I recently could not get solder to flow properly on an old, “stamped sterling” boy scout ring. I had recently moved to another location and not fully set up my studio. I took me awhile to figure out what I needed to do, or had on my bench in my previous location. I had not set up a charcoal block because I had not fully finished up my exhaust fan. Charcoal blocks create a small oxygen reducing atmosphere for soldering and it worked great on the problematic ring. It took me awhile and created much frustration before I put the solution together. I felt like a idiot, because I’ve used this solution before! For what it’s worth, I use Oxy/acetylene for a quick solder when sizing rings. In this particular instance, for me I had the ring buried in some sort of heat gel, because of some colored stones and move and heated quick. When I teach, I have students put solder on top of the joint, and set the ring on a screen and tripod and heat from below, so they see heat draw the solder into the joint.

[avarogers]

It’s all strange. I tested the metal with an acid test and it turned a form of red, so I assume it’s silver. I pickled the piece and cleaned it and it still wouldn’t flow at all the metal wouldn’t even turn red hot, like it usually does. I’ve never experienced something that wouldn’t flow like this before. Thank you guys for all your help and brainstorming I really appreciate all your time

Ava

[avarogers]

I didn’t use a third hand but good thinking!

[avarogers]

Here are some photos of the ring!

[islandmaples]

Try running a fine saw blade through the crack and then solder

[Brucesprucely]

Are you putting the stones in water? If that’s the case you just need to add more heat. It never ceases to amaze me the amount of heat sterling will sync away from the joint. With a ring as wide as that I would seriously crank the heat. Clean the ring, clean the joint, apply flux and really take the heat to it.

[Philthrelder1]

Aluminum melts at a lower temperature than solder. You should be able tell by just picking it up. The shank would have melted long before the solder.
Make sure that the joint is tight and well fluxed. I prefer paste flux. Sounds like you’re using a screaming hot oxidizing flame. Use a bigger tip, get to a reducing flame and then add oxygen for a hotter but not oxidizing flame. Good luck.