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Vanessa
07-01-2013, 08:47 PM
Hi

I have a problem that I cant seem to solve when it comes to polishing a piece I made from silver. Somehow there is a scratch that has appeared on my piece and I can t get rid of it. I have gone as far back as 150 grit and have used arkansas stone to remove this scratch, I get to a point where I think I have removed it, work my way back up to the final 'grit' (12000 - I use the micromesh polishing cloths as it brings pieces to a lovely shine) before polishing on the mops and its at that point I discover the same scratch popping up again I have been trying for weeks to get this scratch out and I dont know what I am doing wrong. I havent had this problem with any of the other pieces I have worked on. I cover the surface I am polishing with with a soft cloth or leather chamois which I dust out regularly so I dont create any scratches in my pieces and keep the blue plastic on the silver for as long as I can, I've checked the surface I am using to polish on for any objects that may be the cause and I can t see anything. I've gone down and up the grits so many times I'm begining to think I may wear a hole in the piece eventually! I'm so frustrated but determined not to give up. Can anyone advise please? Do you think its the micromesh cloth scratching the piece, cant see how it can be though ?

Thank you V

Tabby66
07-01-2013, 09:00 PM
Without seeing the piece I would suggest going back to your buff stick on a medium grade and once a clean even surface is achieved, go back to the micromesh and work through the grades.....(is the scratch in the same place?? If so it's likely to be in the original piece, if it was a 'particle' on your polishing gear it would be recurring all over the place.....) Good luck, post a piccie if you can ;)

Dennis
07-01-2013, 09:10 PM
Hi Vanessa,
If the same shaped 'scratch' appears in the same place despite vigorous abrasion, I suspect it is a crack and not a scratch. Your best option then would be to fill it with solder.
Dennis.

mizgeorge
07-01-2013, 09:13 PM
Just beat me to it Dennis!

Vanessa
07-01-2013, 09:45 PM
Hi Vanessa,
If the same shaped 'scratch' appears in the same place despite vigorous abrasion, I suspect it is a crack and not a scratch. Your best option then would be to fill it with solder.
Dennis.
Hi Dennis - excuse me if i am being dumb but I dont think its a crack it doesnt go all the way through to the other side - if it is a crack how do I fill it with solder I didnt think you could?


Without seeing the piece I would suggest going back to your buff stick on a medium grade and once a clean even surface is achieved, go back to the micromesh and work through the grades.....(is the scratch in the same place?? If so it's likely to be in the original piece, if it was a 'particle' on your polishing gear it would be recurring all over the place.....) Good luck, post a piccie if you can ;)
Hi Tabby its a scratch in the same place. I had thought that too if it were a foreign particle in the polishing equipment then it would appear all over and my other pieces would also be affected. It's frustrating. I've gone up and down the grades endlessly trying to get this scratch out. It has to be the most frustrating thing in the world at the moment - but I will not give up on it!

Dennis
07-01-2013, 10:52 PM
If silver is overheated or disturbed when glowing hot it can develop a surface crack that does not necessarily go all the way through. As you describe it, it is very narrow, so flux and tiny crumbs of hard solder should do it.

Support the piece so that the defect does not tend to increase and heat slowly with a bushy flame so that the solder melts slowly and trickles in to fill it.

I hope this works, as my reputation is on the line, as is George's with whom I have a thought transference thing going. Dennis.

Patstone
08-01-2013, 06:11 AM
Could it be a fault in the silver sheet manufacture? Are there any visible scars on the rest of the sheet. Just an idea.

Goldsmith
08-01-2013, 09:57 AM
Vanessa, silver sheet is not always perfect, sometimes in the melting to ingot process the silver gets an air bubble inside and when the ingot is rolled the air bubble flattens and the sheet looks perfect, but when heated the flattened air bubble will expand and break through the surface giving a crack appearance. Sometimes the whole surface can peal off when polishing. I must admit that when this happens there is no easy fix, yes you can possibly run solder into the crack, but there is no guarantee that the solder line will not show up when polished. You could change the design and perhaps add some texture on the surface to hide the scratch line.

James

Dennis
09-01-2013, 07:54 AM
I can see that happening when you roll your own from ingots, James and it must be disastrous for a really important piece, but I've never had it with Cooksons. As for Blundells before them, they were so dedicated to what they did, that if you started accusing them they might well have asked you not to darken their doorstep again. Regards, Dennis.

Vanessa
28-01-2013, 08:30 PM
Thought i would update you all with a very odd occurance! I put the piece to one side exhausted by my many attempts at getting rid off this crack / scratch as I needed to look at it again with a fresh eye before attempting the suggestions you all put forth. However with the heavy snow I have been 'locked out' of my workshop couldnt get in until the weekend. Once in I was shocked to find everything stored in the cupboards had frozen solid including the safety pickle (thankfully the glass jar didnt crack) and the heat insulating paste! Anyway after much sorting through things and careful defrosting I thought I would have a look at my pendant. Now prior to putting the pendant aside I was giving it one last polish and managed to snap the 'antennae' off of the butterfly pendant I was making thats when feelign deflated I chose to put it one side and come back to it as I was only making things worse! Anyway after I had sorted through all the frozen items I turned my eye to sorting out my butterfly resoldered the antennae to the piece and as I was polishing the item I noticed that the scratch/crack had completely disappeared! - I wasnt soldering anywhere near there so it isnt likely that I have inadvertantly repaired it with solder as suggested above! Now I wonder whether (as it was in a box with various stones that all cracked in the ice) I wonder whether freezing the item somehow contracted the metal thus repairing it? - I dont know how to explain where it has gone!

Anyway i am thrilled and have set the stone (first time I have ever set a stone and really pleased for a 1st attempt not perfect at all but I am pleasednI've set it and it doesnt need any glue!) and have ordered a chain so once complete I will photograph and post for your opinions and suggestions and critique please if I may (there must be a thread soemwhere for this purpose). Though it will have to wait as I am prepping for my interview that is just around the corner and will be super pleased to take this piece with me!

silken
28-01-2013, 09:26 PM
Hmmm, it must be those mystical snow fairies!

In all seriousness, I have no idea if that is possible. My metallurgical knowledge is definitely not excellent but it seems unlikely that the low temperatures could somehow burnish away a fault/crack in the metal. I was following this thread before so I'm glad you've been able to complete your piece! Would love to see the pic :)

Good luck at your interview!

Dennis
28-01-2013, 10:30 PM
Well, you're a mystery woman and no mistake. This will bring on a whole lot of new suggestions about the paranormal. Perhaps you have a spirit guide, or it was simply a hair from your dog on your specs. ;-D Dennis.