Polishing, buffing and finishing are all terms for the same process, namely the removal of scratches from a surface to create the desired level of reflective brightness. Each step of the polishing process uses increasingly fine abrasive compounds until the desired degree of polish is obtained. As the visible scratches get finer, the more reflective the surface appears. Most commercially produced jewellery is polished to a mirror finish. Handmade jewellery can be made more distinctive by selectively using other finishes, such as a satin sheen or a wire brushed effect. Using a motorised polishing machine is an effective way to obtain an even result.
Health and Safety
Always wear a dust mask and eye protection to protect yourself from debris during the grinding process. On larger pieces of work, gloves should be worn as the polishing can produce a lot of heat.
Process
Motorised polishing creates a lot of mess, and should be kept separate from the rest of the household and other jewellery making areas. If this is not possible to achieve then hand finishing techniques should be used; these slower processes result in less debris being distributed into the local environment.
There are 2 general stages to polishing jewellery:
- Pre polishing - Medium hardness spiral sewn mops are used with a coarse polish such as Tripoli. This produces a brushed satin effect.
- Bright finishing - Loosely sewn buffs are used with a fine polishing medium such as Jeweler's rouge to produce the final mirror finish.
1. Pre polishing
The article to be polished should already be free from major defects and surface irregularities. Needle files should be used to refine and shape the object if necessary; the polishing process should remove as little material as possible.
A bar of coarse compound should be held firmly against a spinning mop for a couple of seconds. Too much polish will result in dirty streaks of compound to be transferred to the item to be polished. Applying insufficient polish will result in damage to the mop. If little polish is applied often, the situation can be easily monitored. Any build up excess polishing compound or metal dust can be removed by applying a stiff wire brush to the spinning buff.
When polishing, progress methodically across the entire article. After each complete pass, rotate the article so that the lines produced cross over at 90° to each other. By changing direction, the previous marks will be cut down thereby reducing them in depth; this will produce a smooth, even finish. Continue this stage until a smooth brushed satin effect finish is achieved. If all the previous scratches have not been removed, go back a stage and refine the surface using emery paper or fine needle files before returning to the pre polishing stage.
2. Bright finishing
For this stage, use a softer mop with a fine polishing compound such as Jeweler's rouge. At this stage, only a tiny amount of material should be removed from the article.
Carry out the polishing in the same methodological way as the previous stage; using less and less pressure with each pass until a bright mirror finish is achieved.
Finally, any greasy marks can be cleaned off with Vienna Lime Powder on a soft dry lint-free cloth. Alternatively, the article can be washed using washing up liquid and water on a clean rag.
Tips
- Work evenly, ensuring that the object is completely worked over with one compound before moving onto the next stage.
- Take care to not put a chamfer on sharp corners; it is all too easy to loose definition of fine details with motorised polishing.
- Each pass across the polishing mop should be done at 90° to the last one.
- Use polishing compounds sparingly, otherwise dirty grease marks will appear on the article.
- Adopt a 'little and often' approach to applying polishing compound and checking progress.
- Do not mix different polishing compounds on the same mop.
