"Tight" pancakes

In my continuing (futile?) efforts to diagnose performance problems
with carts, I decided to try varying the winding tension on the reel
of a noticeably stiff late Audiopak to 1.) prevent jams, which had
obviously taken place on this particular cart, a troublesome "double
album" one) and see if there was a "rule of thumb" I could devise that
would serve as a guideline for future repairs.

Although this particular cart ("Yesshows"...no biggie) was operating
when I got it and after installation of a Win-Gib® and the usual
cleaning and application of PTFE, it was noticeably "stiff" when
running the tape around manually, which I usually do by using a the
eraser end of a pencil on the center of the casting. Tape "peel off"
seemed stiff and begging for a hub jam, the #1 killer of cartridge
tapes. I had removed the pancake and had cleaned the reel, something
I do with most carts with a closed reel table, but it didn't help on
this one. When I replaced the splice, I notice that taking up any
further tension from the pancake would cause the tape to "squeal" a
little bit...I could feel the "stiction" of the tape binding against
itself as I took up more tension. Knowing everything was as pristine
as possible, I decided to loosen the tension on the pancake by moving
the outer edge clockwise (looking down on it) with a pencil eraser.
After giving it about three turns, I again pulled on the end, and the
squeal was gone. Pulling about to where the tape was originally
caused it to start again. So, I back it back up another turn to where
the squeal just went away, made the splice, and then ran up the slack,
about another turn's worth. Now, when I ran the tape around manually,
the tape, after redistributing the tension in the pancake, came out of
the center hub almost effortlessly and there was far less drag on the
guides, but no discernable slack while the tape was in motion.

Slapping the cart back together, I popped it into the 8075 for a test
listen...perfect! No more flutter, and the cart was nice and quiet,
which is wasn't before. Out into the Paragoric car player, same
thing...ran as well as the best of them. Thus, this is my new "rule
of thumb" for tape tension...take up the slack on the pancake until it
squeals, and then back off 2 or 3 turns on a ¼ mil tape (like most
"double albums" and 90 minute carts) or maybe 1 turn on a ½ mil tape,
as found in most 10-12 minute/track tapes and 45 minute blanks.

Another technique I've adopted is no longer completely scraping and
cleaning clumped up graphite off of the guides. It seems instinctive
to me, after years of dealing with profession RTR machines, to clean
the entire tape path before each serious usage, but I got to thinking
that the graphite left behind is slicker than plastic, and should make
the tape move more easily. Problem is, most times deposits of
graphite and other back coating material is seldem if ever even; it
usually is found on guides and hubs in clumps and is usually unevenly
distributed on the guide. So now, I scrape off obvious clumps and
uneven buildup while trying to leave the guide uniformly "black" in
color. For most carts that have a mistracking problem, I've found
without fail that the leading guide going to the contact block has
crap built up on it, thus setting the tape up for a misaligned run
across there and into the head guide. Cleaning that up always
eliminates the problem. If the surface of deposited graphite appears
to be flaking off of the guide in spots, I'll take a piece of
burnishing cloth and try to evenly distribute it across the contact
area of the guide. So far, this method has worked some wonders with
"problem" carts, especially those which have a tendency not to track
properly. It even tends to get rid of a lot of small flutter problems
in carts prone to that, like later TC8s, which I've had speed
headaches with from Day 1. I used to religiously remove any trace of
graphite from everything inside the cart. No longer, but I do still
scrupulously clean both the pinch roller and the reel hub, on which
can usually be found lots of crumbs of back coating and dirt.

Anyway, there's today's tech post! Enjoy.

dB

Is there a way to fix a very tightly-wound (practically immobile,
crinkling up any tape pulled out from the center when forced to do so
by hand) tape without completely unwinding the tape and winding it back
on the spool again (that would be a nightmare) or using the solution
presented by the 8-track FAQ, which (I believe) involves cutting the
tape and splicing it together again?