“Excuse me, could you take a look at my infected toe… or my enlarged goiter.” These are the types of questions I assume I would get if I told someone I was a doctor. (I am not by the way)
Well, over time as a jeweler, you are going to be faced with the task of sizing a ring, either as a customer repair, or when your friends and family find out that you work with jewelry, and they will have certain projects you can’t say “No” to.
Sizing a ring down is intimidating enough as a beginning jeweler, but once you do it a few times, you realize it isn’t as hard as you once thought. Making a ring larger in size is a bit more scary, because you are actually adding a piece of shank, rather that cutting a piece out and soldering it back together.
Today I am going to try to alleviate your fears and walk you through the process of sizing a ring up by adding material to a ring. Hopefully, if you have never tried this, and turned projects away, this project will give you a bit of encouragement and courage to tackle this task…… and there is a FREE Downloadable Quick Guide at the end.
Ring Sizing Tutorial with Free Downloadable Quick Guide
The first thing I do before soldering on any jewelry is give it a good cleaning, either with an Ultrasonic Cleaner, or with an old tooth brush and hot soapy water. Most jewelry gathers all kinds of “gunk” in the underside, from lotions and perfumes, to food and dead skin. Yuck, I know, but this makes for some uncomfortable smells when heated.
In this example. I have chosen a gold ring with diamonds to demonstrate the task. This ring needs to be increased by 2 sizes. If you are unaware of the history of the ring, I would suggest checking to see if there are already solder joints in the shank. I do this by slowly heating the shank and looking for any discoloring lines in the shank. If you see this, it is a good sign that it has been sized before. This line is a good place to cut the ring. If there are no preexisting solder lines, then I would measure the thickness of the shank, and cut the ring at the thickest part of the shank. Another thing to check is to make sure you are not cutting across any trademark or karat stamps, These are important for the integrity of the ring.
I usually like to cut in the center of the bottom of the shank if possible, but again, every ring is different, so you will have to do some investigating to see where the best place to cut. In this example, I have chosen the center. I am using a saw blade size that is 3/0 Sawblades. This is my “utility blade” and the size saw blade I use for most jobs. After I cut the ring, I place it on the mandrel and pull it up to the size I need. I size it so that the leading edge of the ring just touches the size I am wanting. Some people debate where to size the ring on the Ring Mandrel, so the ring just touches the size? So that the center of the ring is on the line? I am of the opinion that if it just touches the line on the mandrel, that should be the size you are wanting, and if it is a little small, it can always be increased a little with a flat Chasing Hammer. It is always easier to increase a little than decrease a little, which requires cutting and soldering again.
After the ring is cut, I use an Equaling File, a file that has teeth on both sides parallel to one another, to make sure the inside of the cut is smooth and evenly parallel. This is important for a clean union, and will reduce soldering pits. I find a piece of shanking material, about the same width and thickness as the ring shank I am soldering to. Since I am increasing the size of this ring by 2 sizes, I will cut a piece of material 5mm long, which is 2.5mm per size increase. I make sure the ends of the piece of shank I am using are filed straight and flat. I insert the piece of shank into the ring. I use the tension from the ring to hold it in place. I am careful to line up the INSIDE of the piece to the ring on one side. I will solder this side first. I dip and swirl my ring in a mixture of Denatured Alcohol and Boric Acid Powder. I have this premixed at my bench in a small baby food jar. I use about 1.5 oz. (jar about ¾ full) to 1 tablespoon of Powdered Boric Acid. I mix this good before I dip my piece into it. Make sure the lid is on tight when done, or it will evaporate quickly. After I dip the piece, I let it air dry. This ensures there is a good coating or barrier of the boric acid on the piece during soldering. This is used to help prevent fire-scale on the piece while soldering.
While soldering, I use adjustable tweezers on a base called a Third Hand system. This elevates the piece and allows me to position the ring so I can solder it. I apply flux Handy Flux to the solder joint, both the top and bottom. I use a piece of solder, in this case, about 1mm wide and the length of the shank width. I heat the ring up until the flux bubbles, and once it quits bubbling, I add the solder to the top of the joint, The flux will hold it in place. I heat the ring from the inside of the shank, and “draw” the solder through the joint, to ensure the solder has completely filled the union of the two pieces. This is what is referred to as “Sweat Soldering”. Solder follows heat, so it will be drawn through the solder joint towards the flame.
Once I have this side soldered, I let it cool, use my Equaling File to ensure the next solder joint is flush and clean. I carefully line up the inside of the next solder joint, and repeat the process. I like to take extra care to line up the inside of the shanks, because it takes more time to file the inside of a shank to make it flush, than the outside. I use a Half-Round Ring File to remove any excess solder from the inside and smooth the solder joint. Then I use a sandpaper sanding drum to remove any scratches. I start with 400 grit, then 600 grit, and finish with 800 grit drums to give me a very smooth area. Once the piece is in shape, I place it on my mandrel to make sure it is nice and round, and it is the proper size.
I use a #4 Hand File on the outside of the shank to remove any excess metal and to blend the shank and the soldered in piece. I finish the outside of the surface with a file to blend the shanks together, and finish with sandpaper as well as the inside, and finish the job with a good polishing job. The smoother and less scratches there are on the surface before polishing, the easier and better the polishing will be and look great.
As Promised, I have created a FREE Downloadable Quick Guide for you to help remember the steps I used in this Tutorial:
I hope this helps you to have the courage to attempt the next sizing job you are a little afraid of attempting. As far as your friends infected toe or enlarged goiter……. Refer them to an expert.
Now Go Make Something Larger!
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