Pitted silver

by Mandy
(Kent, UK)

Hiya

I have recently purchased a tumbler with assorted stainless shot and used about half a teaspoon of the abrasive soap powder that came with the tumbler, covered the load with water plus about an inch on top and left it on for a few hours. My silver disks, which have gold/silver granules soldered to them and the rest of my pieces all came out marred with tiny pits all over :O( It seems like the shot has marked the metal. Any idea why? I thought tumbling them would make them extra shiny as I had already polished them with the Dremel and rouge and expected a better, not worse result. I was hoping to not have to get covered in Rouge and have black fingers again... Can you help?

Mandy


Stacy's Answer:

Hi Mandy!

I'm not sure what the "abrasive soap" was, but the rotary tumblers we use are rock tumblers and sold as such. For jewelry, we "re-purpose" them to suit our needs by using stainless shot, water and dish-soap to gently tumble-polish our metal goods. Of course the sellers of the tumblers have no way of knowing what the machines are going to be used for. The abrasive powders used to polish rocks are damaging to metal. It is possible that the abrasives in the soap you used caused the marring and pitting.

While tumbling will remove slight surface blemishes, anything more serious will have to be polished out by hand. (sigh) Not fun! Try wearing tight-fitting (so the glove material does not interfere with the rotary tools) Nitrile disposable gloves for hand-polishing work to help prevent the rouges from being ground into your skin....saving lots of clean-up time and cleaner hands for you! Most disposable-style gloves will work, I've just found the nitrile ones to be a bit more durable.

So that you may enjoy the benefits of your tumbler, thoroughly clean the shot and the barrel until they are free from all of the abrasive residue. Use only water and liquid dish-soap. A de-burring or burnishing compound is better for some applications, but never use them on oxidized metal you wish to keep oxidized....eaves the oxidized metal a bit splotchy! Great for jumprings and findings with a bright-metal finish.

Comments for Pitted silver

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Feb 26, 2014
 Pitted silver
by: Novesart

Hi I have the same problem :( I've tried everything changed the soap lessened the water helped a tiny bit but I've tried so long I gave up please please if someone knows why or how I can fix this please please tell me :(!!!
Nove2000@hotmail.com
Apr 07, 2014
 Pitted Silver
by: Stacy

Sometimes if you've used too much solder and it has flowed over the surface of your piece, little pits in the solder become more visible when you put a high polish on the metal. I've been tumble-polishing metal for many years and I've never had clean blemish-free metal come out of my tumbler pitted. Can it be that perhaps the metal you're putting in is pitted, just not obviously so? Carefully examine the pieces under high powered magnification before tumbling to check the surface for pits and irregularities.

Often metal that has been melted, recast, melted again, etc. develops unsightly porosity (tiny surface pits and air pockets) in it. Perhaps you need to change the supplier you've been using. Just a guess here, but poorly cast metal could be a culprit. So can excess solder flow. Tumbling with stainless steel shot, water and dish soap does not pit metal.
May 29, 2014
 Pitted silver
by: Kirstin

I have the same problem- I put in perfectly polished piece apart from an area I could not get to with the polishing cloth and the entire thing came out pitted- not sure if I didn't leave it in long enough but it looks like it's been hit with a mini planishing hammer :-(
May 29, 2014
 Lortone Tumbler + 1 lb Stainless steel shot
by: Anonymous

I just purchased the Lortone 3A Tumbler machine and 1 lb stainless steel shot to clean my Pandora sterling silver charms and I tested the machine with dish detergent by putting in a sterling silver ring and just the Pandora bracelet for 15 minutes and took both out to see how it did. The ring band looked scratched and a little dented and no noticeable difference in the Pandora bracelet.

I am worried that if I put in other Pandora charms that it will damage them. I asked the Pandora store and they told me that they use a jewellery tumbler and stainless steel shots (same process) with their special cleaning compound to clean the bracelets.

Before I decide to return the Lortone Tumbler and shot mix, can you help me by telling me what is the right way to use the machine, without damaging the sterling silver? If you can shed some light on what the proper way to clean jewellery without dents or damage, then I will keep the Tumbler.
May 29, 2014
 Lortone Tumbler + 1 lb Stainless steel shot
by: Janet

Hi Stacy,
I just purchased the Lortone Tumbler 3A and 1 lb Shot mix and tested it by tumbling sterling silver rings and my Pandora bracelet (no charms on it) and found some dents/scratches on the rings and no difference in the shine for my Pandora bracelet.

I am concerned that tumbling in the machine will damage or ding my Pandora sterling silver charms? And I used dish soap. Will using burnishing compound have a better result?

Your advice or thoughts would be helpful.
May 30, 2014
 Answers to the above questions
by: Stacy Perry

Hello Kirstin, Anonymous and Janet! I wanted to address some of the concerns and questions you ladies have here.


To the author of the anonymous question.....I think you'll find the answers in the article I wrote about Tumble Polishing found in the Q&A section here. In addition to that information, please note that many Pandora and similar style charms and adornments have enameling on them which can be damaged tumble-polishing them. Maintaining their good looks with a jewelry polishing cloth for Sterling silver would probably work best.


As to Kirstin's and Janet's concerns about a rotary-style tumbler - in this case a Lortone 3A -one pound of Stainless steel shot (jewelry mix works very well), water and dish soap "scratching and denting" their silver pieces and making them appear to have had a hammer taken to them? I don't think so. I've been using tumblers for a very long time and I've NEVER seen that happen.


You may be seeing dents and scratches AFTER tumble-polishing because they were there BEFORE the metal became shiny - they just were not visible because the entire surface of the metal had a dull-ish finish caused by numerous scratches. Polish up the metal and hammered areas and deeper scratches become visible. Tumbling with stainless steel shot will not remove deep scratches, nor can it hammer texture metal. It also cannot pit the metal. Plating can get damaged or removed and surface blemishes can become more obvious when the light scratches, etc. are polished away, but the tumbler won't put them there.


I've said numerous times in the tumbling thread that tumble-polishing is not the be-all,end-all answer to our finishing prayers. Filing, sanding and buffing with different compounds using a buffing wheel or flexshaft are often a better way to create that high-polish shine or for removing more severe surface blemishes. Certainly not as easy, but well worth the extra effort! (a word of caution here......unless you are an experienced professional, DO NOT ATTEMPT TO POLISH CHAIN USING A BUFFING MACHINE!)


I would tumble a Pandora-style bracelet made of solid Sterling silver along with it's solid Sterling silver charms. But as the lampwork beads may not be annealed and often enamel is used to color the charms or they may have glued-on adornments, tumbling is not recommended!

I hope you ladies have better success with your tumbling and with the finishing of your jewelry items!



Jul 28, 2014
 Pitting
by: Binnsy

I just bought a barrel polisher and experienced pitting in the surface of the silver. Some items pitted more than,others but the pitting was evident on everything. It looked like a fine texture and because it was ubiquitous I couldn't accept it being on the silver prior to polishing. It seemed as though the shot in the barrel was just too fierce or rough. The barrel polisher I use in my college class polishes really differently and it's beautiful. I can only assume it's connected to the shot which in the college machine is much finer and has more varied shapes. I returned my polisher and will look around to find a polisher similar to the one my college uses.
Jul 28, 2014
 Pitting
by: Binnsy

I just bought a barrel polisher and experienced pitting in the surface of the silver. Some items pitted more than,others but the pitting was evident on everything. It looked like a fine texture and because it was ubiquitous I couldn't accept it being on the silver prior to polishing. It seemed as though the shot in the barrel was just too fierce or rough. The barrel polisher I use in my college class polishes really differently and it's beautiful. I can only assume it's connected to the shot which in the college machine is much finer and has more varied shapes. I returned my polisher and will look around to find a polisher similar to the one my college uses.
Sep 04, 2014
 Dry Rice!
by: Anonymous

After I tumble my things in stainless steel shot (to remove burrs, etc) I tumble everything from base metal to sterling to gold with dry rice in a rotary tumbler. The longer it tumbles the better the shine but 24 hours usually does it.
Dec 12, 2014
 pitted jewelry from tumbler..
by: Anonymous

I have been using a tumbler with steel shot and soap for years and never had a problem until recently. I put an 18 gauge polished pendant I made for a client. It was cut out with a small hand saw so I did NOT put a torch to it. I polished it and thought I'd throw it in the tumber for about 1.5 hours and it came out with dots all over it. pitted. I had to repolish it ... bummer! also the other day It happened again and I dont' know what I did different from other times UNLESS the pitting is there because I took it out to early, Maybe it has to be in longer? OR the metal is too thin? but then again it was 18 gauge. there has to be an answer!
Maria
Jan 07, 2015
 Pitted Metal
by: Stacy

Hi Maria!

Hmmmm.... I have never had a tumbler or the tumbling process pit the metal I put into it. Possible culprits are that the metal was pitted before you tumbled it and the high-polish surface enhanced the pits making them easier to see. It's possible the metal you're now using is of a lower quality and contains a lot of porosity. I've found metal qualities to change from supplier to supplier and even from shipment to shipment with the same vendor! Sometimes the alloy mix is bad and it's not obvious until you polish something.

If you use an echant and don't fully neutralize the silver or copper before tumbling, then residual etchant can damage items you add to the tumbler at a later date or even damage the stainless steel shot. You might want to give your tumbler and shot a baking soda bath and good rinse before tumbling anything else. Also, if you have any older metal you've successfully tumbled in the past, try it and see if you still have the porosity issue. This will help determine if it's perhaps just the batch of metal you're currently using.

Stacy :-)
Apr 25, 2015
 pitted silver
by: sil

Hi..I recently purchased a 5lb tumbler barrel bright and stainless steel shot and my bangles came out with tiny pits :-(...not sure what's going wrong?..I took the pins and any sharp ones out of my mixed shot and added balls to make up for the missing pins before I tumbled....any help would be really appreciated as I have adjusted shot soap and water quantity but still get the same pitted results.

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