Pumice powder

Hello! Back in mid-late March (before I was on the Orchid list) there
was a discussion regarding the tiny burs on the jump rings made on
the Jump Ringer. Pauline suggested that one could tumble the jump
rings in a rotary tumbler with some pumice for a couple of hours; Ray
suggested that a ratio of two parts pumice to one part work, tumbled
dry 24 hours a day for a week would be good.

I’d like to try tumbling my Jump Ringer-made jump rings in pumice,
but when I went looking for the pumice, I ran into a couple of
issues. When I looked in my Frei & Borel catalog, I found that they
carry three different grades of pumice powder – Medium (80 mesh),
Fine (150 mesh), and Flour (200 mesh). Then when I looked into Rio
Grande’s catalog I found that they carry one grade only, and it’s
described as 320 “grit”.

Two questions:

  1. Is “grit” the same as “mesh”?

  2. What mesh(s)/grit(s) would be good to use to tumble off those tiny
    jump ring burs?

It would be nice to buy the pumice in the 1-lb. quantity that Frei &
Borel carries rather than Rio’s 5-lb box, but if what I really need
is the Rio Grande stuff, or all four different grades, or yet another
grade or grades, please let me know.

This will be my first adventure in tumbling/mass finishing! I will
be purchasing a small rotary tumbler for this project as well, so …
any words-of-wisdom regarding Lortone vs. Thumbler’s (for example)
would be greatly appreciated. (I’ll be getting a Lortine 3A unless
I’m talked into something else.)

Thanks in advance!

– Constance

Attn. Constance

  1. Pumice powder grit to remove the bur on a jump ring should be
    Medium I would say about 150 should be good. Fine and Flour will take
    a long time and they are good for polishing/finishing.

  2. Tumbler I would go for the Thumbler as it is better has a steel
    outer with rubber lining. Get the bigger size 15 LB capacity.

1 LB Pumice powder is for $5.50 & the tumbler 15 LB capacity is for
$159.00 shipping will be about $15.00 total cost will be $179.50. You
may call & place the order or just E-mail The phone # is 800 221 4812
and do mention Orchid.

I hope this will help you.


Hi Constance, As a side note, you can probably buy pumice powder a lot
more readily and inexpensively at a local hardware store. It may not
be as uniformly graded as what you would get from a jewelry supplier,
but I’ve never noticed any deficiency.

All the best,

Dave Sebaste