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Having trouble tracking with Super Polaris

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#1 GeoUniverse

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Posted 28 December 2012 - 12:29 PM

Hello everyone this is my first message, I believe after signing on. I purchased a used super polaris mount with DD-1 controller and motors as well as a battery pack, and was hoping to track decently. While I am able to slew with the 32x function on the controller the mount does not seem to track at all (I don't care about accuracy for the moment) simply the R/A drive will not move for hours on end, even if the motor seems to be running. I purchased a 12v universal power supply 2500 mA at a store nearby in case it was the batteries (which do indeed affect even slewing if they are low). However no success in tracking. Maybe I need 3000mA or something is wrong with the RA motor or DD-1 controller?
Sorry for being so long but I wanted to explain my case.
Thank you!

#2 panhard

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Posted 28 December 2012 - 12:40 PM

Welcome to our site. :band: :band: :band: :grouphug: :grouphug:
I found this on your mount I hope it helps you. Just click on the link. link
I could move this to the mounts forum, where you might get better quality replies.

#3 GeneT

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Posted 28 December 2012 - 12:43 PM

First poster--welcome! You have come to the right place for some help.

#4 GeoUniverse

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Posted 28 December 2012 - 12:51 PM

Feel free to move this to the mounts forum. I had seen this link, however did not know if would have tracking. I don't really understand the term backlash, but was told by the previous own that this mount didn't have any and took his word for it.

#5 CJK

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Posted 28 December 2012 - 12:54 PM

Backlash is just the "slack" in the gear train -- basically, the fact that the gears have to turn a small amount before whatever they're driving (in this case, your mount) starts to move. All gear systems have SOME backlash, but the best systems have almost no measurable backlash.

-- Chris

#6 GeoUniverse

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Posted 28 December 2012 - 12:55 PM

Panhard... I will try and work on those suggestions in the link this afternoon. Another problem I note, is that when I press in 32x slew mode a button to move the RA in one direction and then press the opposite button, to move in the other direction. I must often press the opposite button two or three times to get the direction to change. Finally it does. Is the the DD-1's age or some slipping that I can fix.

#7 GeoUniverse

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Posted 28 December 2012 - 12:56 PM

Thank you for the clarification. Will excessive backlash then cause non-existant tracking?

#8 Jon Isaacs

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Posted 28 December 2012 - 01:00 PM

Hello and welcome to Cloudy Nights. :waytogo:

As far as tracking goes, if it slews, it should track. The batteries should be fine. Can you see the shaft between the drive and the mount? Mark it and see if it moves at all. Often if a drive won't track, a lock or clutch is loose and slipping. It could even be a set screw that is loose.

I would try to determine if the drive output shaft is turning and then either look at the mount or the drive accordingly.

Jon

#9 drewp

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Posted 28 December 2012 - 01:06 PM

the shaft connected to the worm should be seen as turning when its running. i agree with Jon. probubly just a loose coupling or your trying to slew and track without locking down the clutch.

#10 GeoUniverse

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Posted 28 December 2012 - 01:07 PM

Thanks Jon. I will keep a careful watch on that shaft. It moves wonderfully when slewing, but not at all it seems in mere tracking mode. But I have taken note now and will watch it more carefully. This afternoon, I take out my wrenches and allen keys for a closer look.

#11 GeoUniverse

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Posted 28 December 2012 - 05:24 PM

After following the instructions on the recommended website and working on limiting the backlash, the mount seems to be tracking now inside the house and giving much better results than before.
I am looking to track the sun, I suppose sidereal rate would be the best for that besides the fact that the DD-1 does not give much of a choice. The setting is either 1.5, 2x or 32x, and that seems to be for slewing. Does anyone know any more about the DD-1 capacities and how it can be adapted to the sun, moon and planets... or if there are other options out there for the super polaris mount? Does anyone know if the D3M controller is much better.

#12 GeoUniverse

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Posted 28 December 2012 - 05:25 PM

And thank you everyone for all the help today!

#13 Geo.

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Posted 29 December 2012 - 02:04 PM

Doesn't the DD-1 operate on 6vDC?? If so, I'd loose the 12v adapter fast. The Nippon stepper isn't the most efficient drive in the world but 1 amp should be plenty.

#14 orlyandico

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Posted 29 December 2012 - 02:10 PM

the DD-1 is 12V. center NEGATIVE.

or rather.. 7.5 - 12V, the battery pack it comes with is 9V.

The most common source of this problem is slipping of the spur gear that's on the RA worm.

on my Vixen, I noticed that the RA shaft was 6mm... but the bore in the spur gear was 1/4" (6.35mm) - I had to torque down the grub screw in the spur gear really tight (and add a shim) so it wouldn't slip.

this shows up at tracking rate, but at 32X you can't see it because the gear turns fast enough to take up the slip/slack almost immediately.

#15 panhard

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Posted 30 December 2012 - 09:30 AM

You have to have a solar filter to look at the sun.






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