I received an email from James Cantrell about washing the cloth bag
type filters used in Handler and similar efficient collection
systems. I include part of my early morning reply below. I
contacted the head jeweler at my former place of employment and
asked how he washed the filters. His reply: We don’t. I shake
them down and vacuum. He did mention two local companies who use
cartridge type collection systems and said the systems work well for
those folks. One is a purchased brand and the other is “home made”,
using both fiberglass prefilters and a cartridge type final filter.
In wood work, I have found the small cartridge filters for shop
vacuums made by Gortex work extremely well and are easily cleaned.
Apparently, the home brew system used prefilters combined with
filters similar to the Gortex but larger and likely not washable.
Cleaning is reported to be easy, if still a bit messy. The advantage
is the prefilters are burnable for refining, easily changed and
inexpensive. The final fiters may be tapped and washed or replaced
at a slightly higher cost.
Here is some of what I said to James, showing some disgust about the
cloth filter bags:
(re:washing cloth filters) "Really, the answer is not a satisfactory
one and there must be a better way! I mentioned hand washing in a
large container, like a plastic garbage can. The idea of the
garbage can is to catch all the sludge for possible refining later,
though after a good vacuuming I seriously doubt any sludge would
come near the cost of a new set of filter bags or even pay for the
time spent washing.
I don’t know a time efficient way to wash these things. If I had
to do it now, I would likely take the bags home, scrub a little and
hose them down in the driveway! The metal insert is removable in
the set we had so at least that helps a little in washing. Still,
it is drudgery. : )" End of email.
So, there it is from me. I am looking to upgrade to cartridge
(canister) type collection if the sound is not oppressive.
Certainly, the effectiveness of the system would be acceptable if
crud on the filter media does not lessen air flow dramatically. I
learned this from wood work dust collection and this vital point was
mentioned by Ken: Does the system keep on keeping on once dust has
collected on the filters.
Does anyone else have any suggestions for an efficient, relatively
easy to clean system with acceptable sound levels’ This is a two
pronged issue: Health and Recovery of Precious Metal.
I must say, the Handler (cloth bag) system I formerly used was paid
by refining recovery within 1 1/2 years. That is not bad considering
the system cost nearly $2000 several years ago.