Motor drive / tracking problems on an EQ2 mount

[pblackwell]

Hello everyone,

Im having an issue with my SkyWatcher EQ2 mount and motor drive.
The drive making a strange 'clunking' noise every 10 seconds or so, and this was accompanied by a big judder that caused the image to dance around.

Also most of the time it doesn't even move the RA even though the motor drive is turning the bigger gear/cog. The teeth seem ok on the gear/cog because they do turn but RA doesn't move at all. 

This is a repeatable problem when testing indoors and scope telescope correctly balanced.

What could this be and how can I resolve it?

Many thanks

Paul

 

[Guest]

while i dont own the ra motor i did read up on the issue here http://astrobeano.blogspot.co.uk/2012/01/multi-speed-motor-for-skywatcher-eq2.html

if you scroll down to the teething problem section it sounds like the problem you are having. hope it helps

[pblackwell]

Thanks for your reply Dakaar. But I've tried adjusting the T-bar (tightening and loosening) but it still jumps.

Apart from it jumping, nearly all the time the motor turns the large tooth cogged wheel but the RA still doesn't move.

To test I disengaged the motor and turned that large clogged wheel by hand. Sometimes RA will move and sometimes it doesn't. So I don't think it's a motor issue  if when I turn by hand the RA still doesn't move :/

[Alan64]

If you're up to it, and good at tinkering, disassemble the mount-head, both axes one at a time, and clean out the old factory grease and re-lube with a quality grease.  I use this for all of my astronomical equipment...

https://www.amazon.co.uk/d/Lubricants/Super-Lube-Synthetic-Grease-Syncolon-Multi-Purpose/B000XBH9HI

It's PTFE, or Teflon, based.  There are other greases that can be used as well, and instructions online to help in disassembling.

[pblackwell]

11 hours ago, Alan64 said:

If you're up to it, and good at tinkering, disassemble the mount-head, both axes one at a time, and clean out the old factory grease and re-lube with a quality grease.  I use this for all of my astronomical equipment...

https://www.amazon.co.uk/d/Lubricants/Super-Lube-Synthetic-Grease-Syncolon-Multi-Purpose/B000XBH9HI

It's PTFE, or Teflon, based.  There are other greases that can be used as well, and instructions online to help in disassembling.

Thanks Alan, this could well be the case. There's a lot of resistance when using the manual RA flexible control cable, when compared to using the Dec flexible control cable.

[dannybgoode]

What scope are you using-could you be overloading the mount so it can't move wick enough. The clunk sounds like a gear jumping and could be partly the issue and could also indicate overload. 

[BXRO]

Also worth checking that you are not driving the OTA against the DIN plug that connects the controller to the motor, there's not a lot of clearance between them at high elevations

[Alan64]

There could be pieces of metal shards lodged inside, and from the factory.  It wouldn't be the first time.

When cleaning out the old grease, I've found that charcoal-lighter fluid, the kind for grilling outdoors, works wonderfully in removing all traces of the old grease, with rags and an old toothbrush.  I did the same to my EQ-3.  It's much smoother now.

When re-greasing, only small amounts of the new grease are needed, particularly with the Super Lube.

 

[pblackwell]

I did some more testing and found that even if I disengage the motor drive and manually turn the big gear/cog by hand, sometimes RA moves and sometimes it doesn't.

I also found that when trying to use the RA flexible control cable, there was lots of resistance and it was hard to turn compared to the Dec flexible control cable which was light and smooth when turning.

Contacted the place it was purchased from and explained the issue to them and they're going to replace that part of the mount so happy days!

However, got the feeling it could be that the bearings are buggered and/or needs re-greasing.......guess Ill never know!

Thanks

Paul

[brantuk]

Great result Paul! Glad your gonna get sorted - and it saves you all the effort of stripping the mount down which you don't need right now.

[mikey2000]

A quick thought or two - I used to own a sky watcher EQ2...

On occasion, the Big Cog on the RA (the one the motor engaged with) would become loose. It would then appear to be turning with the motor but no longer be connected to the RA worm shaft, hence nothing happened.   It is held tight by a single Philips screw in the centre of the cog.  Tighten it up.    To further check for this cause, disengage the motor and try turning the big cog by hand.  The slow mo handle should rotate with the cog (they are merely opposite ends of the same long shaft).  If the cog is loose, the cog will just turn relatively freely with no apparent effect on the RA.

 

re: stiffness... did you disengage the motor (using that funny metal shape lever near the spring and big cog)?    With the motor still engaged, manual turning is difficult indeed, even if it is not running.

re: jumpiness - the motor cog is held against the big cog by a lightweight spring.  I occasionally had to give it an extra bit of encouragement to mesh properly and sit nicely - just a gentle push after using the funny shaped lever thing to engage.

[JohnSadlerAstro]

Hi,

When I owned an EQ2, my motor drive seemed to work ok, the main issue I had was the big hawser that seemed to be necessary to supply power from the handset to the motor ! I think really that the EQ2's drive is very basic, and as there 's no polar alignment scope,  I personally have spent 3 hours drift aligning, and still found it wanting. (Although I still used it in my 1st imaging attempts). I never got a stationary image. Thank goodness and an Uncle for supplying the money for an EQ5!

And just a thought----this thread was started in 2009, lol  

John

Edited February 2, 2017 by JohnSadlerAstro

[pblackwell]

17 hours ago, mikey2000 said:

A quick thought or two - I used to own a sky watcher EQ2...

On occasion, the Big Cog on the RA (the one the motor engaged with) would become loose. It would then appear to be turning with the motor but no longer be connected to the RA worm shaft, hence nothing happened.   It is held tight by a single Philips screw in the centre of the cog.  Tighten it up.    To further check for this cause, disengage the motor and try turning the big cog by hand.  The slow mo handle should rotate with the cog (they are merely opposite ends of the same long shaft).  If the cog is loose, the cog will just turn relatively freely with no apparent effect on the RA.

 

re: stiffness... did you disengage the motor (using that funny metal shape lever near the spring and big cog)?    With the motor still engaged, manual turning is difficult indeed, even if it is not running.

re: jumpiness - the motor cog is held against the big cog by a lightweight spring.  I occasionally had to give it an extra bit of encouragement to mesh properly and sit nicely - just a gentle push after using the funny shaped lever thing to engage.

Hi Mikey2000, I already did all the three things you mentioned but still had the issue. But anyhow, my mount is now in transit to the seller. First time I'm glad its bad weather because will take a few days to get the replacement

[starmattic]

Hey fellow stargazers! I am jumping back into this old thread because I am having trouble with my Orion 7827 EQ-2M Electronic Telescope Drive which is connected to an Orion 9024 AstroView 90mm Equatorial Refractor Telescope that came with an EQ-2 equatorial mount and accompanying lightweight tripod. I have read a few threads on issues related to using this motor drive, and know I am not the only one who has had issues with the motor's gear staying locked with the teeth on the RA cog on the telescope.  

The only heavy-ish thing I have attached to the scope is a Pentax XW 3.5mm eyepiece which adds about 14oz/400g-ish. I have made sure my right ascension is moving smoothly and easily (including with the fine adjustment knob) and that my scope is balanced, and have followed recommendations about how lose or tight the screw needs to be that holds the motor in place, how to seat the teeth of the gears, etc.

I have come to the conclusion that the little spring that comes with the drive that keeps it engaged is just too weak. When I apply gentle pressure to the underside of the motor housing, the gears stay locked and the motor drive moves the scope without issue, even at 4X speed. If I do not do this, the motor's gear ether periodically slips (clunk! shake!) or fails completely to turn the RA cog.

Obviously I don't want to keep a hand on the motor drive housing while using the scope. As an inelegant (and hopefully temporary) solution, I have wedged a round piece of foam from the Pentax eyepiece protective tube between the bottom of the motor housing and the top of the tripod. This seems to work fine.

I hope this helps someone. All I want is for this drive to work without fiddling with it. Seems like I've found a stopgap solution but I think I will contact Orion to see if they may be able to provide a sturdier spring. I don't know what else to do.

Thank you for hearing my tale.

Edited November 20, 2022 by starmattic

[Alan64]

On 20/11/2022 at 12:22, starmattic said:

Hey fellow stargazers! I am jumping back into this old thread because I am having trouble with my Orion 7827 EQ-2M Electronic Telescope Drive which is connected to an Orion 9024 AstroView 90mm Equatorial Refractor Telescope that came with an EQ-2 equatorial mount and accompanying lightweight tripod. I have read a few threads on issues related to using this motor drive, and know I am not the only one who has had issues with the motor's gear staying locked with the teeth on the RA cog on the telescope.  

The only heavy-ish thing I have attached to the scope is a Pentax XW 3.5mm eyepiece which adds about 14oz/400g-ish. I have made sure my right ascension is moving smoothly and easily (including with the fine adjustment knob) and that my scope is balanced, and have followed recommendations about how lose or tight the screw needs to be that holds the motor in place, how to seat the teeth of the gears, etc.

I have come to the conclusion that the little spring that comes with the drive that keeps it engaged is just too weak. When I apply gentle pressure to the underside of the motor housing, the gears stay locked and the motor drive moves the scope without issue, even at 4X speed. If I do not do this, the motor's gear ether periodically slips (clunk! shake!) or fails completely to turn the RA cog.

Obviously I don't want to keep a hand on the motor drive housing while using the scope. As an inelegant (and hopefully temporary) solution, I have wedged a round piece of foam from the Pentax eyepiece protective tube between the bottom of the motor housing and the top of the tripod. This seems to work fine.

I hope this helps someone. All I want is for this drive to work without fiddling with it. Seems like I've found a stopgap solution but I think I will contact Orion to see if they may be able to provide a sturdier spring. I don't know what else to do.

Thank you for hearing my tale.