I purchased an inexpensive vibratory tumbler from Harbor Freight to experiment with dry polishing with walnut shell. the finished product was very sad! The pieces were all dinged up and I had to re-sand all of them.
I am guessing that the rough interior surface of the tumbling bowl imprinted on the pieces - and possibly the bowl was over loaded.
I am wondering if my problem is the cheap tumbler or if this method of processing always results in a few dings
Do the Ray tech tumbler have bowls with smooth interiors.
I would love to get some suggestions on how to make this finishing method work better!
I don’t think that the rough surface of the bowl could imprint on your pieces. What’s most likely is that you overloaded the machine. Typically the media should be 85% of the volume and the pieces 10 to 15%. The walnut shell needs to be charge with a polishing compound.
However - there is no way i know to get a nice finish with only using dry media. Did you run a cut-down step and then a prefinish step? If you are going for a nice shine, you would run a burnishing process following those two and then run the dry media.
As to cheap tumblers - I find they are cheap because they are not durable. so far, I mostly haven’t seen them damage jewelry.
Judy Hoch
I do several cut down steps prior to the walnut finish. It is good news about the bowl, I wasn’t enjoying the idea of having wasted my money. I will try again with fewer pieces - in fact I have some to test on today!
I have tried to get the book on mass finishing on several occasions but it always seems out of stock. I wish it could be published digitally.