QuestionI use silver solder paste to solder jump rings to the ends of chains. I finish by dipping the end of the chain in pickling waters. The ring and the chain (near the ring) become very dull and lack shine by the end of the soldering process. I have used a polishing cloth but the result is not very good. I read about things such as a polishing motor which comes with mops, powders and such but I am not sure if I could use any of these on such a small thin chain. If you could please advice as to how to get the piece shiny (on a budget under $200), it would be most appreciated. Many thanks.
AnswerHello Orli,
First of all ordinary paste solders are low temperature solders that contain tin and lead,and sometimes are silver bearing but are not intended for jewelry work.You need a solder paste from a firm like Cookson's in the UK that sells silver solder in an easy flow ( in your case- a small thin chain) melt point and you need at least a butane torch to carry out the operation adequately.It sounds as though you do have a jewellery catalogue on hand though and are at least in the right direction! But I would get used to working with sheet solder or wire and buying a charcoal block to do it on and absorbing oxides at the same time.It is a far more reasonable investment than a polishing motor and a valuable technique to learn if you make a fair number of chains.Pastes are intended for production line assembly of cheap jewelry.You would do yourself a favour to learn the method of soldering by melting a snippet of wire or using paillions of solder and melting them into a ball and moving it onto a heated join with a titanium , or stainless steel probe, pick or even a length of coat hanger wire sharpened to give a tapered end to make moving the melted ball into place easier.Of course all parts are fluxed: the jump ring, the chain end, and the solder.You can make small depressions in a charcoal block to contain the balls of solder so they don't jump off the block, and in buying charcoal buy the hardest to be had.It will last even longer if you wrap it with binding wire ( annealed black iron wire) and periodically rub the surface with sandpaper or on concrete to re-flatten the surface and remove any collected flux glass, or other chemicals that have accumulated.
One solution would be to reheat the repair and using desoldering braid (available at electronics and hardware stores like radio shack, etc.) absorb the excess solder, then dispose of that piece of braid ( a copper wire will also work but takes some skill, you can also braid together some thin copper wires and make your own braid by treating it with sal ammoniac as is used in stained glass making.All you do is make a water paste of the block with a few drops of water and a paintbrush, then paint it onto your braided wires and let dry, then use that to soak up excess solder by reheating the join) or using a good sharp bench knife scrape off all you can leaving it bright, then pickle it again.
Replace the jump ring previously used ( clip off the soldered area and throw it into the trash bin and reserve the precious metal for your refining) as it will now not be sized correctly. Using a clean and oil free jump ring, flux well and flux the cleaned end of the chain, and the solder (if you have some wire or sheet solder in a medium or easy flow as you don't want to melt down fine chain, that would be best to provide a strong join)- even if using a paste solder a product like Cupronil sprayed on warmed metal and the warmed jump ring or your own flux made of methyl alcohol, borax and water (4:5:1) and contained in a small misting sprayer will help the solder stick better.Remember to heat all the metal parts and build at least one layer of flux on each part before attempting to attach the ring to the chain.You may use a third-hand to hold the chain end, or crosslocking tweezers to hold it as well,it will also help absorb excessive heat to help prevent further fire scale or fire stain from forming once you have spent time removing it.
Many times pastes sit on vendor's shelves as most jewelers do not use it. There is a company in the US called "My Unique Solutions" that does ship to the UK and makes their own pastes in an assortment of flow points and metals, that are better than most on the market. Beth Katz owns the business and if you need her address I'm certain its on google search.You can also make your own paste of zinc oxide ( as lifeguards wear in full sun) and finely ground filings from piercing or sawing with a fine jeweler's saw blade the metal you need ( gold or silver), and adding a small amount of copper filings- basically a pinch of pure copper to a teaspoon of zinc oxide paste, a 1/4 th tsp of powdered borax ( for self-fluxing action) and 1.5 grams of fine silver filings will give you a usable paste that you make up fresh and has a flow point close to that of sterling.The more copper added the higher the melt temperature and flow point of the mixture.
But back to the questions. A polishing cloth that is abrasive would work if the metal is not fire scaled, or fire stained- which sounds like what has happened to you. If pickle doesn't remove it ( warm pickle that is, never boil it!), or if the pickle is a deep bluish green at this point it may be time to make a fresh batch. Just neutralise the old pickle with soda crystals before disposing of it into the water system, make a fresh batch adding acid to water and keeping it in a covered slow cooker or glass saucepan that can be repeatedly heated on a hotplate or stove to about 140 degrees F, not higher.
You should never attempt to polish a chain on a polishing motor- it will catch in the wheels or on the arbor and become a dangerous projectile that spins and cuts rapidly anything in it's path until the electricity is turned off. You can hold the end in a universal hand vise and polish it with a felt bob and rouge moving the chain as you finish an area or use a 3M radial bristle disc in the peach colour first to remove the stain ( 120 grit) and then following with a light green disc ( 6 micron finish) for a high shine on any precious metal.I love the 3M radial bristle discs and recommend them highly to any jeweler- if you want to invest in a great abrasives kit with no mess, buy the 3m master kit that contains an assortment of mandrels and discs in various grits from a 36 grit that is able to remove anything from any shape or crevice in the jewelry piece to 100 micron mesh for a high polish on any precious metal! It is well worth the investment and they can be used in a Dremel tool, any flexshaft or rotary tool.If you are making jewelry for a living then it may be worth the investment to buy a polishing motor, but for hobbyist jewelers a flexshaft or dremel serves the same purpose at an affordable price and is multi-useful in making small scale jewelry projects, as well as around the house for repairs and refurbishment. If you cannot afford the rotary tool and at least a few discs and a mandrel, try an abrasive paste cleaner like "Simichrome" brand,but if it's truly fire stained ( from too hot a flame concentrated too long in one area of the piece) you will need an abrasive to remove it.A felt bob in a rotary tool with the rouge that is included with most kits should have enough cutting action to remove it.Also the expandable drum and sanding band, a rubberized abrasive wheel, or some brass wool will all do the job equally well. If you have compounds on hand try some tripoli or bobbing compound first then finish with rouge or any precious metal compound designed to impart a high shine on silver ( Dialux brand is available from Cookson's in small bars that are relatively inexpensive and are of a quite high quality- you could purchase a cutting bar and a polishing bar for under 10 pounds total, perhaps with shipping if you don't live near a branch store in the UK).There is a polishing cloth brand called "Sunshine" from Rio Grande in the US and I believe Cookson's in the UK that contain micro-abrasives in the material and last a long time if kept contained in a plastic container, they work well on lightly stained metals but not on deeper fire scale in which case the radial bristle disc, or a sanding band, etc, as mentioned above is required,to remove the blackened areas, clean and prepare the metal for reattaching your jump ring to the chain end by soldering it to the end using at least a medium solder- try to avoid easy solders as they just aren't strong enough to take the force of hanging pendants and daily wear.Afterward you will want to pickle it if any flux glass is present then wash the soldered area in a soda and water solution with a few drops of detergent and pat dry, then polish as you like .
I always recommend not buying what you don't need.In your case a polishing motor sounds like overkill.Keep it cheap if you are not making a living from your jewelry making, but use the best possible tools and consumables in doing so so that you turn out a consistently quality product.
I hope this helped .
Best regards,Ari
