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Richard J Kinch
 
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Default New Chinese mill vs old high quality mill

jim rozen writes:

Another reason to stay away from pure teflon is, it is very
tough to bond it using any regular adhesives.


You can't be referring to the MSC item I cited, which is treated on one
face to be bondable with ordinary epoxy.

My best guess would be to use teflon-loaded delrin
available inexpensively from mcmcaster carr. It will
exhibit pretty much the same slide characteristics
as pure teflon, but will not cold flow.


Delrin (trademark for acetal, capitals, likewise Teflon for PTFE) AF
(presumably abbreviation for "anti-friction", namely acetal with PTFE
component) does improve the structural properties, and comes close to pure
PTFE for dynamic friction, but does not come close to pure PTFE for the
static friction ("stiction"). Getting down around 0.04 static COF would
seem to be a huge improvement for CNC movements like tangents of curves
that have minimal motion in one axis vs another, where stiction causes
staircasing. From what I read this is what many CNC machine ways use for
just that purpose.