[GreenKeys] M15 with Frozen Dashpot

[Paul Birkel]

Thank you John.  I'm not "dreaming things" then :->.  I've successfully
followed your directions with the principal variance that I used Kroil
(on-hand) rather than Locktite freeze and release spray, applying several
drops several times around the piston shaft at the outer end.  I chucked a
piece of bar stock firmly into a vise and used that to get a firm purchase
on the flat-lip (not the correct designation, I'm sure) near the end of the
shaft.  And then exerted a steady firm pull until the shaft suddenly slid
along its range.  Then was able to remove and inspect.  Two different places
on the shaft were essentially "varnished".  After cleaning those, inspecting
the bore (clean!), and then checking the leather seal (looks and works fine)
I reassembled and lubricated using 5W-20 synthetic oil (on-hand).  Now
sliding smoothly and acting like a working dashpot :->!

Having set up a local loop I see that I've got another problem or two
somewhere involving the type-basket.  But at least the CAR RET works fine.
And the BELL too!

-----Original Message-----
From: greenkeys-bounces at mailman.qth.net
[mailto:greenkeys-bounces at mailman.qth.net] On Behalf Of John Nagle
Sent: Sunday, January 31, 2021 4:48 PM
To: greenkeys at mailman.qth.net
Subject: [GreenKeys] M15 with Frozen Dashpot

I've had that happen. Someone used a lubricant
with heavy fractions, and the light components evaporated leaving
the asphalt component behind. This is why I lubricate machines
with 0-20W synthetic motor oil, which has no heavy fractions.

It's reasonably easy to get the entire dashpot out. Then
remove the top, so you can get the piston out. The shaft
is probably stuck where it goes through the top.
That's metal to metal, so you can use Locktite freeze
and release spray. That shrinks the metal and opens
up enough space for its penetrating oil component to get in.

Once you get the piston moving, take it out and clean
the inside and outside of the piston shaft and hole of
whatever gunk was jamming the piston.

While you have the piston out, check the leather
seal on the dashpot. That's the only leather part
in a Teletype. I suggest lubricating that with
Hydrophane leather dressing, which is a silicone oil
used on horse tack. It won't evaporate and dry out.
(Incidentally, if you just paint that stuff on a
cheap leather jacket with a paintbrush,  in
a day or two the oil will disappear, the leather
will become nice and soft, and it will stay that
way for decades. Doesn't change the color, either.)

			John Nagle
______________________________________________________________
GreenKeys mailing list
Home: http://mailman.qth.net/mailman/listinfo/greenkeys
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:GreenKeys at mailman.qth.net

>>> Jordan Spencer Cunningham's GreenKeys Search Tool:
https://teletype.net/gksearch
>>> 2002-to-present greenkeys archive:
http://mailman.qth.net/pipermail/greenkeys/
>>> 1998-to-2001 greenkeys archive:
http://mailman.qth.net/archive/greenkeys/greenkeys.html
>>> Randy Guttery's 2001-to-2009 GreenKeys Search Tool:
http://comcents.com/tty/greenkeyssearch.html

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
Message delivered to pbirkel at gmail.com