[Tfug] CAT5 Cables, The Sequel

[Bexley Hall]

The Crimperama Saga
(subtitled:  How to waste an Evening without Trying)

Well, buoyed by all the positive suggestions, I
tackled the first of the CAT5 cables last night.

I spent some time googling part numbers to determine
what sorts of connector shells I had available.
Most turned out to be for solid wire :<  *But*,
one bag was clearly marked for *stranded* wire
so I was (cruelly!) encouraged.

Cut cable to length (plus fudge factor).  Carefully
removed jacket making sure not to damage insulation
on the individual conductors within.  Removed (foil)
shield and drain wire.

Separated all conductors and then, methodically,
removed 0.1" of insulation from the tip of each.
Reached over for soldering iron and (belatedly)
realized I was NOT making a "solder cup" but,
rather, an IDC cable.  <big frown>

Grab side cutters and effortlessly trim off the bare
portions of each conductor.

1st lesson learned:  do nothing when you are tired
(besides sleep, that is!).  Or, if you do, make sure
you remember what it is you have set out to do!!  :<

Sort the conductors into the correct order.  This
proves to be tricky -- the wires are small; stiff;
and the colors are very hard to distinguish!

2nd lesson learned:  work in a brightly lit room
and/or use a magnifying inspection lamp to see what
the hell you are doing!

Wires in shell, shell into crimping tool -- tah-dah!
First connector in place.  Gee, that wasn't too bad.

Proceed to other end of cable.  Foolishly assume
second connector will go on just as easily as the
first.  Wrong.  Getting the damn little things to
stay "sorted" in the right order proves to be
very difficult.  The portions of the wires that
extend out of the cable jacket are so short that
they tend to go where *they* want to go!  :<

3rd lesson learned:  use a pair of needle nose'
with padded jaws to gently hold the wires side by
side (or, grow smaller fingers!)

Second connector installed.  Optimistically run
cable around room -- behind equipment, under
tables, through ratsnest of other cables -- to
connect first machine in question to switch.

Naively power up the machine in question and
watch for the "link" light on the switch.  Hmmm...
I thought it would come on as soon as the machine
was powered up!?  No?  OK, wait until the machine
has completely booted just in case it has to
turn on the interface.

Crap!  Nothing.  Un-route cable so I can work on
it again.

4th lesson learned:  test cable before routing it!

Figure one or both connectors are not installed
properly.  Or, maybe a small nick in one conductor
that I didn't see.  Better safe than sorry -- just
replace both ends.

5th lesson learned: don't put away bag of connector
shells until you are SURE the cable works!

Reroute cable.  Turn on machine.  Crap!  Double-crap!

6th lesson learned:  see "4th lesson learned"  <:-(

Before unrouting cable, drag out voltmeter and
check cable for continuity.  Of course, contacts are
so small, need to use paper clips to have a small 
enough "probe tip" to be able to make contact with
them.

Grrrr... *none* of the conductors in the cable
appear to be working!  Suspecting crimps are not
"hard enough", recrimp both ends and retest.

Still nothing.  Cut off both connectors and examine
them closely.  LIkewise, examine first set to see
if there is something similarly "wrong" with those!
Double check order of conductors, etc.

Hmmm... maybe there is a slight difference in the
size of connector shell expected (by this crimper)
and the connector shells I actually *have*!  Or,
maybe the crimper needs adjustment?  It seems
*obvious* that the "teeth" on the connector's
contacts must not be adequately piercing the
insulation on the conductors.

Once again, remake the cable.  (third time's the
charm?).  Retest.  *Still* no good!  Something is
fishy here.

7th lesson learned:  paperclips are too large of
a diameter to reach the RECESSED contacts in the
connector body.

Replace paperclips with *pins* and recheck for 
continuity.  Gee, imagine that!  Cable is good!

Reroute cable since we *know* it is good.  Power
up machine.  *Still* no connectivity!  Crap!
Reboot.  Still nothing.

Double check cable seating in NIC and switch.  Both
look good.

Try a different port on switch.  Still nada.

Get annoyed. Cram connector firmly into machine's
NIC.  Hmmm... link LED on NIC comes on -- briefly.
"I wonder..."

After a bit more "persuasion", convince myself that
jack on NIC is flakey.  Intermittent contact.  Note
to self: replace NIC in that machine!

8th lesson learned:  see 1st lesson learned.  :<

So, aside from a serious bout of Homer-itis, this 
was a successful -- though lengthy -- undertaking.

Apparently, it *does* get easier with practice
since the cable I made this morning only took 10
minutes from start to finish...

But, for those of you who do this "routinely" in
your line of work, I extend heartfelt sympathies!
It's just too damn frustrating!  :>

Thanks, again, for the pointers!

--don


      ____________________________________________________________________________________
Be a better friend, newshound, and 
know-it-all with Yahoo! Mobile.  Try it now.  http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ