Subject: Re: [sloan-25mlog 4270] 2.5m obslog 20181113 (SJD 58436)
From: John Downey
Date: Wed, 14 Nov 2018 10:33:07 -0700
>=20
> The pluggers reported having trouble slewing the telescope today for =
afternoon
> checkout. Unless I am mistaken, the telescope would start to slew but =
then the
> brakes would suddenly come on and hault the slew to instrument change. =
They
> power cycled the wind baffle knife switch and the amplifiers. This =
solved the
> problem. They noticed that the knife switch felt a little different =
switching it
> on and off, more fluid than usual, as if something was not catching =
right. I
> verified that the power switch is not catching and turning on like it =
should. It
> took a couple of cycles for the LED to turn on. JohnD was notified and =
he will
> investigate the switch tomorrow.=20
When this happened before, 2016 I think, it was also a very cold day.  =
James looked at the switch, and we think the problem is from age and =
stiff lubricant (these kinds of mechanisms are not heavily lubricated).  =
He applied a little oil that is thin enough to wick into the bushings =
and not be affected by the cold.  I may add this to the shutdown list.
John=