knock on direction reversal #Guiding


Peter Santangeli
 


Yup. I get that. I just hit this noise situation after adjusting the worms for backlash.

I think I figured it out though. The worm adjustment was too tight. When I loosened it up a bit (by turning the spur with the worm lock slightly loosened) the noise went away.

pete


On Tue, Jun 7, 2022 at 6:34 PM Roland Christen via groups.io <chris1011=aol.com@groups.io> wrote:
Guiding and slewing are two different things. When slewing back and forth, the RA motor does reverse direction. But that has zero to do with guiding.

When guiding, the RA motor simply slows down or speeds up slightly, which in turn causes the guide star to move either forward or backward on the crosshair. Guiding never reverses the RA motor. Guiding is never done at slew speeds.

Roland


-----Original Message-----
From: Peter Santangeli <peter@...>
To: main@ap-gto.groups.io
Sent: Tue, Jun 7, 2022 7:42 pm
Subject: [ap-gto] knock on direction reversal #Guiding

I've been trying to isolate some issues guiding my C11 on AP900 that look like might be backlash (strangely... in RA).

I just re-seated my RA worm (I did this 5 or so years ago). 

I just noticed that when I reverse directions at maximum slewing speed, there is a significant sounding 'knock' from the gear box. I don't remember this before, but maybe I'm just paranoid. 

Should this be quiet or is a noise on reversal ok?

pete

--
Roland Christen
Astro-Physics


 

Hi Pete

I don't have an answer for you on the knock sound, but generally backlash is not an issue when guiding in RA. it's tracking in sidereal, so the axis will slow down or speed up in response to guide commands, but never reverse.

If you have a guidelog that may shed more light on your problem?

Brian


On Tue, Jun 7, 2022 at 5:42 PM Peter Santangeli <peter@...> wrote:
I've been trying to isolate some issues guiding my C11 on AP900 that look like might be backlash (strangely... in RA).

I just re-seated my RA worm (I did this 5 or so years ago). 

I just noticed that when I reverse directions at maximum slewing speed, there is a significant sounding 'knock' from the gear box. I don't remember this before, but maybe I'm just paranoid. 

Should this be quiet or is a noise on reversal ok?

pete




Roland Christen
 

Guiding and slewing are two different things. When slewing back and forth, the RA motor does reverse direction. But that has zero to do with guiding.

When guiding, the RA motor simply slows down or speeds up slightly, which in turn causes the guide star to move either forward or backward on the crosshair. Guiding never reverses the RA motor. Guiding is never done at slew speeds.

Roland


-----Original Message-----
From: Peter Santangeli <peter@...>
To: main@ap-gto.groups.io
Sent: Tue, Jun 7, 2022 7:42 pm
Subject: [ap-gto] knock on direction reversal #Guiding

I've been trying to isolate some issues guiding my C11 on AP900 that look like might be backlash (strangely... in RA).

I just re-seated my RA worm (I did this 5 or so years ago). 

I just noticed that when I reverse directions at maximum slewing speed, there is a significant sounding 'knock' from the gear box. I don't remember this before, but maybe I'm just paranoid. 

Should this be quiet or is a noise on reversal ok?

pete

--
Roland Christen
Astro-Physics


Peter Santangeli
 

I've been trying to isolate some issues guiding my C11 on AP900 that look like might be backlash (strangely... in RA).

I just re-seated my RA worm (I did this 5 or so years ago). 

I just noticed that when I reverse directions at maximum slewing speed, there is a significant sounding 'knock' from the gear box. I don't remember this before, but maybe I'm just paranoid. 

Should this be quiet or is a noise on reversal ok?

pete