Cutting a channel in copper so that I can flow solder for a copper cuff

Hi, I’m a newbie and have taking a Jewelry 1 class, I want to cut a groove or channel in copper so I can flow silver solder in it , using it as an embellishment for a copper cuff, thought about etching it or using a bur (never used a bur before) or ??? All suggestions are welcome!!!
Thanks,
Oldfisher

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Hi Francis,
I’m no great expert, but it would seem to me that the best way to get an easily controlled channel is to use a file. It will take a little longer than using a burr, perhaps, but there is much less danger of going right through your sheet. Etching would certainly work, but is a lot of trouble to go to if you are only wanting one channel…if you wanted an intricate pattern, etching would be the way to go. -royjohn

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Oldfisher Hi!

Something to consider … generally speaking it’s not a great idea to mix copper (or any of the copper based alloys) with silver alloys … because when it gets wet, especially in a salty environment like sweat, a galvanic reaction occurs and the metals start to exchange electrons … I forget the direction of the transfer, but the result is the same … one erodes the other … and you end up with a mess. You can sometimes pull it off with pieces that don’t touch the skin like earrings … but if there is skin contact and the piece is worn much its gonna erode. With a cuff it might be ok if the metal contact does not get wet … especially in contact with the skin. If I were going to do such a task … I’d probably etch it with an electroetching process … I use a cupric nitrate solution, but you can get by with saltwater and a battery as long as you do it outside or with a vent hood because it produces chlorine gas. Good luck and have fun!!! Brent

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If you pour molten silver solder or silver into a copper channel you may or may not get away with it. You run a real risk of the metals alloying and blending into one another. When copper and silver are in contact they melt at a lower temperature than either one separately. The temperature at which they do that is called the eutectic point.

The way to do what you want with surer results is to engrave, or with burs cut your channel and then inlay the silver. If your design is larger or more detailed, or you choose not to engrave, then you pierce (saw) your design in a thinner piece of copper and solder that to a backing of copper. You will then have channels or cells you may fill. This is called overlay. (Look up Hopi overlay for examples.)

Either way, you make small undercuts in the channels, either after overlaying, or with your saw held on an angle when piercing. Cut fine or sterling silver to fit (fine is softer and will work more easily) and hammer that into the cut-out. You want the silver to be forced into the undercuts. That will hold it in place. Once your inlay is secure you file, sand, and polish the piece level, and the silver will look as if it flowed in perfectly.

Neil A

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How are you going to keep silver solder contained in the grove? Why not just solder a piece of silver wire to the copper and remove any solder that goes where you don’t want it to go. If you want to cut a groove, you could learn to use a graver. I am one to speak as I have yet to learn this myself. Good luck…Rob

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Separating Disc.

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Hi Oldfisher,

My guess is that you’re referring to solder inlay? If this is the case, any solder that overflows the channel you create can be filed or sanded away, then the piece can be finished.

Ball burs and gravers are a great way to create a shallow channel that is round, oval or has contours. You might consider using a separating disc to cut straight lines. Take care when using these discs as they are fragile and will fly when they break. Always wear safety glasses or a face shield.

If your sheet is heavy enough you could also try stamping patterns or words using steel stamps.

Please share photos of your finished piece.

Good luck!
Pam

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Since you are just learning, the goal is to learn new techniques. Not necessarily to last for the milenia as it probably won’t.

One easy way to chanel in copper is to bend a piece of steel wire in the shape you want, place it on the copper while it is flat, then smack it with a rubber hammer. Put your solder into the chanel with flux. Heat till it flows. Pickle, scrub, polish, bent to bracelet.

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Hello Oldfisher,
It’s been suggested that you can get the same effect by soldering silver to the copper. I agree. However, you should know that you will need to heat the copper much higher than would be necessary with silver on silver. I’ve made copper cuffs, and in order to get the metal hot enough, I make a little ‘oven’ with slabs of soldering brick to contain the heat.

In this case, you’re learning and experimenting. Give flowing the solder a try, using the ‘oven’. Also try to melt some copper - you’ll have a better idea of how much heat copper will take. All good knowledge to have.

Let us know what your experiments taught you,
Judy in Kansas, where the weather has become lovely and I’m waiting for the hummers and orioles to appear.

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It is possible to cut a channel in one metal, and then inlay another metal into the channel, but this can be a pretty advanced technique.
I did a class with Rick Eaton at GRS in Kansas Cuty, and we hand engraved channels in stainless, into which we then inlaid soft copper wire, so i know it is possible. I never continued engraving, so I never mastered this technique, but I did learn it.

The "groove " needs to be wider beneath the surface than at the surface, which is done by undercutting with a graver. Then small burrs are raised in the depth of the channel, which will help lock the soft wire in place.
The inlay wire is “punched” or hammered down into the channel, so that it spreads into the undercut sides, and around the locking burrs.

The look is very striking, but the technique does take quite a bit of practice, and some skills in hand engraving.

A somewhat similar looking effect can be achieved, applying wire to the surface by soldering it in place, which has already been suggested.

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