Years ago I worked for a major New England machine chain factory.
The company always tumbled chains of every size including the
thinnest neck chains. The method was very simple. They built
metal (usually brass) racks consisting of two disks slightly
smaller in diameter than their barrels. These were joined
together by four or five round bars. The bars were slightly
shorter than the length of the barrel. The two disks were drilled
with four or five equidistant holes about 1/2 inch (12 mm) in
from the edge. The holes were sized so the bars would slip fit
into them. The bars were then brazed into the holes with their
ends flush with the outer surfaces of the disks. To tumble any
chain of any length securely tie the first link to one of the
bars using about a 20 ga. copper wire. Wind the chain around the
rack and secure the last link. Do not overlap any area. The chain
should be fairly taut. As with any tumbling, proper media
selection is extremely important. Your steel shot must not be
able to lodge in any openings. If your design is a very open one
and you want to burnish the inside of openings, make certain that
the shot will pass through freely. If the shot is too large, it
will not get into corners. Place the chain on its rack into the
tumbler and relax. As long as the chain and/or wire don’t break,
it will not knot or kink. Good luck. Ray Grossman Ray Grossman Inc.