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CEM25P problem with DEC movement

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37 replies to this topic

#26 cytan299

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Posted 11 February 2019 - 03:22 PM

Yes, basically they are asking to me dismantle and see if there are any obvious issues with the hardware.

Unfortunately, you *have* to open it up. I had a completely loose drive gear:

 

https://www.cloudyni...loose-dec-gear/

 

Also after tightening it up, the DEC controls got better, but I think the belt is too tight and choking the worm. I still get bad DEC movement when trying to move it under low speed. I haven't had a chance to open it up again to tune though.

 

I know a lot of people swear that iOptron products work great, I, OTOH, can only swear at iOptron products.

 

cytan



#27 tkottary

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Posted 11 February 2019 - 07:48 PM

Thanks for the tip, when I opened the Dec gear last week I did not see any lose parts, I was able to move the drive gear slightly with hand but did not notice my DEC saddle move.

I will try that thing again. I plan to fully open it this week when I get time. 

 

Agreed I am not impressed with iOptron  product now, only bough this because of it being lightweight.



#28 gotak

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Posted 11 February 2019 - 08:18 PM

It's shipped a long way and if you ordered online it shipped the last few miles and maybe thrown in the truck and then your porch.

So it's not too surprising if something come loose.

There are exactly zero mounts shipped long distance that doesn't have such risks.

In the end their design is very simple so shouldn't be too hard to fix if it's a simple lose component.
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#29 StarMike8SE

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Posted 12 February 2019 - 09:58 AM

Wow, I guess I have to open mine up as well.  This is not what I wanted when I bought this.  I noticed the saddle has a little play in it, which concerns me.  While guiding I will get around 0.8" RMS error for several minutes, then get a big jump to 2.5".  It eventually settles but takes awhile then I will get another big jump.  sounds like some backlash or something loose



#30 santafe retiree

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Posted 12 February 2019 - 10:41 AM

Here are the "official" links for adjusting the belt tension and removing play in the Dec and RA axes:

 

http://www.ioptron.u...elt_tension.pdf

http://www.ioptron.c...Play_Fixing.pdf

 

I opened mine up for a "look see" and it is a very simple operation 

 

BTW mine regularly guides at 0.5 RMS and never above 0.8 -- total load is 18lbs (ES 102 FCD100 aluminum tube, Astromania 60mm guidescope, ASI224 as guider, Canon T6i as imager)

 

Cheers,

 

Tom


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#31 StarMike8SE

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Posted 12 February 2019 - 10:54 AM

Here are the "official" links for adjusting the belt tension and removing play in the Dec and RA axes:

 

http://www.ioptron.u...elt_tension.pdf

http://www.ioptron.c...Play_Fixing.pdf

 

I opened mine up for a "look see" and it is a very simple operation 

 

BTW mine regularly guides at 0.5 RMS and never above 0.8 -- total load is 18lbs (ES 102 FCD100 aluminum tube, Astromania 60mm guidescope, ASI224 as guider, Canon T6i as imager)

 

Cheers,

 

Tom

Thanks for sharing



#32 tkottary

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Posted 12 February 2019 - 01:49 PM

Update: Opened up the dec casing last night . Noticed that when the tension knob was fully tight, I could still move the worm house casing .  I had to slightly nudge it in.

 

This was the reason for play in dec saddle. Adjusted couple of  bolts  that was mentioned in the pdfs and play went away.

 

Moving the drive gear moved the dec saddle smoothly without any noticeable backlash. 


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#33 cytan299

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Posted 13 February 2019 - 06:54 AM

Wow, I guess I have to open mine up as well.  This is not what I wanted when I bought this.  I noticed the saddle has a little play in it, which concerns me.  While guiding I will get around 0.8" RMS error for several minutes, then get a big jump to 2.5".  It eventually settles but takes awhile then I will get another big jump.  sounds like some backlash or something loose

Or too tight. See this:

 

https://www.cloudyni...-zeq25-tune-up/

 

cytan


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#34 StarMike8SE

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Posted 15 February 2019 - 10:46 AM

Or too tight. See this:

 

https://www.cloudyni...-zeq25-tune-up/

 

cytan

Thanks



#35 StarMike8SE

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Posted Yesterday, 07:08 PM

Here are the "official" links for adjusting the belt tension and removing play in the Dec and RA axes:

 

http://www.ioptron.u...elt_tension.pdf

http://www.ioptron.c...Play_Fixing.pdf

 

I opened mine up for a "look see" and it is a very simple operation 

 

BTW mine regularly guides at 0.5 RMS and never above 0.8 -- total load is 18lbs (ES 102 FCD100 aluminum tube, Astromania 60mm guidescope, ASI224 as guider, Canon T6i as imager)

 

Cheers,

 

Tom

Looking at these PDFs, this looks a little daunting.  I am not the best handyman. You guys say it is easy, I just don’t want to damage my mount



#36 gotak

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Posted Today, 06:56 AM

Looking at these PDFs, this looks a little daunting. I am not the best handyman. You guys say it is easy, I just don’t want to damage my mount


Well it is going to carry some risk. However, if you take your time and do everything slowly and carefully it should work out ok.

The real risk is if you cam the worm over the wheel. If you avoid that the rest is a lot less risky.

#37 Stephen S.

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Posted Today, 10:25 AM

Looking at these PDFs, this looks a little daunting.  I am not the best handyman. You guys say it is easy, I just don’t want to damage my mount

Maybe get your local scope dealer to do it?

 

cheers,

 

Stephen



#38 StarMike8SE

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Posted Today, 10:30 AM

Maybe get your local scope dealer to do it?

 

cheers,

 

Stephen

no local scope dealer.  I will take ti slowly




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