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Dennis
11-02-2013, 09:32 AM
If you look back over the last few years, you will find loads of advice on how to deal with scratches and other blemishes. So much so that it sends out a message that aggressive finishing is a normal part of jewellery making.

I strongly disagree and in fact consider it a sign of failure, my own included. So starting with a pristine piece of metal, maybe freshly unwrapped, I would like to offer some suggestion on how to avoid damaging it. I hope you will join in to add your own ideas.

1.Scratches caused by grit and filings.
Work in a clean environment , by using a brush or cloth to remove grit and filings from your worktop and bench peg.

2.Damage due to tools.
Where possible, guard the beaks of pliers with short pieces of polythene tubing. Add fibre jaws to your bench vice, or for a hand vice use masking tape.
When setting stones wrap your piece in generous amounts of masking tape, leaving only the setting exposed.

3.Firescale.
Try to avoid firescale in sterling, by heating with a bushy fame and keeping the torch moving. Working in subdued lighting allows you to see wen too much heat is being directed to one part.
Prior to annealing, brush a flux solution onto the warmed metal to resist oxidation. Firescale is less visible on textured , matte and satin finishes

4.Stray solder.
Before use, check your soldering block for unwanted pallions of stray solder. Once a piece is fluxed and the pallions placed, apply the heat very gently at first to allow the flux to dry out. If a pallion jumps off, retrieve it so that it can’t cause a blemish elsewhere.
Where possible use sweat soldering and bevel the lower edge of the add-on to hold back the flow of solder.
Ghosting occurs when a joint is heated so rapidly that the solder, instead of melting, sinks into the metal leaving a negative image, or pit. Always begin by applying heat at some point furthest from the joint.

Dennis.

GreenSnail
11-02-2013, 09:18 PM
Thanks for this, Dennis- I've been trying to figure out why the solder pits into the metal.

I'm not exactly sure what this "Where possible use sweat soldering and bevel the lower edge of the add-on to hold back the flow of solder." this means exactly....could you explain further please?

Dennis
12-02-2013, 07:55 AM
Hi green snail.

Sweat soldering is when you melt solder onto one component then put it where you want it and heat again. Provided you have judged the amount of solder correctly, the two parts will join neatly when the solder melts a second time.

If what you are adding is a sheet or something with a base you can bevel the lower edge so creating a tiny wedge shaped gap. This will fill up, but discourage the solder from flowing out.

Sweat soldering is also useful in the case of items which you need to add to castings, or metal clay, because these are more porous and blot up solder. Another example is adding a small item to a much bigger one.

In each case you sweat some solder onto the smaller item first and apply the heat to the larger item until, heated by conduction, the solder flows.

It might be difficult to heat the main body of your piece unless you can get the flame underneath, by raising it on a steel gauze and some blocks, or a tripod. Alternatively you might succeed by fiercely pre-heating your block. Dennis.