Topics

New iexos 100 Dec Slop #iEXOS-100 #VIDEO


Don <donsinger@...>
 

I just received a brand new iexos 100 mount after several months on order. After assembling it and having both the RA and DEC clutches engaged, I noticed that the Dec axis has a lot of slop. When I gently press against the counterweight bar, there is approximately 1/8" of very loose movement in both directions (total of 1/4" movement).

The only other mount I have had that had such a problem was an iOptron CEM-25p and I could never get it to guide acceptably, even after several trips back to iOptron. I purchased the iexos-100 for astrophotography with light gear (WO ZS-61).

I assume that the play in my new iexos-100 is not a 'feature' - is there any way to fix it or does the mount have to go back to the dealer for an exchange. I would rather fix it myself than send it back and have to wait another few months for a new one.

Input appreciated!

Thanks,
Don/KF7DS

 


Jerry Hubbell - Explore Scientific VP Engineering
 

HI Don,

Thank you very much for you purchase and you patience in receiving it.  I am sorry you have this adjustment issue.  Here is a video that our Director of Quality Control made to show customers how to adjust the gears on the iEXOS 100. I hope this will help you to adjust your mount. If you have any other questions or comments please contact Customer Support at service@... or call +1 (866) 252-3811.

https://youtu.be/mLXE_BMKVAw

Thanks again!
--
Jerry Hubbell
Vice President of Engineering

Explore Scientific, LLC.
jrh at explorescientific.com

www.explorescientificusa.com
1010 S. 48th Street
Springdale, AR 72762
1-866-252-3811

Author: Scientific Astrophotography: How Amateurs Can Generate and Use Professional Imaging Data
             Remote Observatories for Amateur Astronomers: Using High-Powered Telescopes From Home


Mark Slade Remote Observatory (MSRO) IAU MPC W54 Equipment
Wilderness, VA
Mounts
: ES PMC-Eight G11 + Telescope Drive Master (TDM)
Scopes: ES 165 FPL-53 ED APO CF, ES 102 FCD100 ED APO CF
Cameras:  QHY174M-GPS + FW, QHY163C
Misc: 3-inch 0.7x Focal Reducer Field Flattener, Filters: Luminance,
Red, V-band Photometric, Diffuser, 200 lpmm Spectral Grating

Software: MaxIm DL 6, Cartes du Ciel, Astrometrica, AstroImageJ, AutoStakkert!


Don <donsinger@...>
 

Thanks a lot Wes. It's great to know ES has trust in its customers to assist them to correct known issues. For me, that is a first for mount vendors.

Kudos to ES and much appreciated 

Off to the garage to work on the mount and finish the setup.  I am sure I will have other questions 

Best
Don


Don <donsinger@...>
 
Edited

Hi Jerry:

Hope you see this post.

No joy. The video makes is look easy, and it should be. I loosened the 3mm and 5/64" screws to make sure the worm was seated firmly against the main RA gear, before I tackled the real apparent problem of the worm itself moving back and forth (i.e. left and right), where the real slop was.

Got the worm nicely seated against the main gear and turned the pulley gearing and everything was nice and smooth and not binding.

So, next step was to tighten the worm using a coin as in the video. No go...that is in there so tight that it cannot be loosened or tightened. I tried using a pair of pliers holding the coin (a dime) and tried to loosen or tighten, just to break it free...the coin bent. So, tried a penny, same thing.

At this point I am a loss. I put everything together and I still have the same backlash/slop in RA totaling about 1/4" total - 1/8" in either direction, which is not acceptable.

The video made it look so simple and, honestly, it should have been, but turning the screw to get the worm from shifting left and right (i.e. the RA slop) seems frozen in place. Is there a tool that may work better than a coin?

Please advise.

Thanks,
Don Singer


Tyler Bowman - Explore Scientific Customer Service
 

Don,

Can you send me a email with your Information and i would like to take a look at the mount if you don't mind.

My email is Tyler@...


Don <donsinger@...>
 
Edited

Hi Tyler:

Just sent you an email.

Got thge response "Your message wasn't delivered because the recipient's mailbox is undergoing maintenance and can't accept messages now. Please try resending the message later"

My email is donsinger@...


Don


Doug Walker
 

I had the same issue. Read the video comments.

---- From: Don <donsinger@...> -- Sent: 11/16/20 - 17:17 ----

Hi Jerry:

Hope you see this post.

No joy. The video makes is look easy, and it should be. I loosened the 3mm and 5/64" screws to make sure the worm was seated firmly against the main RA gear, before I tackled the real apparent problem of the worm itself moving back and forth (i.e. left and right), where the real slop was.

Got the worm nicely seated against the main gear and turned the pulley gearing and everything was nice and smooth and not binding.

So, next step was to tighten the worm using a coin as in the video. No go...that is in there so tight that it cannot be loosened or tightened. I tried using a pair of pliers holding the coin (a dime) and tried to loosen or tighten, just to break it free...the coin bent. So, tried a penny, same thing.

At this point I am a loss. I put everything together and I still have the same backlash/slop in RA totaling about 1/4" total - 1/8" in either direction, which is not acceptable.

The video made it look so simple and, honestly, it should have been, but turning the screw to get the worm from shifting left and right (i.e. the RA slop) seems frozen in place.

Please advise.

Thanks,
Don Singer




--
Explore Scientific iEXOS-100
Canon T1i (no mod)
Canon 18-55mm zoom lens
Canon 75-300mm zoom lens
Astromania 60mm guidescope
ZWO ASI 120MC-S
Lenovo m93 / Win10Pro
NINA, DSS, SiriL, GIMP, Phd2


Don <donsinger@...>
 

Hi Doug:

Will do.

Don


Don <donsinger@...>
 

Hi Jerry and Tyler:

I took Doug's suggestion and looked at the comments at the end of the YT video regarding backlash adjustment

I spent around 2 hours trying to find the sweet spot and I cannot. Either backlash is too much or when I just adjust to remove it, I get a grinding noise during around 1/3rd of the revolution of the pulley.

As I note in my video, this is one fussy adjustment and I have worked a lot on my AVX and CGEM extensively with no issues.

Any help is appreciated...btw, that 5/64" screw is incredibly difficult to get at and just gave up on that.

My YT video can be found here https://youtu.be/mIOX6eEY9bY

Best
Don


Doug Walker
 

Yeah, I have that same issue I think. There is one spot that grinds. It'll work fine then it starts grinding again. I think I figured out that there must be some asymmetry in the large gear. Either the center bore is slightly off center or the circumference is not a circle. If it grinds I just run it with the clutch disengaged until the bind-y part is on the top side of the gear so it doesn't hit it during use. Now I'm not sure about this, at least not sure enough to say I'm sure. I just ran into it the last time I adjusted for backlash.

Doug

On 11/16/2020 11:25 PM, Don wrote:
Hi Jerry and Tyler:
I took Doug's suggestion and looked at the comments at the end of the YT video regarding backlash adjustment
I spent around 2 hours trying to find the sweet spot and I cannot. Either backlash is too much or when I just adjust to remove it, I get a grinding noise during around 1/3rd of the revolution of the pulley.
As I note in my video, this is one fussy adjustment and I have worked a lot on my AVX and CGEM extensively with no issues.
Any help is appreciated...btw, that 5/64" screw is incredibly difficult to get at and just gave up on that.
My YT video can be found here https://youtu.be/mIOX6eEY9bY <https://youtu.be/mIOX6eEY9bY>
Best
Don
--
Explore Scientific iEXOS-100
Canon T1i (no mod)
Canon 18-55mm zoom lens
Canon 75-300mm zoom lens
Astromania 60mm guidescope
ZWO ASI 120MC-S
Lenovo m93 / Win10Pro
NINA, DSS, SiriL, GIMP, Phd2


Hughes Thompson
 

Don,

I have had a similar problem trying to get my iEXOS-100 RA axis adjusted.  When I got my mount a couple of months ago it had a some backlash in RA so I adjusted it following the YouTube video.  After that it started locking up occasionally when slewing and I tried adjusting several times.  I have always noticed the crunching noise when turning the gear by hand.  I checked the DEC axis which has always been ok and I noticed the same noise.  I'm wondering if it is just coming from the belt as you push on it.  If not I have the same problem in both axes.  After many hours of adjustment and testing I have concluded that I will have to live with a little backlash in RA to prevent binding of the gears.  There is also a little backlash in DEC which I have never adjusted but it only locked up once when testing.  I have contacted ES who suggested sending the mount in and that will be an option if I have further issues.

I agree that it is a fussy mount to adjust and I would prefer no lash at all.   I have a heavy load on my mount, 12 pounds with OTA, guide scope and cameras and 11 pounds of counter-weights.  Tracking and guiding seem to be OK and I have taken many hours of exposures with good results.

Hughes


 

Guys,
 
All I've seen of the iExos-100 is Alex's video and a few pix, but as far as I can tell, the gear adjustment concept will be the same as the EXOS2.  Yes, ring gear vs wheel gear and all that, but you're still talking about trying to achieve a perfect mesh between two rotating components, neither of which will be perfectly round.  So you're looking for an optimum solution, not a perfect one.
 
Try reading this, just for concepts, and see if it helps.
- Bob


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


Wes Mcdonald
 

Regarding ra backlash

Ra is always driven in one direction.  Guiding does not reverse the ra it merely slows it down or speeds it up. The point is a bit of backlash in ra is not a problem in fact.  

Dec backlash is a different problem that might matter for guiding.  This is “handled” by having a camera heavy deck balance.  It helps.  

Wes

--
Wes, Southport NC
EXos2-GT PMC-8, iExos 100
ES ED 127, 10" LX200GPS+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
Nina, Bootcamped Mac Mini control computer, RDP to iMAC
110 amp hour lead acid deep discharge battery for field power
Electrical Engineer, Retired


Don <donsinger@...>
 
Edited

Thanks for the feedback guys.

I just guess this is a 'feature'.....

I have so much grinding noise that I am going to adjust as much of that out and see where backlash falls. Honestly, the screw at the end of the worm gear should not be shipped so tight that one cannot adjust it - otherwise, the user is having to adjust things in a way that gets the alignment askew, and I think that results in the grinding noise. 

The grinding noise is like a pain one experiences - it is telling you something that something is not right. Hughes, good to hear that this can be guided out because I only do imaging and was worried that this will not result in round stars.

UPDATE: Hughes, you nailed it!!! with your statement ' I'm wondering if it is just coming from the belt as you push on it." I turned the worm by gently rotating the belt gear on the belt side of the worm without pressing on it and, voila, 90% of the grinding went away...just a small spot at one point of the full rotation has that grind and I do not feel it will present a problem in operating the mount.

And, no more RA backlash.

Want to thank everyone on the group that made suggestions...you are all wonderfully helpful

Cordially,

Don


Hughes Thompson
 

Don,

Glad it worked out.  Interested to know if you have any binding issues with all the backlash taken out.  Also, I had the same issue not being able to turn the screw on the worm gear bearing block.  I had to adjust the same way, by loosening the screw holding the block in place.  Hope this is not causing a problem.

Hughes