My Silversmithing Basics.... Long!!

[helenfc]

I had to condense my notes from early last year at uni a bit as they were a mess and I wanted them typed up. This is really "metalsmithing 101". Just dawned on me it might be useful to someone on here? If it is in the wrong place feel free to move it and if it is too long, maybe someone could tell me how to replace it with a link   

Annealing and Pickling

   Whatever metal you are using, it will be far easier to use once it has been annealed. Annealing is the process of heating the metal to disperse the particles within it to make it more pliable and malleable. When metal is in its original sheet form it will be stiff and and difficult to bend due to the complex and almost brittle system of molecule structures within it. When heated, the metal reacts to the increasing temperature by breaking some of these structures, which makes it more malleable and easier to manipulate.
   The process of annealing is as follows:
      1. Have the metal on a heat proof surface such as a firing brick or a charcoal block.
      2.Turn on the torch and begin to circle the metal, making sure the full surface area is evenly heated.
      3. The surface will eventually turn a glowing orange (for silver) or cherry red (for copper and brass) colour. Once this colour is acheived, take the heat off the surface immediately.

   Your metal will now be annealed and much easier to use. However, while heating the metal, you will have brought some 'scum' to the surface, giving the metal a charred, uneven colour. To regain the original colour, you will now need to pickle your metal. The pickle we are using today is a safety pickle, an acid powder which is added to water to make a weak yet effective cleaning solution for your metal. The acid eats away at the surface 'scum' leaving the metal in its original state. Once the metal is out of the pickle, you will need to polish it up to acheive its shine, although sometimes it can be quite beautiful when left matte as well.

NOTES: You will have to allow for different annealing times depending on which metal you are using. Copper has a very high melting point, so you can keep it at the cherry red stage for longer (this is why our practice solder is on copper). Silver's melting point is lower, and from experience, it is possible to melt it (!), but if you are careful and pay very close attention to it, it will be fine. It is about to melt when you see a very shiny surface appear on it, but the annealing point will have been reached before this. Brass also has a high melting point, though it is more difficult to solder than copper, which will be discussed in more depth later on.

Piercing

   As most metal comes in sheet form, before you do anything to it, you will have to pierce (or saw) the metal to the size and shape you wish to use. To do this, it will help you to anneal the metal first, as the jeweller's saw will slide through the annealed particles much easier than the brittle, pre-annealed ones. Because the teeth on the saw blades are so small, it is possible to saw very tiny, intricate patterns into the metal. What I find helps me is to use a felt-tip pen to draw the shape I would like to use, as it helps to guide where you go, and felt tip can either be washed off or removed in the pickle. Saw blades break easily, but there are precautions that can be taken for this. I always run my saw blade through beeswax to lubricatie it and help it glide through the metal more easily. Antoher thing which is absolutely essential to remember is to always hold your saw at a 90 degree angle to the floor. I can't stress this enough!! If the saw is not vertical then the blade will not go through the metal evenly, resulting in jaggy edges and broken blades.
   To insert the blade in your saw frame:
      1. In the V-shape cut in your bench peg, place the end of your saw frame. Sit close to the bench peg and lean the saw handle against your breast bone. This way you will have two hands free to work with as it can be fiddly!
      2. The blade's teeth should be facing towards you as you insert it. Undo the screws on either end and slip the blade in, teeth facing up the way, and towards your torso. Screw it in at both ends.
      3. If it is not taught then use the screw on the top of the frame to lengthen the blade so that it is rigid in the frame.

   Sawing the metal:
      1.Run the saw blade through your beeswax.
      2. Draw the line you would like to cut onto the metal with a felt-tip pen.
      3. Position the starting point on your bench peg and gently draw your saw vertically through the edge of the metal creating a a small groove.
      4. Place the saw blade in this groove and begin moving it up and down keeping your perpendicular angle to the floor. Keep a steady pace, there is no need to go too fast, as this can cause the saw blade to overheat and break.
      5. If you wish to cut a pattern rather than a straight line, move the metal to mirror this, rather than the saw blade, which should alvays be going into the V of the bench peg. Turn the metal to make the blade follow your pen line.

NOTES: The blade cuts through the metal as it goes down the way, so this is where you want to apply a bit more pressure. If your blade breaks, don't worry, it happens! You can actually re-use it by adjusting the length of the saw frame if you feel like being very economical, otherwise just change it for a new one. If it feels as though it is getting more difficult to cut as you saw through the metal, re-lubricate it with the beeswax being as liberal with it as you wish.

Hammering and Shaping

   This part is quite self-explanatory. Make sure your metal is still annealed enough after sawing to be manipulated by pliers. You really now have a free reign to give it waves and crinkles and just experiment...if you don't like it, it can be reversed.
   In terms of hammering, there are two main effects you can acheive with it. Firstly, metal hammers can be used for flattening metal and texturing it all depending on what the head looks like. Any metal hammer can give an interesting texture to your metal sheet, and it is definitely worth your while to play about with some annealed scrap metal when you get a chance to see what results you can get.
   A hammer is also very useful for shaping your work, for example rings and bangles or raising bowls if you are getting advanced. So as not to mark or texture these as you are working with them, the best thing to do is use a soft suface hammer, the most common being either rubber or raw-hide based. Wooden ones are also available specifically for raising.

Drilling

   We will be hand drilling our metal, easy and cheap for thin sheet. Anneal the metal again if you feel it has been work hardened by this point (piercing, hammering and manipulating it with pliers all work harden the metal by re-aligning the complex molecular structurs discussed earlier).
   To drill the metal:
      1. Choose appropriate drill bit and insert it into the pin tong.
      2. Using the centre punch and a hammer, mark the spot you would like to drill through.
      3. Slowly start turning the pin tong in the correct direction and continue at a steady rate until the drill bit is clear through the metal. (Make sure you are doing it on top of the anvil of your bench peg...we don't want any holes in your wooden table!)

Soldering

   Now that you can anneal, soldering is the next step up with the torch. The most important thing to remember when you are soldering is the position of the heat. The metal should be warm all over, not just on the solder, or the solder will refuse to flow. It is also important to heat the metal on both sides of the solder because solder flows towards the heat. If you heat only one side then the solder will adhere to that side only and not join the two pieces. Also extremely important is to make sure the two pieces you wish to solder together are sitting 'flush', which means they should have no gaps where you wish them to join; solder will not fill gaps. This can be acheived using needle files, sandpaper and larger steel files.
   Once the join is flush, you are now ready to apply the form of solder you are going to use. If you are using silver solder strip, you will have to cut it into small squares, called pallions. You can do this with preferrably tin snips, or cutting pliers and scissors will suffice. To use the pallions you need to use flux. The flux is there to help the solder to run, and to prevent the metal from 'firestain'. We are using Auflux, which is a premixed flux that needs to be applied with a paintbrush to the join and pallion. The other option is solder from a syringe. This is a premixed solder and flux solution that applies onto the join with a paintbrush as well. The syringe option is much less hassle, but more expensive.
   Once the solder and flux are applied to the join, you are ready to heat the metal:
      1. Place metal onto the soldering block with your preferred solder/flux mix applied.
      2. Turn on the torch and start slowly circling the piece to give it an eved heat.
      3. Once the piece is heated (this will depend on the metals size and thickness), concentrate your flame on the solder join until you see the metal glisten and then spread. Remove the heat once you have seen the solder spread.
      4. Pickle the piece
NOTES: You can mix your own flux solution using a borax cone, ceramic dish and water. This is cheaper than Auflux, but more difficult to mix to the right consistency. Another point is to be careful when soldering two things on the same piece. If solder has been joined, it is possible to melt it right apart again if you are not careful. Thermogel is brilliant for this. It is a heat proof covering that works for protecting stones and previously melted solder joints from the effects heat can have on them. If your join is not fully soldered, run a saw through it and try again; the saw blade will create two even, flush sides which should fuse together nicely. Brass is a bit of a pain to solder, though it can be done. This is because the silver solder does not adhere to its surface easily due to it being an alloy of metals, with a more complex molecular structure. Since silver and copper are elements they take to the solder better.

Polishing and Finshing
      
   Once your piece has been removed from the pickle you will be able to polish and finish it using a variety of ways. These include burnishing, sanding, filing and brushing. We will go through these in detail in the course discussing the different finishes which can be acheived with each. Tumbling is also an option, but investing in a tumbler can be quite expensive.
   Filing to reduce the appearance of a solder join:
      1. Remove piece from the pickle
      2. Using a needle file, gently file away the visible solder by pushing the file away from you.
      3. Alternate the use of the file and sandpaper to make the join as invisible as you can (NOTE: This is much easier on silver than copper as the solder itself is silver).
      4. Don't forget to do both sides of the join; if it is on the inside of a ring shank, use a half round file.

Phew!! I hope you like it