GotTheBug,
Since I haven't personally processed any of these chips yet, I'm limited to either parroting what I've
read here on the GRF, sharing what my research has found, or firing off some semi-informed opinions.
Having read and reread patnor1011's process, it is clear that the incinerated chips do need to be broken up or
ground up-------------it looks like incinerating first to reduce the material volume and increase
access to the Au is a really good idea.
From all of the chain flail mills I have looked at on ebay, they seem to share 1 thing in common, and that
is they operate at around 1500 rpm, and could care less what you feed into them.
By contrast, the Action Mining hammer mills run at 3000 rpm, and from the test pictures I've seen, they
produce a finer mesh of dust on the 1st pass than does a 1500 rpm flail mill; however, the carbide hammer
heads will chip or break if they hit a certain amount of metal, so you've got to be careful what you jam in
them (I know one guy who was demonstrating his large mill to a prospective buyer, and a rock got jammed
in the feed hole, and the buyer goofed up when using a screwdriver to dislodge the rock, and broke one of
the 4 hammers).
EDIT: Just to make certain I'm not misrepresenting the quality of Action Mining hammer mills, the screwdriver
incident was a dumb, flukey thing; their mills are designed for one thing, and that is grinding chunks of hard
rock ore .5" or smaller. I called them a while back and asked if their smaller mill would grind I.C. chips; the
owner said "no". But, by contrast, the ebay seller RockyMountainGold said he used to grind I.C. chips in his,
with no troubles at all. I intend to acquire one of the small mills in the near future, and will post the results
of my testing here on the forum.
So, with your rig operating at 3450 rpm, and capable of accepting just about anything you could stuff into it
because it's a flail mill,it would be very interesting to see what mesh size you would get on the 1st pass.
I, for one, would be very interested in your results.
Cheers,
Mike
on the first pass