silver soldering

Gold & Silver Stacking Rings

12.09.2011 by Eileen Moylan //

This week I’ve been working on a set of gold and silver stacking rings. I did a number of sketches and the customer decided on these rings with little gold triangles dotted across the three bands. I’m making sketch number 1 on this page with all the gold triangles going in different directions.

I’ve cut the silver wire and rounded it up to the correct size of ring. Sorry I forgot to photograph that part but if you want to see it have a look at the post I wrote on making a silver ring.

Once I have the rings set in place and the joint perfectly lined up I can being soldering. I begin by heating the entire ring and then once the heat is built up I can concentrate on the joint. I do this with silver as it is such a conductor of heat the joint would not hold the temperature unless the entire ring was already hot. The silver solder and flux is positioned on the joint and once it begins to melt I keep the flame on it. This is to make sure the solder runs into the entire joint and gives me a seamless joint. I let it cool down, pop it in the acid to clean the metal and then rinse it in water and scratch brush it using a brass wire brush.

With stacking rings it’s important that all the rings are exactly the same size and they sit perfectly together so I clean up the soldered seam and using emery paper clean up file marks on the edges of the rings. I use dowel rod with different grade emery papers to get into the inside of the rings. While it’s a slow process it’s best to start with the coarse emery paper and work your way down to the finest grade so you have less polishing to do at the end.

I also use a pig skin with polishing compound to give the flat edges a final polish before I begin the next stage of cutting out the gold triangles and soldering them onto the silver rings.

I’ll post photos of this next week…

Have a good weekend!

My Jewellery Bible, by Oppi Untracht

03.18.2011 by Eileen Moylan //

The other day in the workshop I reached for my battered copy of Oppi Untracht’s ‘Jewelry Concepts and Technology’ to solve yet another problem. This book is like the bible of jewelery making and has served me well over the years. So today I’m dedicating a post to Oppi to share this brilliant book with everyone else.

Jewelry Concepts and Technology’ Oppi Untracht

Oppi Untracht was an American jewellery teacher and historian who trained and taught in New York but later moved to Finland. He has written a number of books on jewellery and metalwork. His best known were ‘Jewelry Concepts and Technology’ and ‘Metal Tachniques for Craftsmen’.

When I first got the book years ago it was on the recommendation of a South African jeweler I worked with. She’d occasionally mention that she had checked different things with Oppi and I just presumed it was an friend or old lecturer she was referring to. The minute I found out that all this knowledge was coming from a book and I too could have my own “Oppi”, I snapped up a copy!

I’m delighted to say Oppi has rarely let me down in that eight years. I’ve dragged this heavy book out for everything from starting new projects to idle curiosity. There will be times when I’ll be a bit rusty on different techniques and I dip in to the book quickly to check I’m not about to burn off my eyebrows! Sure enough, Oppi will provide the answers. Because I didn’t study jewellery in college there are some techniques that I’ve never had the opportunity to try. This book is great because it allows me to research different techniques from the process through to the finished piece. While I may need to get some extra help elsewhere on modern procedures (the book was published in the 80’s) I have a great basis on where to start. When I tried acid etching this year the majority of the information came from this book. He goes through different types of surface ornamentation from around the world like the Japanese Mokumé Gane. As well as lots of technical information, he also looks at the origins of jewellery and why we wear it. He has a brilliant diagram that breaks down the various reasons for jewellery such as tradition, collection and fashion.

So for all of you who have never heard of this book definitely check it out and for those of you who’ve looked at it on Amazon and debated whether it was worth the money take it from me, it is!

Fire Stain: What is it and how to prevent it

03.14.2011 by Eileen Moylan //

This week in the workshop I had the hassle of dealing with fire stain. If you have tried silver soldering you may be familiar with the scourge that is fire stain. Just when you think you’re nearly finished and you begin the final stages of polishing on the lathe those nasty little blotches appear. For those of you lucky enough not to what this looks like it is a pink or purple stain that can develop in sterling silver during soldering.

Here’s the science bit… The oxygen in the air penetrates the outer surface of the object oxidizing the copper content in the sterling silver. The silver is then pickled in sulfuric acid which removes the oxidized copper on the surface. This oxidisation is known as fire scale. The difference is that fire stain can’t be removed in the pickeling process. The problem with fire stain is that it discolours the reflective nature of the polished silver and either needs to be covered by plating or filed away.

Mostly you don’t see the extent of the fire stain until you have the piece polished and finished. The best way to see it is to hold the silver against a piece of white paper. This way you have a uniform white reflection on the silver that highlights the pinky purple stain.

Here’s a photo of a cuff link that I made recently that had some fire stain. You can see the pink blotches on either side of the cut away circle design. There are lots of things you do to remove fire stain which involve chemical solutions or silver plating. Unfortunately this can be expensive and because it doesn’t happen me that often I haven’t seen the need to invest in them. The other method for getting rid of the fire stain is by abrasive removal using either a polishing lathe or other abrasive techniques. I think the best way to remove it is to use some wet emery paper on the stained area. It can be slow work but it allows you to concentrate on the area as opposed to a polishing lathe which can soften the sharp edges and detail of a piece. Once you have removed the patches of fire stain you can then finish the piece on the polishing lathe.

Removing fire stain with wet emery paper

The ideal solution to fire stain is to prevent it from happening in the first place. As the oxygen is the cause of the stain many silversmiths recommend creating oxygen free conditions when soldering. Ganoskin have a good piece on how to go about achieving this, to see it click here. I find the best way to prevent fire stain is to make sure you are using the correct size flame for the piece you are soldering. A very hot flame can over heat the piece but also a flame that is too soft means it takes much longer to melt the solder. Both these problems can cause fire stain. The other thing is to make sure the piece is clean so you don’t need to prolong the soldering process due to dirty metal.

Hope this helps in the fight against fire stain!

About

Silver Ring Part 2

12.17.2010 by Eileen Moylan //

This is part two of making a silver ring. If you want to see part one just click here.

When the ring has cooled down it is put in a diluted acid solution. This cleans the silver and removes any traces of flux.

The ring is rinsed with soapy water and scratch brushed. Scratch brushing is done using a brass wire wheel rotating slowly on a lathe. Here I am just using a brass wire brush to clean the metal.

The ring is hammered again on a ring mandrel. Once the ring is perfectly round the joint is filed to take away any excess solder that may be on the outside of the ring. If the inside of the ring has excess solder this should be removed before the ring is hammered on the mandrel as it may affect the shape of the ring.

The file marks are removed using a fine emery paper before the ring is ready for polishing.

Polishing is done on a lathe. This lathe has two cloth mops, one to remove the scratches from the ring and the other to give the metal a final polish.

Silver Ring Part 1

12.08.2010 by Eileen Moylan //

When I get an order for a piece of jewellery such is my enthusiasm to get started I forget to document the process for my blog! This week I decided to make a simple silver ring and photograph each stage of the process. Here are the photos from today’s work.

I first start by getting the piece of silver wire and measuring the length I need. This is determined by the finger size. Since this piece isn’t for anyone in particular, I’ve made it quite large as it should be easier to photograph.

Having decided on the length, I cut off the extra silver. The wire is held in a ring clamp (above) and cut using a jeweller’s hand saw. The saw I am using I got from Otto Frei in San Francisco. It’s an aluminium frame and unlike the traditional jeweller’s saw it is not as flexible so you don’t break as many saw blades. They say that they make the handle and frame red because clinical trials have shown that the colour red promotes accuracy!

I then use a ring mandrel (above) which is held in a vice to hammer the length of silver into a ring shape. This is done using a rawhide mallet so as not to mark the metal.