Mass finishing for the fledgling jeweler

Hi Orchid! I’m new here and have many questions but the most pressing at present is how the heck am I going to finish several hundred small charms that I got back from my caster in the “just cast” state? Let me say I love my caster - she has designed 7 CAD designs to my exact specifications and the end product is fabulous. With my first order I chose High Polish and was shocked when I got my bill and saw that they charged $12/piece for that process on top of the regular design/casting cost. (They are located in NYC so maybe that is a factor?) So with my next order I opted for just the basic cutting of the sprue, etc for $1.90/piece. How hard can it be to shine up a couple hundred charms?? So now that I own about every polishing wheel, disk, radial, compound, etc. I am spending literally days trying to get the same high shine that my caster gave! So do I… 1) bite the bullet and spend the $$, 2) find a cheaper casting company, or 3) is there some home mass polishing apparatus that I don’t know about? Many thanks for your thoughts!

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A quick search on this site finds this article…

If you search cleaning castings, a few posts pop up.

There’s also a book written bu Judy Hoch, Tumble Finishing For Handmade Jewelry: Mass Finishing On A Small Scale
I believe you have a vibratory tumbler in your future ; )

Pam

https://www.amazon.com/gp/product/B003TQJGWU/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B003TQJGWU&linkCode=as2&tag=ganoksincom-20&linkId=15c855059c402502f11df00e65cd11cb

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Thanks Pam! I’m on it! Melissa

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Melissa - Steve Alviti’s article is spot on, but a bit over the top for just getting into mass finishing. machines don’t need to cost that much, I’m running some tests on cheap vibratory ones from harbor Freight. Not great, but useful enough to see if you want to do this in your shop. Be aware that the Harbor Freight and cheap Loretone rubber barrels are round inside - that simply doesn’t work. You need to have flats inside to make the steel move. If you have questions, I’m happy to help. Post here and I’ll pm or email my contact information.
Judy Staby Hoch

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Let me put in a plug for Judy Hoch’s book on Mass Finishing. I have a copy, have read it and find it answers about every question you could have about mass finishing for the jewelry craftsperson. If you contemplate doing much mass finishing, the ways that Judy elaborates are the ones to go. Otto Frei has it for $12.50 at present. Maybe Judy will chime in if you can order it from her directly…

Hi Judy, yes I just finished reading Steve’s article…twice and am a little blurry-eyed! And I’ve spent to the whole day watching Youtube videos. My problem, I guess, is that my little business is too small for a big expensive system but there is no way I can finish/polish all the pieces I need to. Surely there is a happy medium. So yes I would love to hear more about your tests runs!

Many thanks!

Melissa

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Hi Judy, yes I just finished reading Steve’s article…twice and am a little blurry-eyed! And I’ve spent to the whole day watching Youtube videos. My problem, I guess, is that my little business is too small for a big expensive system but there is no way I can finish/polish all the pieces I need to. Surely there is a happy medium. So yes I would love to hear more about your tests runs!

Many thanks!

Melissa

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Thank you!!

I just bought a tumbler. It’s a Lortone Jewelry Tumbler 4lb capacity. The white plastic drum won’t discolor metal. There will be 2 lbs of stainless steel media and a drop of dawn dish soap. This burnishing action will give a gloss to my pieces. Not supposed to have to hand polish. The tumbler arrived this morning but the media is a couple weeks out. Can’t wait!:heart:

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Buy Judy’s book and study it cover to cover. That being said, I have made small batches of silver jewelry for 47 years and my go to for finishing is rubber abrasive wheels first and then tripoli and rouge. There are other compounds that are cleaner, but I like tripoli and rouge. When I was on the craft show circuit and making a lot of the same thing, I bought into vibratory tumbling. It works, but I still need to see the traditional tripoli and rouge finish on my bigger pieces. Stainless steel shot works well for small pieces as long as you get a decent tumbler with a good barrel with flat edges inside. Judy covers all of this in her book. You need to design and fabricate with finishing in mind. You might start by asking your caster how they finished the pieces that you paid to have finished. If you were happy with the results, replicate the process in your own shop. I spend a lot more time finishing most of my work than I do making it. I spend even more time documenting, packaging, selling, shipping and showing it on my website than I do either making or finishing it. That is another story. Good luck…Rob

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Rob thank you very much!! I am still so new to this business that I don’t know what I don’t know…yet. I did email my caster today…we’ll see what she says…? Your advice makes me feel better and yes I am ordering Judy’s book now!
Cheers! Melissa

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Thank you!! Yes they are pretty cool gadgets and can def lessen the workload!!
Melissa

Greetings Melissa,

I have used several types of tumblers to various degrees of success. But none of them have ever given my the final look that hands on work at the wheel supplies. I have said before that my Dad always felt the piece wasn’t finished until it was polished. For me and my products that means a wheel with tripoli and rouge.

I use my tumblers for knocking down the sharp edges and cleaning newly made work after it comes out of the pickle. Ceramic gum drops do the best for me in my process. But the finish that folks see in the store or at the craft and art show comes from a wheel. When I get back from a show, or a few shows, I may toss the metal into the tumbler to clean the surfaces and a quick wipe down with a Blitz cloth puts on shine for the next show. The customer may buy the art but the first thing they see is the shine.

Surprisingly the best result I get from my tumbler is in rounding off the ends of ear wires. But as a cleaning and touch up tool it is indispensable to me.

For Judy’s research I bought a big Harbor Freight Vibratory Black Donut when my 25 year old Vigor Tumbler burned up its motor. I am not unhappy with it for the purpose for which it is used. But it is very noisy because the tub is thinner than Thumlers or Raytec. Additionally the tub degrades and leaves a black residue unless the water is soapy and flows through well.

Don Meixner

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Don thanks so much for those words of wisdom. Sounds like a tumbler may be a great starting point and at least greatly reduce my finishing time! I feel like I can rest a little easier knowing that there isn’t a magic machine out there that I hadn’t discovered…just elbow grease. I am def going to read Judy’s book then check out some tumblers.
Nice to see the sun in Central KY today…stay well!
Melissa

You haven’t really talked about the size of the charms, how intricate they are, concerns about detail being worn away due to abrasives, etc.

If they are just clipped off the sprues, you will probably need to grind off the sprue nubs. Depending on the size of the sprue and the size of the charm, a bench grinder/sander is the fastest way to remove material, but you will need to be careful about capturing the grindings if you want to recycle them.

I’m a fan of magnetic tumbling. Prices vary based on the size of the container which will dictate how many pieces you can tumble at the same time. If you can afford to work on your charms in batches, you can find a happy medium between price and capacity.

Final polishing on a wheel will take a fixed amount of time per charm.

So, if you total up all the equipment you need to buy and the time spent per charm (time is money remember!), evaluate that against the cost your casting house charges per piece along with your selling price and how quickly you can sell your charms and see if you would still break even or not.

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Hi there! Yes all very good points! My charms are on average about ¾" x ⅜" and not terribly detailed with the exception of small logos recessed into the fronts. That could be an issue with agressive polishing. They are cast in Sterling and red brass. I DO have them clipped off the sprues and ground flat - I don’t mind paying that fee. There are small recessed areas that I just can’t seem to bring to a high shine - not like my caster can. I’m still waiting to hear back from her btw. So yes, I think this may be a math issue…how much is my time worth and does it amount to what they charge to give a perfectly polished shine.
Thanks so much for your thoughts!!

So the magnetic tumbler does excel in getting into the little nooks and cranies due to the small size of the stainless steel pins used to create the burnishing action. Larger shot and ceramic media will have a harder time getting into some of those tight spaces.

I have a Best Built Super Mini 90 that I bought from Otto Frei about 4-5 years ago that I use with every project. It can hold about 5-6 rings and does a pretty good job of brightening up my pieces. If you use something too large or too heavy in this small unit, it will not be able to tumble around and the only places that get burnished are the areas exposed to the moving pins.

These small units go for anywhere between $250 to $300, but for me it has been a worthwhile investment.

The magnetic tumbler will give you a shine in those recessed areas, but unless you can get a polisher into those small spaces, you might see some orange peel texture. If it is small enough thought, it would be hard to notice without a loupe and you might be okay with the results.

My caster does a magnetic pin polishing as part of his fee, and it’s a good start. Some pieces take more finishing than others, and some have a lot of pre-polishing to do. I use 3M radial bristle discs on my bench polisher, from yellow through light green. At this point I’ll do any necessary blackening of recessed areas and put them in a rotary tumbler with assorted stainless steel shot and tumbling soap overnight. Take them out, wash them well, and do any touch up needed. I’ll end up with a sunshine wheel on the bench polisher.

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I’m going to check that out! Thanks so much!!

Katheryne Sharp - to get optimum results from your new rotary tumbler, get a proper compound for lubrication. using a drop of Dawn just isn’t the best you can do. You paid for nice equipment and media, don’t cheap out on the liquid.
Judy H

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