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TeeDee
30-09-2015, 07:16 PM
The more I research polishing, the more I realise what a complex subject it is ( well for me anyway)
I am really struggling with getting a perfect shine on flat sterling silver surfaces. Curved ones seem to be less of a problem formsome reason.
The main issue seems to be right at the finishing stage where an orange peel effect or sometimes worse, 'whip' marks seem to appear. At first glance all seems ok but a recent customer 'observation' has made me question my current processes which are generally to work up through abrasive grades up to P1200 then tripoli either on a bench polisher or foredom motor and normally finish with a WDR mop.
I dress my mops regularly and singe when necessary. I dont mix compounds on the same mop.
I use Menzerna P175 or M5 to finish and sometimes use P164 as an intermediate prepolish.
I use quite light pressure for finishing.
Looking back through some old posts, Dennis suggests micromesh so I bought some. The pictures shown are of a tie clip micromeshed to 12000 grit which was then nearly scratch free until I used the WDR and finish polish. Lo and behold...... Pitting again! Although I'm not sure how well it will show up in the photos.
Worse still I tried to improve it using a Town Talk silver cloth and got even worse scratching for my pains.
Any help would be appreciated as I really dont want to disappoint my customer.
Tim

Dennis
30-09-2015, 09:09 PM
Well Tim,

The scratches are due to some new grit, which you have picked up on your cloth. Work areas are full of gritty residues, so keep polishing cloths in sealed bags when not in use.

The pitting is picked up at some time during construction. Presuming it is not a casting (and therefore not porosity), but made from metal sheet, it could be from rollers on a mill, needles in a tumbler, or resting on a hard work surface (or bench peg) with gritty bits.

Dennis.

TeeDee
01-10-2015, 02:14 PM
Thanks Dennis,
The Town Talk cloth was relatively new and does live in a plastic bag in my wife's sewing room where we do any final hand polishing prior to packing but I take on board your comments about contamination.
I did read recently that highly polished surfaces deserve a rouge cloth as anti tarnish cloths themselves can cause micro scratching.
The piece shown is of the same pattern ( but different finish) as that shown in this photo. It is in effect made from virgin stock with very little work other than the two bends over a 6mm drill end along with hallmarking and subsequent finishing. I guess there is still capacity for contamination at any stage although I do try to work clean.

I think also one of the lessons I'm learning is how easy it is to mark a mirror shine. The piece in my first post is a practice piece that I though I'd work on whilst waiting for my customer to return her piece.
I improved it slightly and today took it into a well established trade jeweller friend in Plymouth. His reaction was 'what's wrong with it?' And then proceeded to rub his finger over it which scratched it up a treat! Point taken!
Still a bit mystified with the orange peely/pitting problems but will be taking even more care in future.
Tim

Dennis
01-10-2015, 05:05 PM
That's utterly fabulous now Tim. Regards, Dennis.