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<font size=3>The pressure devices and constructed of 3/4" PVC pipe,
end cap, spring and a wooden dowel.<br><br>
The dowel is a spring-loaded plunger whose length is determined by the
depth of the rim and the<br>
amount of pressure you want to induce. Alternatively, I have discovered
that a 3/8" threaded rod<br>
with a nut effects a more easily adjustable plunger, the rod fits inside
the colis and the nut is a<br>
collar to adjust length/tension.<br><br>
Another execution is PVC pipe with a nut and bolt. But I like the
self-compensating aspect of the<br>
spring-loaded plungers when multiple applications are involved.<br><br>
<br>
Jon Page</font></body>
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