Time to polish….Lost Wax Casting (Part 3)

Time to roll up your sleeves, because the real work is about to begin! Maybe if I chose to make designs that didn't have quite so many different planes and curves, then polishing would be a breeze, but I don't play like that! Why should I make it easier for myself?! Every time I tell myself, "Ok, Louisa. Seriously. Lets try to make something simple this time!", it never works! I just don't think I am wired that way. I approach salad making in a similar fashion. I will start with some lettuce, then add some broccoli, then beets, tomatoes, nuts, cilantro, chicken, mushrooms.... I think you get the picture. I end up with a goliath salad with everything but the kitchen sink in my huge salad bowl! Ok, enough chit chat... Lets start polishing.

Sprues

Cut SpruesThe first step is to cut off all the (now silver) sprues that you so carefully attached in the wax. You can either cut them off with sprue nippers or you can saw them off using a jeweler’s saw. I prefer that latter, because you get a more precise and closer cut with the saw, but if you are impatient like I am, then chances are that you will go through A LOT of saw blades. Jeweler saw blades are very thin and will snap in half very easily if they are torqued too sharply in any given direction. I normally let out a slew of expletives while going through a whole package of saw blades in a effort to saw off my sprues. Once the sprues are cut off, I will smooth out the rough edges with first a course and then a finer file. I will also use a steel bur for the hard to reach areas. A lot of the burs used by jewelers are similar to those used by dentists and, in fact, I got my favorite burr from a dental catalogue.

After all the sprues have been cut off and filed down, it is time to polish the whole piece. I am sure that every jeweler has their own various techniques and favorite abrasives that they use to polish, but I love blue wheels! The blue wheel comes in various grits and is great when polishing undulating and irregular Blue Wheelsurfaces. I will start with a pretty course blue wheel and then gradually more down to a finer wheel once I have smoothed out all the most obvious surface scratches. I love working with sheet wax because it is very malleable and is easily shaped with your hands when warm, but it is a pain to clean up! It is very difficult to get sheet wax completely smooth before casting it into silver and I will often see traces of my finger prints that have been transferred from the wax into silver. For the hardest to reach nooks and crannies I will use little abrasive wheels that are shaped like pins, which of course, require you to go through a number of different grits until they are smooth.

Now that all the major clean up is finished using various abrasive wheels, I will move onto the buffing machine. Again, just like with the different blue wheels, I will start with a more course polishing compound, such as bobbing, and then move towards finer compounds, starting Bufferwith tripoli, then white diamond and finally rouge to give it that final high polish. The buffing machine is a wonderful piece of machinery, but it does punish those who are not paying attention! The machine I use has two arms on either side that spin around, which can hold various buffing wheels. I prefer large cloth wheels that are then charged with each buffing compound. The wheels will do a great job buffing out the remaining imperfections in the surface of the silver, but the second you let your mind wander and then wheel catches the edge of your silver piece, the piece of jewelry that you have so painstakingly polished will go shooting back and hit the back of the buffer with a really impressive thwack! This will usually happen to me just as I am putting on the finishing touches and will normally result in an impressive scratch right on the surface of my piece or a bent ring shank that will then require some hammering to bring it back to round.

Once you have gone through all the buffing compounds your piece will be fully polished and ready to go, unless you choose to oxidize the silver. In that case, you will heat your silver piece with a torch and dunk it in a particularly nasty smelling solution of liver of sulfur, which till turn the silver black.

Liver of Sulfur

Heating With Torch

 

 

 

 

 

 

 

 

 

Oxidized

I will then do one more turn on the buffing wheel or by hand with the flex shaft with the white diamond compound to take off any unwanted oxidation. I am sure by now I have dashed all your hopes of becoming a silversmith, but it really does look (and feel) great once you have gone through each step and end up with a fully polished piece of silver jewelry that was made completely by hand!

Lilly Ring Final Polish