how to adjust gears on EXOS 2 GT


rickbram
 

I saw the YouTube video on adjusting worm gears in the iexos100. wondering how to do that for the exos2-gt. Is there an equivalent video?I think I now have to work on that because I do hear some clicking in the mount when it slews at the higher speeds. Also, auto guiding fails when I try, with Ekos complaining about too much backlash. I suppose, the other problem might be that it's a little hard for me to perfectly balance the weight versus the camera/lens because even with the clutch fully disengaged, the axes are not really completely free to rotate. there is some mild friction. Thank you for any tips

--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


Eduardo Simone
 

Check the files tab, there’s a pdf on tuning the exos2

Ed
--
Meade LX 80 6" SCT and Meade DS 114mm Newtonian
Meade 2nd Digital Series Goto mount with 497 bandbox
ExploreScientific Exos II with PMC-8
ZWO ASI533MC-Pro
ZWO ASI120MC


 

Rick,

For gear adjustments, balancing tips, etc. try this:

https://espmc-eight.groups.io/g/MAIN/files/User%20Contributions/EXOS2PMC8_TuningNotes_v2.pdf



--
Mounts: ES PMC-8 EXOS2, Serial
Scopes: SW 130P-DS, SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2 290M
Software: ASCOM 6.3, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64


rickbram
 

Thanks for the pointer to that adjustment protocol. I haven't worked through all the steps yet, but just by doing a little bit, things are working really well now. I was able to reliably guide for at least 30 minutes, in spite of windy conditions and maybe slightly less than perfect focusing. Very happy with progress so far. This is a terrific little mount


--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


rickbram
 

Shoot, now I'm back with the same can't-guide-after all problem I thought was solved.
Even though it all worked great several nights ago, last night I spent hours in the sub freezing temps trying to get guiding to work again. Calibration just refused to be accomplished, either using internal guiding on Stellarmate or using PHD2. 
This is quite frustrating, isn't I\
One question for the group. I notice I do still have the loud clicking when the mount slews. It is about 120 clicks per minute, and is definitely coming from the DE motor. I'm guessing this is a sign I have to take apart that motor and adjust the gears? It seems daunting.


--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


 

Rick,

I had some trouble with PHD2 calibration, back in the day.   
I'm assuming that your basics are ok (guiding focal length, pixel size, darks, etc.), and it's something else...
Basically, my mount wasn't moving far enough during calibration, either.  
I changed PHD2->Brain->Guiding->Advanced->Calibration distance, px from the default of 25, to 50 and that sorted it out.

One of the fun things about this hobby, is that photographic magic can happen, but only when a lot of things go right. :-)

If you decide to adjust your DEC, you've got the instructions.  No worries, not hard.  Just read the doc a couple of times before you start, and then take it one step at a time.


On Fri, Nov 26, 2021, at 14:40, rickbram wrote:
Shoot, now I'm back with the same can't-guide-after all problem I thought was solved.
Even though it all worked great several nights ago, last night I spent hours in the sub freezing temps trying to get guiding to work again. Calibration just refused to be accomplished, either using internal guiding on Stellarmate or using PHD2. 
This is quite frustrating, isn't I\
One question for the group. I notice I do still have the loud clicking when the mount slews. It is about 120 clicks per minute, and is definitely coming from the DE motor. I'm guessing this is a sign I have to take apart that motor and adjust the gears? It seems daunting.


--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


--
Mounts: ES PMC-8 EXOS2, Serial
Scopes: SW 130P-DS, SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2 290M
Software: ASCOM 6.3, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64


Wes Mcdonald
 

Rick:

I believe what you are hearing is the belt scraping against the DEC motor plastic housing screw boss.  The spacing in there is quite close.  The remedy is two fold:
1.  Move both the large and small pulley inward on their respective shafts (worm and motor)
2.  Maybe file the boss a bit flat on the side where it comes closest to the belt.  The problematic boss is the one up by the large pulley.

This sounds daunting but it is not.

1.  Remove your rig from the mount
2.  remove the four small screws recessed into the black motor mount plastic shell
3.  Remove the four little screws the hold the top shell to the motor mount.
4.  Carefully work the shells, top and bottom off, not the bottom shell will remain connected to the motor wires and should be held up in place by some tape or something to keep strain off the wires.
5.  You will now have access to the set screws that hold the pulleys onto the shafts.  You can loosen them and slide the pulleys inward toward the motor and worm a bit, maybe.  
6.  If you have to loosen the belt, which is likely, you loosen the big bolt that holds the motor mount to allow you to slice the motor closer to the worm, loosening the belt tension.  

7.  If you remove the little sight window cover from the dec axis you can see the belt turning, and assess if it is running up against the moto housing.  

8.  If you want to, when the shells are off you can file the boss where the belt is most likely to hit.

Follow Bob' instructions found in his document (https://espmc-eight.groups.io/g/MAIN/files/User%20Contributions) to put things back together again especially regarding aligning and tensioning the pulleys/belts

That should get rid of the noise.  Probably help guiding.

Wes.


--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100, ESG11
ES ED 127+MoonLite Focuser, 10" LX200GPS+ MoonLite focuser+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified, ASI071 cooled OSC, ASI MM290 guide camera
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


Micheal
 

Rick

   I have the EXOS2 GT mount also. I had it out last night and it took a long time to calibrate, and looked good not sure why but balance seems to be the most import item in guiding. With my 6" RC +50mm guide scope & two camera + power cables I have approx 25 lbs on the mount. And was getting between .22 and .40 arc sec when guiding.

 Item  that may make a difference are Grease and balance. When I adjusted the worm gear I removed the old grease and re-grease the worm gears and Dec and Ra gears with the moly grease per instruction. This seem to be less stiff than what I removed and could make a big difference for the cold nights we have in here in MN. Then I had to re-adjust the dec and worm gears as I didn't tun the Dec or RA gears a full 360 deg and had similar problems that you are having.  When I do have  problems with guiding after the third try I go to unguided as I can get 30 - 60 sec unguided if I have a Good or Excellent polar alignment. Last night I only had Fair.

Not sure if you have had to do a meridian flip yet but I had a Big Problem with this. I was following Saturn and wasn't watching where Saturn in relation to the Meridian and after crossing the meridian + about 1.5 degrees the mount stopped and made a Huge racket as The Dec hit the Ra motor cover and stopped. I've sense always make sure I have the Dec motor cover on the west side of the mount for the home position.

Clear sky's

Micheal

IExos-100 and EXOS2GT both running PMC-Eight version 20A01.1
Svbony 503 80MM f7 w/ Orion 0.8 field flattener
Celestron 150mm C6n f7 w/motor focuser controlled w/ FCUSB Motor Controller
Svbony 50 mm guide scope on 80mm Scope
Svbony 60 mm guide Scope on 150 mm Scope
Cameras Canon T7, ZWO 224, ZWO 120mm, ZWO 120 MC 
DewBuster controller for 2 temp controlled dew strips, plus up to 4 additional dew strips, It also is Powering my Canon T7 camera, a 7 port USB Power hub, and fan for the 150mm Scope.
ASCOM 6.5 sp1 with Device Hub. Cartes Du Ciel for mount control, SharpCap for Polar alignment and planetary photos, Astro Photography Tool, platesolve2, PHD2 for guiding, and Stellarium for object framing only.

On 11/26/2021 1:40 PM, rickbam wrote:
Shoot, now I'm back with the same can't-guide-after all problem I thought was solved.
Even though it all worked great several nights ago, last night I spent hours in the sub freezing temps trying to get guiding to work again. Calibration just refused to be accomplished, either using internal guiding on Stellarmate or using PHD2. 
This is quite frustrating, isn't I\
One question for the group. I notice I do still have the loud clicking when the mount slews. It is about 120 clicks per minute, and is definitely coming from the DE motor. I'm guessing this is a sign I have to take apart that motor and adjust the gears? It seems daunting.


--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


Wes Mcdonald
 

Michael:

The PMC8 does not do a meridian while tracking -- it is content to track through meridian and crash.

If you do a goto post meridian it will do the right thing.  NINA for one, manages this, and stops imaging prior to commanding a meridian flip.  Works like a charm.

So if you are managing the imaging just stop imaging near meridian and wait for the target hour angle to pass zero.  Then command a goto and after the mount performs a meridian flip start your imaging again.  If you use NINA and maybe other site automation software, this is all managed for you automagically.

Wes.


--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100, ESG11
ES ED 127+MoonLite Focuser, 10" LX200GPS+ MoonLite focuser+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified, ASI071 cooled OSC, ASI MM290 guide camera
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


rickbram
 

Thank you Michael, that sounds like very good advice. I did go today and purchased some spray lubricant with teflon that says it is safe for plastic and metal and should hold up better when it gets below freezing. I'll try to replace the grease inside with this stuff.
Good point about just going for shorter shots when guiding isn't working, rather than banging head against the wall. I did get a very good polar alignment last night, at least as far as Ekos was telling me. Also, the default tracking from the mount seemed spot on.



--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


rickbram
 

Thank you Wes, I will give this a try. I appreciate the step by step. Will try to stop complaining, at least for a few more days. 
--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


Micheal
 

Wes

   This is basically  what I'm doing know with APT. But with the Dec on the west side. With My iEXOS 100 I didn't need to be a precise as the EXOS 2 GT and was a big surprise.

Micheal 

On 11/26/2021 4:23 PM, Wes Mcdonald wrote:
Michael:

The PMC8 does not do a meridian while tracking -- it is content to track through meridian and crash.

If you do a goto post meridian it will do the right thing.  NINA for one, manages this, and stops imaging prior to commanding a meridian flip.  Works like a charm.

So if you are managing the imaging just stop imaging near meridian and wait for the target hour angle to pass zero.  Then command a goto and after the mount performs a meridian flip start your imaging again.  If you use NINA and maybe other site automation software, this is all managed for you automagically.

Wes.


--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100, ESG11
ES ED 127+MoonLite Focuser, 10" LX200GPS+ MoonLite focuser+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified, ASI071 cooled OSC, ASI MM290 guide camera
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


Micheal
 

Rick

    I'm not sure I would use a spray lubricant seem you would need to apply it often to work. I just went on amazon and order this.

Liquid Moly 2003 Mos2 Long-Life Grease, 100 ml

Micheal

On 11/26/2021 4:34 PM, rickbram wrote:
Thank you Michael, that sounds like very good advice. I did go today and purchased some spray lubricant with teflon that says it is safe for plastic and metal and should hold up better when it gets below freezing. I'll try to replace the grease inside with this stuff.
Good point about just going for shorter shots when guiding isn't working, rather than banging head against the wall. I did get a very good polar alignment last night, at least as far as Ekos was telling me. Also, the default tracking from the mount seemed spot on.



--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


Wes Mcdonald
 

Rick:

Be sure to follow Bobs notes.  He details all of this and other things too.  Just do the parts I talked about.

Wes.

--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100, ESG11
ES ED 127+MoonLite Focuser, 10" LX200GPS+ MoonLite focuser+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified, ASI071 cooled OSC, ASI MM290 guide camera
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


Wes Mcdonald
 

Rick:

Yes, please use the moly.  I believe Bob suggests a type also, Michael's and Bob's might be the same.  The issue is that worm gears are hard on lubricant as they basically push it away.  The moly is better for staying on the worm and also has the cold weather performance you probably need.  

Wes.

--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100, ESG11
ES ED 127+MoonLite Focuser, 10" LX200GPS+ MoonLite focuser+wedge, Astro-Tech 8" Newt, ETX-90, 60mm no-name guide scope ~ 260mm FL
Polemaster, Orion ST-80 and SAG, ZWO 290MM, D5300 astro modified, ASI071 cooled OSC, ASI MM290 guide camera
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


rickbram
 

I will order some. Many thanks, again

--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini


 

Yes, that's the same grease. 
 
Basically an automotive grease intended for hard service (CV joints, bearings, etc.), and consequently also for wide temperature ranges.  The molybdenum disulfide (MOS2) additive acts much like graphite embedded in the grease, so two lubricants in one.  Messy stuff, soft and sticky, but it seems to cling pretty well to the worm.
 
 
--
Mounts: ES PMC-8 EXOS2, Serial
Scopes: SW 130P-DS, SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2 290M
Software: ASCOM 6.3, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64


Christopher Engell
 

Hello all, I just ordered this from eBay the "Liqui Moly Long-Life Grease Molybdenum C.V. Joint MoS2 100g tube (1) LM2003" cost $7.60 + tax and FREE shipping, I was not sure if I can post outside links?

But I really hope this is the BEST choice for the gears lubricant for our ES EXOS2-PMC-8?

Thank everyone!
Christopher


 

Christopher,

“Best” is in the eye of the beholder.  There are several other greases that people use and like for mounts.  This is just the one I ended up happy with. 


On Sat, Nov 27, 2021, at 12:09, Christopher Engell wrote:
Hello all, I just ordered this from eBay the "Liqui Moly Long-Life Grease Molybdenum C.V. Joint MoS2 100g tube (1) LM2003" cost $7.60 + tax and FREE shipping, I was not sure if I can post outside links?

But I really hope this is the BEST choice for the gears lubricant for our ES EXOS2-PMC-8?

Thank everyone!
Christopher


--
Mounts: ES PMC-8 EXOS2, Serial
Scopes: SW 130P-DS, SV 102EDT, ZWO 60/280 Guide
Cameras:  Nikon D5300, Altair GPCAM2 290M
Software: ASCOM 6.3, CdC, AstroTortilla, BYN Pro, Sharpcap, PHD2
Computer:  Thinkpad x230, Win7Pro/64


rickbram
 


Awaiting molyMN grease and had clear skies last night, so tried some more imaging with guiding.
Very interesting, my setup seemed to work fine if I targeted east of the meridian. I got in more than an hour of tracked, guided images. Then, it did a meridian flip, and guiding no longer would calibrate. So maybe I should work on the placement of the weight along the balance bar. 


--
Rick, Minnesota USA
EXOS2-GT, Stellarmate/Astroberry, Askar FMA230, ASI294MCPro, ASI120mini guidescope, ASI120mini