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Problem with my EQM mount

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#1 sonofzen1

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Posted 17 October 2020 - 09:58 PM

My eqm mount is having trouble tracking. What I've noticed is that it has been making strange noises for the past few weeks or so when I've been out imaging. It sounds like light ticking like tapping a pen on the side of a table. I've also heard terrifying shreeks coming from the machine when ever it contorts at odd angles, almost like a plea for help. I brushed off the problem as something that would resolve itself, but I don't I can go on ignoring it any longer. Now when I take an exposure any longer than 30 seconds I see star trailing along the RA axis (see attachment). Something else I've also noticed is that the DEC axis isn't as responsive as the RA one. I actually have to hold down the arrow keys on my synscan controller for longer if I want to move along the declination axis as opposed to right ascension. Another thing I've noticed is that when taking everything off my rig and unlocking the radial attachment screws for the DEC axis, there is slight resistance if I freely move the axis in the positive direction.

 

Now I've seen to have isolated the problem, but I feel it's necessary to provide a little background:

  • I'm using the celestron 8SE as my main telescope. It's an 8inch schmidt cassegrain and weighs about 17 lbs I believe
  • My equatorial mount is the Sky Watcher EQM 35 pro with a maximum weight capacity of around 22 lbs
  • When stowing away the mount the mount I park it in the home position using the synscan controller (I don't use pc direct mode atm), and haul everything as it is from from driveway to the garage as is (about 5-10ft). I don't disassemble the mount, I don't even bother to rebalance it the next night of imaging. I know this is bad practice, but I'm lazy and figured the only consequence I would face was having dust build up on the lens of my scope. 

I suspect I'm overloading the mount over its maximum weight. Another problem I think could be contributing is a faulty connection between my DEC axis on the mount, perhaps the motors aren't getting enough power. I also suspect I may not be balancing everything right in the first place since there seems to be some resistance along the joint for the DEC axis. Maybe all I need to do is regrease the joints and the gears. I don't really know, but just in case I'll attach a picture of the DEC motors with out the protective covering on, so y'all can see if anything looks out of place, i.e. too much stress, etc.

Worse case scenario: I broke my mount and need to buy a new one, or I need to mail mine in to be serviced only to receive it back months after the fact with a note from the manufacturer saying nothing is wrong. 

 

Any ideas? Please help

 

Pictures:

https://drive.google...ew?usp=sharing 

https://drive.google...iew?usp=sharing



#2 Couder

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Posted 17 October 2020 - 10:34 PM

Difficult to diagnose from far away. My first choice would be to see if the gears are not meshing properly. If so, this could be due to loose screws, too much weight, or bumping the scope while moving, thus changing the gear mesh. Second choice would be send it in for service, which would be cheaper than a new mount. 



#3 sonofzen1

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Posted 18 October 2020 - 12:47 PM

I opened it up. Not sure if that voids my warranty, but I found that the gear mesh was improperly aligned. Some gears are slightly tilted off axis. What do I do from here?



#4 sonofzen1

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Posted 18 October 2020 - 12:50 PM

I also may have... dropped it while trying to service it...



#5 Couder

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Posted 18 October 2020 - 04:24 PM

Gears should mesh without slop, but be ever so loose as to prevent binding. Somewhere there is a way to adjust the mesh. It will probably involve loosening whatever keeps the adjustment screw from moving, tightening the mesh, then tightening the ones you loosened first.



#6 Stelios

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Posted 19 October 2020 - 03:22 AM

Moving to Mounts for more help.



#7 PKDfan

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Posted 19 October 2020 - 11:35 AM

For Gods sake Sonofzen1 stop carrying it whole outside! You will definitely WRECK it and then you WILL need a new one! These are relatively delicate pieces of tech. and dont like harshness or a heavy hand.

CS & GS
  • bobzeq25 and Ramauld like this

#8 bobzeq25

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Posted 03 November 2020 - 11:54 AM

For Gods sake Sonofzen1 stop carrying it whole outside! You will definitely WRECK it and then you WILL need a new one! These are relatively delicate pieces of tech. and dont like harshness or a heavy hand.

CS & GS

Agree.  It's far better to carry everything in small pieces, disassembled.

 

I've also read your planetary nebulae thread.   You seem to have inadequate understanding of just how sensitive and critical all these things are in traditional astrophotography.  Mounts are trying to do a very hard job, following a moving target to an error of less than 1/1000 of an inch.  A too big scope is compounding your problems, the EQM is only good for traditional AP with a quite small scope.

 

AP is nothing at all like visual astronomy.  You might want to check out the Electronically Assisted Astronomy forum, EAA is an intermediate technique where the mount is not as important, and larger scopes can be used more easily.


Edited by bobzeq25, 03 November 2020 - 11:54 AM.



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