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Sink trap for metal recovery


#1

Please help me here - don’t I remember that one of the members had a
cool sink trap that they made? I thought it was Jeffrey Herman of
Silversmithing.com. but I can’t find it. I did see one picture made
of typewriter letters, but I remember a picture of a bucket with a
high outlet. or am I dreaming?

Judy Hoch


#2

hey Judy… I have one I just packed up that I would sell. It is the
commercial one…$25 plus shipping…let me know.

Russ
Jewelry CAD Institute


#3

Judy,

I don’t know what you’ve seen before, but the arrangement my
employer uses seems to work. The sink drains, via a simple straight
down short pipe open at the bottom (no U trap) into a plastic trash
can. The can is covered, but the lid is perforated (and upside down
to act as a funnel) to allow liquid to drain through. Between the
sink’s drain pipe and the trash can, in that gap is a plastic tray
suspended on a wire bracket. The tray is some sort of generic office
paperwork tray, chosen because it has a solid bottom, but, after a
slight lip, the sides are a mesh. So water that drains down out of
the sink lands first in that tray. Any dropped small items (typically
stones that came loose in cleaning, etc) will be easily retrieved
from the tray, which is easily removed from it’s place under the
sink. Larger bits of metal stay there too. Most of what ends up
being recovered, the very fine stuff like polishing residues, flows
out of the tray into the trash can. The can has an outlet near the
top on the side, which then leads to the usual U trap and the sewer
line. Water with it’s carried valuable mud has time to settle out in
that trash can, so what goes out the side drain is pretty much just
water. The mud accumulates, and eventually gets collected and
refined. We have two of these systems. The one under a larger shop
sink where lots of things get washed, hands, etc, has two such trash
cans hooked up in series. Not much gets past it. This system also
allows us to rinse out things like casting investment mixing bowls
(most of the waste investment goes in an actual trash can before
going to the sink, but this way we can easily wash the bowls and
mixing tools out in the sink.) This does of course increase the bulk
of the trapped material, but it keeps the plumbing lines from being
clogged with the stuff. In the polishing room, where most of the
polishing and jewelry cleaning is done, there’s not enough room under
the small sink for a double system, so it’s just one small trash can.
Seems to work well enough. One refinement to that is that the outlet
drain, on the inside of the can, is fitted with an elbow fitting
pointing down, so water has to flow up into that drain. The opening
into that elbow is still high enough in the can, but decreases any
tendency for the water to move straight to the drain without having
time to settle out. One could, if desired, build an actual baffle
plate structure into this, but it hasn’t seemed to be needed. These
whole systems are made from simple hardware store plumbing fixtures
and Rubbermaid trash cans. Cheap and effective. The only downside is
that the system is not sealed from the air, so if you get some
fermentation or the like going on, the mud can get smelly. Avoid
washing food dishes and coffee cups in there to cut down on that. We
got some sort of industrial deodorant/disinfectant that gets added to
the tank now and then if odors become noticeable. Not sure what it
is. But I can tell you that the precious metal return from these
setups, every few years, is quite more than enough to justify the
fuss. Kind of amazing, actually…

Hope that helps
Peter


#4

Judy- Our sink trap is a plastic bucket under our sink with a pipe
going in and one coming out. An easy project to do and cheap. Have
fun and make lots of jewelry.

Jo haemer
www.timothywgren.com


#5

In my old shop I had a trap that fit your description, that I had
made from a 5 gal taping compound bucket, and PVC piping. Marginally
effective.

I know this is so, because I since have invested in the “Easy Trap
Miser” under sink system that I purchased form Stuller for under $60.
The amount of material captured by the Miser is vastly superior to
the system that I built myself, and unlike my homemade system, the
Miser is easy to quickly open, clean, and reassemble.

Earlier this week a small fancy yellow diamond in a customer’s ring
got blown out during a quick clean, and went down the sink. I was
able to recover and reset it in short order, because the trap system
uses both a screen and a settling tank.

I try not to think about how much money slipped away before we
decided to buy this trap system. Significant metal sludge, and
stones, small enough to pass threw both the stone basket, and the
sink screen are recovered to pay for the $60 investment every few
months.


#6

You can do as we faceters do, run your drain into a gallon jug
sitting inside a five gallon bucket. The heavy stuff stays in the
jug and the water overflows into the bucket. Once in a while I have
to empty the bucket but not too often.

For pottery use I cut the drain on my sink and let it drain into a
five gallon bucket, then hooked up the “downhill” side of the drain
to a hole cut high on the side of the bucket. (This was to avoid
pottery clay going into the drain.) It works fine but it’s kinda
awkward to empty it to get at what settles in the bucket.

John
Indiana