On Mon, 22 Sep 2014 04:01:33 -1000, "John Keiser"
wrote:

Any clever idea as to what design criteria dictated use of this grade nylon?

Lowest bid supplier?

Supposedly, Nylon tends to yellow with age but not lose any of its
strength. Indoor use and being inside a box eliminates UV exposure
and dehydration as possible culprits. Another bad guess(tm) might be
that the Nylon was attacked by solvents in the lubricating grease, but
it's difficult to imagine that the little grease inside the timer
would do much damage. Nylon can be depolymerized with steam in the
presence of assorted catalysts (used in recycling plastics), but
that's also unlikely. Yellowing in Nylon can be caused by UV
exposure, which is also unlikely.

Lacking any additional forms of attack, I think we can safely default
to the Nylon having been improperly prepared or molded, and having
destroyed itself. In other words, I have no idea exactly what
happened.

No recall notices on the TN711:
http://www.intermatic.com/en/CustomerSupport/ProductRecalls.aspx
You might be able to get a replacement timer by contacting Intermatic,
but methinks a digital timer might be a better replacement.

Useless, but interesting items found while Googling:

Method for restoring whiteness to yellowed nylon fabrics
http://www.google.com/patents/US2830868

Retr0bright (which doesn't work on nylon but works well with ABS):
http://retr0bright.wikispaces.com/

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558