On Mon, 4 Jun 2012 13:49:52 -0700 (PDT), Peter Easthope
wrote:
2012-05-25 Jeff Liebermann wrote,
Brass plate? All the Panasonic print heads I've seen have a plastic
guide block. Care to disclose the model number?
Panasonic KX-P1180 Multi-Mode Printer.
Egads, an antique. I haven't had to deal with one of those for
at least 10 years. I prefer Okidata anyway.
http://www.ebay.com/itm/200755930602
$19 seems a bit much. I may have one in my pile. I may also have an
original manual.
The frame which holds the guide
plate is black plastic. Certainly the plate is brass. Might photograph
the next one I overhaul.
https://www.google.com/search?tbm=isch&q=KX-P1180+print+head
http://www.recycledgoods.com/zoom.aspx?productID=15780
What brass?
After soaking with isopropanol and with WD-40, still no sign of
the frozen pins working free. I lifted out the 7 free pins.
Then put the tip of a slender straight blade screwdriver under
the lever of pin 8. A gentle twist and pry broke the tip of the
pin free. Likewise for pin 9. I cleaned the pins with an old
Scotch-brite type scouring pad. For interest, put a pin under a
low power binocular microscope. The striking end is pitted with
corrosion.
Careful. If one of the pin fails to retract, it will shred the ribbon
when the ribbon tries to move. A pitted pin isn't going to help, as
it's going to attract crud into the pits, and eventually jam (again).
Oui..Definitely not a good design. Did this result from inexperience
of the designer or from intention?
The 9 pin print heads were the first generation. Well, actually,
there were 8 pin heads on the original Epson FX-80 and Centronics
printers. When they went to 18 and 24 pin print heads, things really
became marginal. Smaller and stiffer wires tend to wear out the
plastic guide plate. The idea was to keep the movable mass to a
minimum, which allowed higher print speeds. Also, there was plenty of
heat build up. I don't think any of the heads were meant to be
repaired or rebuilt. However, they were made to be cleaned and
lubricated regularly. That's what the felt pad is for. Soak it with
oil.
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
#
http://802.11junk.com
# http://www.LearnByDestroying.com AE6KS