[GreenKeys] grunting 28 KSR?

[Richard M. Gillingham]

How could I have forgotten the wrench?!..  It's the perfect thickness to 
adjust the clutches.  It's been too long since I've done it, I guess.

I had an RO catch fire once.  One of the screws on I don't remember which 
clutch had come loose, and the other sheared.  Melted clutch and oil soaked 
wicks.  Poof.  The only '28 I ever saw fail in service at the FAA.

Thanks George.

Gil, W1RG


----- Original Message ----- 
From: "George B. Hutchison" <w7tty at readysetsurf.com>
To: "Eugene Hertz" <ehertz at tcaf.org>; <greenkeys at mailman.qth.net>
Sent: Saturday, June 03, 2006 3:39 AM
Subject: Re: [GreenKeys] grunting 28 KSR?


> Gene and GreenKeyers - - -
>
> Gil has the closest call when it comes to the "grunting" in the
> machine.
>
> The model 28 clutches have to be latched after every rotation in
> order to not damage, or in extreme cases, fry the clutch drums and
> shoes.
>
> The clutches all must have sufficient inertia when the clutch stop
> comes around to disengage the clutch. If the clutch is not spinning
> fast enough, typically 60 WPM is where the problem will most often
> occur, then when the stop latch attempts to complete the
> disengagement it does not have enough oomph to successfully latch up,
> and the clutch will drag, sometimes giving a zizz-zizz-zizz sound, or
> a sort of moan when it does not completely disengage.
>
> The clutches are not that hard to adjust, but it is almost vital to
> have a J1 wrench to get it right.
>
> The ideal distance between the clutch stop lever and the clutch latch
> with the clutch engaged is about the thickness of a J1 wrench. The J1
> is also just the right tool to get into the gap between the clutch
> body and the clutch drum so as to be able to loosen the two 3/16"
> screws which allow adjustment of the clutch.
>
> Too wide a gap between the clutch stop and the latch will permit the
> possibility of the clutch stop lever falling between the stop and the
> latch, causing things to sometimes come to a screeching halt, with
> sounds and smells akin to a fire in an oil refinery. The clutches can
> get so hot that they will turn black, and the hardness of the clutch
> shoes and the drum will just go away, making replacement of the
> entrire clutch and drum mandatory.
>
> I believe the Bell System Adjustment book on RTTY.com has some clutch
> adjustment info.
>
> The motor problem sounds like either the motor start capacitor has
> failed or the motor start relay is  defective. These items reside in
> the square housing underneath the motor. Easiest solution is to
> replace the motor with a known good one.
>
> 73,
>
> George - W7TTY
>
>
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