[ Bill Chapman wrote in 150920 MMDigest:

> I am attempting to correct an Ampico intensity pneumatic that will
> not lock in the 'on' position as it is supposed to.

There was an excellent web page that was online a couple of years ago,
with many photos and a well-written discussion about various aspects
of Ampico rebuilding.  I cannot find that page now, or tell you the
name of the rebuilder; perhaps someone else can advise.

One of the suggestions was to replace the thick felt punchings used as
valve seats under the lock-and-cancel valves with buckskin punchings
of similar size.  These punchings are intentionally porous, to allow a
certain amount of airflow (so that a 2, 4, or 6 intensity perforation
will override a simultaneous cancel perforation, maybe?).  But the
buckskin allows a little less air to pass through, which makes the
valve lock a little more positively.

I had a difficult time getting the intensity levels to lock in place
until I tried the buckskin; it works perfectly now.

Bill Luecht - in humid-dry-humid-dry Indiana

 [ Paul Manganaro has several web pages about the Ampico A, visit
 [ http://antiquemechanicalrestorations.com/Ampico_A.html  -- Robbie