Glad to see that somebody is interested in up-down accumulator coin
counters.  You run into nickel pianos without one now and then, and
they need something at least to count money.  That's what owners like
about them, but often they've been removed.  I'd think that it would be
a good product.

The problem of course is the mechanical escapement and those little
escapement wheels.  Finding an up/down Guardian relay in most places is
next to impossible, and people who work on pin ball machines and old
juke boxes aren't about to give away the coin mechanism for any price,
which renders the next machine that needs one worthless.

Nickel machines are making a comeback, and it's what people would love,
if they could find one (the machine, folks, not the nickel).  Irony is,
some idiot around these midwestern parts was busy removing the coin
boxes and put in a switch instead because coin boxes were too
complicated for him.  He understood "switches" -- or so he thought.
Often, you find the "guts" torn out of the original box and the
accumulator is gone.  After that, it's hilarious how they jury-rig
those boxes to trigger on a coin.

The Player Piano Co.'s accumulator worked pretty well for clean coinage,
but was a "stacker" thingy that didn't require an escapement.  However, 
I doubt that they make them anymore.  Besides, owners like the original
sound as it drops into the bottom box before the tune begins.

I was thinking of another kind of accumulator I could build that used a
"drop rod" and an escapement that "counts" on its grooves (like a big
bolt).  So the rod would be going up and down as nickels dropped.
Problem is, it still takes some machine work and I'm not so-equipped.
But if somebody with machine tools could visualize that little plan in
their head, they could see how it could work, right??

Spring-load the rod up, drive it down with a hinged pawl and let the
hinged escapement catch it each time, which it will do until the song
finishes.  That releases the escapement and the rod jumps up one notch.
The distance of a span is determined by the geometry of the escapement.
Better of course, would be the rotary escapement, but in lieu of the
little-old watchmaker, this would fill a need, as well as replace
several hundred PPCo's coin stackers, I'd think.

By the way, the escapement can be a pivot linkage operating two
linear motion rod pawls, so that when one is engaged, the other is
away.  That way, you don't have to build a punch and die to make a
one-piece escapement.  It's just a little 3 piece movement with a mount.

Craig Brougher