Lucidatura parti in plastica

[Ottorino]

Riporto da qui

http://www.vintagepens.com/pen_repair_donts.htm

POLISHING:

In the old days, if a pen was taken in for repair, it was automatically buffed before being returned to its owner. Many shops still do this. This is why nearly all brassing found on old pens and pencils comes from the polishing wheel, not ordinary wear and tear. The plating is invariably missing not where a pen is normally held or handled, but in those spots that stick out into the path of the wheel: the rim of the cap top, the top of the clip ball, the middle of the lever.

Polishing a pen by hand gives better results, but takes a lot more time (which should give you some idea of how potent a material-remover the buffing wheel is – much more potent than is desirable for plated metal). If you must buff, use tape to mask off the imprints and trim first. There is NO justification for putting an all-metal pen or pen cap on a buffer. Aside from causing brassing, it will instantly reduce crisp engraving and engine-turning to a blurry shadow of what it once was. Don't use Brasso on pens. It is extremely harsh, and leaves a residue that promotes trim-damaging corrosion.

Note that correct buffing wheel speed is related to the hardness of the material being polished. Hard plastics such as Lucite acrylic are quite forgiving, but softer injection-molded plastics can catch on a too-fast wheel, tearing and burning deep scars into a pen's surface. On very soft plastics such as that used for the Parker VS, machine-polishing should not even be attempted.

Finally, a warning about beryllium bronze, a material used for Parker clips from the Aerometric 51s on: beryllium is an extremely poisonous element, so never attempt to solder or weld broken clips that might contain it. Buffing intact clips on a wheel may also be risky.