David,

Wow, yeah, the mechanical problem, I didn't even really consider that.  The
3.5 mm jacks I bought are really small and flimsy,  about 3/8" square little
thingy from Radio Shack, with a retaining nut that I can hardly fasten with
my fingers -- would need needle nose pliers to tighten.  Even worse I think
the height of the portion that should go through the dashboard is so
shallow, I might have to do something even more -- like glue a very thin
piece of metal to the back of the dashboard hold simply to provide a mount
for this jack.  And now I can just imagine one of my passengers (kids)
pulling on the cord, damaging the jack, or breaking off the plug.

Ok, thanks for all the ideas folks, I think I am going the route like Craig
used, just a male RCA to 3.5mm plug cable, off the shelf part, the RCA end
will be inside the dash, and the cable will just dangle out of the dashboard
somewhere.  Low mechanical risk, and really no downside compared to putting
a jack on the dash (except aesthetics).  Much flexibility on other concerns,
like I could tuck the Android in the glovebox under certain conditions.  A
six footer would allow the passenger to use the Droid for other purposes as
it is playing music.

Like I wrote to Craig about my real problem:  Anal-retentive engineer.
Definition:  they love Vanagons, and define complex problems in order to
undertake the challenge of seeking elegant solutions rather than redefining
the goal into a simple problem in the first place.

Roland

On Mon, Jan 31, 2011 at 2:08 PM, David Beierl <dbeierl@attglobal.net> wrote:

>
>  Personally for good mechanical strength I'd recommend using a pair of RCA
>> jacks in the dash.  1/8" phone jack is pretty fragile, and the plug is even
>> worse, although a right-angle head helps.
>>
>
> Or have your 1/8" jack on a pigtail with a grommet in the dash.  May not
> look as nice but it will keep on working a lot longer.  I try not to rigidly
> connect small phone (3.5/2.5 mm) to anything weighing more than a few
> ounces.
>
> Yours,
> David
>