Hi There,
I am new to this forum, I was working on scenery on a friend’s layout the other day and was using sifted soil that he had collected a few years ago and we ran out. I remember seeing in a Model Railroader a guy divised a contraption that screened soil and the rocks that passed through a series of different size screens. That way he had varies grades of soils and rocks. Does this ring a bell to anyone?
THANKS
Seen in prototype, but never adapted for modeling purposes:
Rotary horizontal conical separator, fed from left.
Inner screen, coarse, conical with narrow end left, wide end right (and open except for supporting wheel spokes). Really big lumps fell out the open end at right, everything else passed through.
Outer screen, fine(r), conical with narrow end corresponding to wide end of coarse screen on right, wide end on left. Fines passed through, mid-size fell out to left.
These were in use to sort both coal and gravel a half century ago in Japan. The prototype screen was actually perforated metal plate. A miniature version with screen wire of two different sizes might make an interesting device - but you’d have to go into commercial production to justify the effort.
The easier way is to use rectangular screens of decreasingly fine coarseness - lots easier to make, much slower to use.