Engineering properties of Delrin

[Craig Lebakken]

Steve B wrote:

Message: 10
From: "Buchholz, Steven" <Steven.Buchholz at kla-tencor.com>
To: "'qlist'" <quattro at audifans.com>
Cc: "'torsen'" <torsen at audifans.com>
Subject: Engineering properties of Delrin
Date: Tue, 4 Sep 2001 14:41:13 -0700

"I've been needing to build a transaxle mount adapter to
mate the subframe
mount setup from the 4000 transaxle to the "conventional"
mounting setup of
my '78 Fox.  I happened across a big chunk of Delrin that
may just fill the
bill for this application ... it is very light and there is
no need to worry
about corrosion.  The thing is I don't know the engineering
properties of
this material ... is there any reason that Delrin should not
be used for
this application?  Would Delrin have any problems with the
shear load that
will be placed upon it?  It looks like the stuff can be
threaded for
fasteners, but should I simply drill through and use a nut
and bolt to hold
everything together?  There will still be a rubber mount in
the system, so I
don't think there is too much to worry about coupling
vibration to the body
of the car ..."

TIA!
Steve Buchholz
San Jose, CA (USA)

Steve,

Consulting my Ryerson Plastics catalog I read the following
for the properties of Delrin (acetal), which is a Teflon
fluorocarbon fiber filled acetal homopolymer (can't tell you
much about that except what you can read into it!).
Applications are gears, bearings, bushings, pulleys, slide
plates, wear surfaces, chain guides and timing screws.

Relevant Material Properties are:

970000 psi tensile (yield)
1600000 psi compressive (yield)
380000 psi modulus of elasticity
200 F max. operating temp
Moderate resistance to organic solvents

Comparing this to steel...

Steel is 79X stiffer
Steel is 22.5 times stronger compressively
1/3 of the above for aluminum