Possible "Ball Bleed" replica project

I have noticed of late, some discussion here and elsewhere about Ampico
ball bleeds and their relative unavailability. Hickman's patent for these
(or the entire valve unit of which the bleeds are a part) is #1,800,796,
issued in 1931 (but was filed in 1927. If there is another patent that
covers the bleed device itself, I could not find it.

Be that as it may, the patent, while long on description, is short on
specific dimensions of the bleed, as might be expected, so replicating
it requires some reverse engineering. The outer dimensions are relatively
easy to measure, and the 1929 Service Manual provides most of the
remaining details.

The fixed bleed is specified as a #70 drill. The (bottom) hole of the
ball unit is given as a #60 drill, although my measurement of several
original units is closer to a #61 drill. The difference, only 0.001",
is probably within normal manufacturing tolerances. The diameter of the
ball, while not given in the manual, measures, from a disassembled unit,
0.093", or nominally 3/32".

Not specified, and not easily measured, is the distance the ball actually
travels within the unit. This may be significant in the valve's proper
operation because of the speed with which the ball rises and falls. Does
anyone know of an analysis that has determined this parameter?

Thanks in advance,
John Grant

 [ The Ampico B Ball Unit Valve assembly is illustrated and described
 [ at https://www.mmdigest.com/Gallery/Tech/Ampico/amp34.htm -- Robbie