Help ! EQ1, EQ2, basic and deluxe RA motor choice

[Astro-Geek]

I've just acquired a used Konusmotor 130 telescope and mount for a specific purpose.

I know the OTA is regarded as rubbish, (with the extra lens element inside to enable a shorter OTA), but I was only interested in the EQ mount, so the OTA is going to be discarded.

I already have a very nice EQ5 goto for imaging with my 200PDS, but I wanted a really lightweight EQ mount and tripod for my Lunt LS35 and maybe my Skymax 127 for visual use only that I can grab and go (even with the counterbalance weight attached).

The Konusmotor came up for a good price and it appeared to have a hybrid version of the EQ2 mount with enclosed bevel gears and a vixen saddle.

I stripped it down completely and rinsed the Chinese Evo-Stick grease out of it and re-assembled it carefully with lithium and adjusted the RA and DEC play and I'm now extremely pleased with it.  It is very smooth on the flexi SloMos and reasonably steady with my lightweight scopes and very convenient to carry around my front and back gardens and quickly set down facing North with the Lat preset, giving me good visual tracking (and so much better than AltAz  ! 🤓).

Anyway, to come to the point of this post, it was lacking the original fitment RA motor drive, so I'd like to fit a replacement.

I've been scouring the Internet to see what choice there is and which is the correct fitment for my hybrid EQ2 (at least that's what I think it is).  I'm getting very confused however. EQ1 and EQ2 mounts appear to be available as "basic" and "deluxe", with either an integral 9v battery or with a remote handbox, 6v battery pack, and x2 and x4 speed controls.

The choice is further complicated by the EQ1/EQ2 variations.  One sort is connected directly to the slowmo shaft by a flexi coupling, and the other sort has a small gear that meshes with the large gear cog on the mount.  I found the attached picture on the Internet where the apparently original motor fitment on the Konusmotor 130 was the flexi shaft type, which I find strange, since it makes the large gear cog and cam redundant ?  I'd rather not get that type since it does not use the EQ2 clutch provision of the gear wheel, cam lever, and spring, which enable quick clutch release.

So, if I got the gear cog/spring type would it turn the Konusmotor's RA at the correct speed ?  (I'm thinking it surely should, since those gear wheels look like a standardised size on these small EQ mounts.

Lastly ! (sorry about the length of this), is the difference between the basic and deluxe EQ1/2 motors more than just the control box and battery holders ?  Is perhaps the deluxe motor more sophisticated and accurate ?

 

[Alan64]

Note the drive that comes with a new Konusmotor-130 kit...

That drive is the same as one of these...

https://www.firstlightoptics.com/sky-watcher-mount-accessories/ra-economy-motor-drive-for-eq1.html

https://www.firstlightoptics.com/sky-watcher-mount-accessories/ra-single-speed-motor-drive-for-eq-2.html

Both of those 9V-battery drives have a variable speed control, which may very well be an advantage in being able to compensate for any deviation between the RA-gear of the Konus mount and that of a Synta EQ-2.

The deluxe drive with the hand controller and the battery-pack does not have a variable speed control.  I'm not referring to the slew speeds, but to the rotation of the RA-gear.  Also, I can't say for certain if that deluxe drive would work with the Konus mount.

Before using any motor-drive, ensure that the worm-shaft and the RA-gear are butter-smooth in operation, with no slop or binding, and to keep from damaging the drive.

Incidentally, I have a Celestron 127EQ OTA, a "Bird Jones", and practically identical to that Konus OTA.  I just recently and successfully collimated my own.  Have a look at this afocal shot I took with the bundled 4mm Ramsden or whatever it is, and at 250x...

That was with the telescope on a shaky mount, and with my hand-holding a small point-and-shoot camera up to the eyepiece, so it is slightly blurred.  The live view was virtually tack-sharp.  I couldn't believe my eyes upon the event.  

Both my Celestron OTA and your Konus OTA are essentially 5" f/4 Newtonians with a "corrector", a doublet lens, installed at the bottom of the drawtube of the focusser.  An f/4 Newtonian is rather difficult to collimate, especially for a beginner, hence the bad reputation of this type of telescope.  I had to renovate the focusser of my own so that the drawtube racked in and out straight and true.  I also replaced the rubber grommets for the adjustment-screws of the primary-cell with metal springs.  I did many other things besides to the telescope, and it has certainly paid off.

Hence, I wouldn't discard that OTA, unless you simply do not want to be bothered with what's involved in getting it to perform at its best.  I found a gem hidden with my own, and it's a keeper.

Edited July 23, 2019 by Alan64

[bobro]

The basic/economy motors are just simple DC geared motors with a (tiny) control to vary the speed. When the basic motor starts it tends to run a little fast before settling down. Once the control is set to the correct speed it will track the sky reasonably well - when I started out with imaging my EQ2 Economy motor would allow 30 sec exposures with a 650/130 scope before drift became visible. For visual this is obviously not critical. Setting the speed is a little tricky with the tiny control. A disadvantage is the loss of the slow motion control. The range of speed setting is large.

The motor with a handset provides precise speed control - it most likely has a stepper motor internally. The correct motor for the mount gearing must be used as there is no adjustment. The motor clutch allows the slow motion control to be retained.

I still have my EQ2 (Meade type) and can help with a comparison if that helps.

Bob

[Astro-Geek]

Thanks for the very prompt and helpful replies. It's so handy being able to tap into other people's practical experiences with this sort of thing.

 

Alan -

Yes, those two basic motors do look the same as the Konusmotor original fitment.   Thanks for the two FLO links.  Strange thing though, they look absolutely identical (front and back), and yet they are each specifically aimed at the two types of mount, and one is £3 more than the other !

I hear what you're saying about the fully adjustable motor (also making it seem strange that there are two types), but I really would prefer to go for the other type that has the gear wheel and spring, so that I can use the clutch that's already fitted as part of the mount's original equipment.  I think it would be so much more convenient to use the clutch type, enabling the use of the RA slomo flexi cable, rather than having to loosen the clamp bolt and physically move the RA.

Yes, I do understand the need to get the axial movement of the RA as smooth as possible and my rebuild appears to have achieved that, with the RA easy to turn even by just gripping the rubber flexitube, rather than the knob.

Interesting what you say about the optical performance of these low cost "Bird Jones" OTAs.  I must admit, I did pop in a good quality 20mm eyepiece and tried it out terrestrially in the daytime. It did indeed seem quite sharp, and that was without any attempt to check the collimation.

 

Bob -

You've confirmed something that seemed a possibility during my Google searches, the deluxe handset motors are more sophisticated timing-wise, and therefore non-adjustable. I really would prefer to go with that solution to make use of the already fitted clutch lever mechanism. I think I'd get really frustrated with the slow motion RA being permanently locked to the motor mechanism.

Going back to Alan's FLO links to the basic EQ1 and EQ2 motors, I'm now wondering if the difference between them is the flexi-coupler shaft rotation, because maybe the EQ1 and EQ2 have different gearing.  If so, then the appropriate EQ1/EQ2 handset type motor should match my Konusmotor's mount, as surely it is merely a clone of one or the other, albeit with enclosed bevel gears ?

 

Edited July 23, 2019 by Astro-Geek

[Astro-Geek]

I've been checking FLO's other motors for EQ mounts and the delux Hand set types also come in the two flavours, EQ1 and EQ2:

https://www.firstlightoptics.com/sky-watcher-mount-accessories/sky-watcher-ra-motor-drive-for-eq1-with-handset.html

https://www.firstlightoptics.com/sky-watcher-mount-accessories/skywatcher-ra-motor-drive-for-eq2.html

Interestingly, only the EQ2 type fits via the gear cog and spring and utilises the clutch.  The EQ1 type is just the fixed bracket, with a flex-coupler straight onto the shaft, like the economy models.

So it would appear that the only type that I can get that will use the clutch is the EQ2 handset model.

I'm surprised it's such a minefield, considering how popular the EQ1/EQ2 mounts are.....

[Cosmic Geoff]

I used the "economy" style drive on a EQ-2 clone mount some years ago. It was awful.

[Astro-Geek]

3 hours ago, Cosmic Geoff said:

I used the "economy" style drive on a EQ-2 clone mount some years ago. It was awful.

All feedback gratefully received !!

[bobro]

6 hours ago, Astro-Geek said:

So it would appear that the only type that I can get that will use the clutch is the EQ2 handset model.

I'm not 100% certain, but I recall the EQ1 and EQ2 having different gearing. That's not really an issue with the adjustable simple motor, so the physical attachment is what is important there. For a precision motor both the gearing and physical attachment are important : assuming that EQ2 gearing is correct for your mount, it will need to work mechanically with your mount. 

Although EQ1/EQ2 mounts (especially SkyWatcher, Celestron and Meade) sell in numbers, yours looks to be an older mount design that may be different from what is sold today.

[Astro-Geek]

Yes, it certainly looks different to most EQ1 and EQ2 mounts, they all seem to have open bevel gears, whereas mine are enclosed, as though it was a halfway house design towards the EQ3m, (which appears to have preceded the much more common eq3-2.

I'm still struggling with the fact that it has the swivel post, large gear wheel and cam lever for the clutch mounted motor, and yet all of the original Konusmotor 130 photos show it with the simpler direct drive via the flexi-coupling locked directly onto the slomo worm gear shaft.

Maybe, (just thinking aloud here 🙄), the coupling was modified to the direct drive because the earlier gear cog design suffered from "jumping" when the RA axis was stiff, and it levered itself away against the spring ?

I have another cunning plan though, if the simple motorization kit's motor speed adjustment is the safer option for getting the speed right, then maybe I could swap the flexi-shaft coupling's grub screw for a knurled knob, to enable it to be released (like the clutch) for manual slowmo operation ?

I'm still confused as to why the EQ1 and EQ2 motor kits sold by FLO are so specifically designated, even though they look identical (inside and out), and are different prices.

I did just drop FLO an email about this, but although they answered very promptly, they were unable to throw any more light on the subject......

[bobro]

These 2 youtube videos may help:

https://www.youtube.com/watch?v=Ps8d4P7fWK0

https://www.youtube.com/watch?v=xlGF7PYLpYE

 

[Alan64]

Back in the early 1990s, I had an original EQ-2, made in Japan...

I ordered a motor-drive for it.  It had a table-lamp type cord that plugged into the mains; no means of using batteries.  It was great.  I observed Venus one morning with it, from about 5:30 whilst it was dark, and up until about 11:00 in broad daylight.  With an occasional tweak of the declination, Venus remained centered in the eyepiece for the entire span.  In the end, the planets appeared as a pale sphere, and seemingly sprinkled with fine sand or other; like a sugar cookie.

You do have to tinker with the 9V-battery version to get it just right.  If you have the option to return it, go for the deluxe version.

I have a modern, Meade EQ-2 now, a Chinese clone.  Its cogwheel is 49-50mm in diameter...

...and it can make use of that deluxe drive.  But I had gotten the Celestron 9V-battery drive beforehand, which comes with two brackets, one for an EQ-1, and the other for an EQ-2...

Although, I've yet to use it; pity, that, therefore I don't know what to expect.  It has been known to drive an EQ-3, and successfully, by the way.  Both of those links for those 9V-battery drives state, "Can be fitted to any telescope supplied with the EQ1 equatorial mount".  Both also sport the same image; no rhyme nor reason.  

This is the RA-gear of the Meade EQ-2.  I do not know if that of the Konus mount is the same.  I've not measured it, nor have I counted its teeth...

The Konus is definitely not an EQ1-class mount.  It favours an EQ-2 rather, given its cogwheel and cam, and perhaps nigh to an EQ-3 at that; in certain aspects.

I cannot say yea or nay for either drive, I'm afraid.  

Incidentally, the coupler of those 9V-battery drives has a thumbscrew.  Conceivably, that may disengage, then re-engage the connection.  Thinking out loud, I was wondering about altering the worm-shaft, and in sporting either a 32- or 64-sided end there, so that when you batten that thumbscrew down it would catch and grab onto the shaft.

Edited July 23, 2019 by Alan64

[Cosmic Geoff]

A key variable is the number of teeth on the RA wormwheel (inside the mount).  The number of teeth will determine whether a given motor kit will drive at the right rate.

In theory, a given motor kit will drive any mount that has the matching number of teeth on its wormwheel, if attached to the slow motion shaft.

[Astro-Geek]

12 hours ago, bobro said:

These 2 youtube videos may help:

https://www.youtube.com/watch?v=Ps8d4P7fWK0

https://www.youtube.com/watch?v=xlGF7PYLpYE

 

Thanks for the links to those two videos Bob.

They've certainly provided even more food for thought.

The EQ2 motor vid shows it being fitted on the opposite side to the exposed gear wheel, necessitating the complete removal of the slowmo flexi handwheel control.

It also shows that the motor box is then "upside down", which make one think that it is indeed identical to the EQ1 motor, which fits on the other side and is the right way up and they haven't bothered to make a different box and graphics for it.  It would also mean that the shaft is being turned the opposite way (from the other end).  The North/South switching could take care of that I suppose.

To further confuse matters, the photos of the original Konusmotor 130 motor is fitted on the same side as the gear wheel, so it is the right way up. 

[Astro-Geek]

Thanks for the second reply Alan, and the photos.

Yes, I hadn't realised that the coupler on the simple drives already had a thumbscrew, and as the shaft is "D" shaped, it should be a firm fit without needing excessive tightening.

If I mount it on the same side of the mount as the exposed gearwheel (as in the original Konusmotor photos), then it'll be the right way up and I'll still have the slowmo flex drive on the other side, and the thumbscrew gives me a simple clutch option.

So that sounds the best way forward.

The only mystery now, is why are there two different simple motors from FLO (EQ1 and EQ2) that appear to be identical (and as in the two videos linked by Bob), and why are they priced slightly differently ? The geared motor looks the same size and the coupling and bracket are the same, and they are both speed adjustable.... 🤔

 

[Astro-Geek]

20 minutes ago, Cosmic Geoff said:

A key variable is the number of teeth on the RA wormwheel (inside the mount).  The number of teeth will determine whether a given motor kit will drive at the right rate.

In theory, a given motor kit will drive any mount that has the matching number of teeth on its wormwheel, if attached to the slow motion shaft.

Yes, maybe the EQ1 and EQ2 wormwheel bevels are slightly different diameters with a different number of teeth.  I searched high and low on the Internet, but could find no specific details on the gearing ratios, unlike all the info available for the EQ5 and 6 when they're EQ Modded....

[Guest]

I've watched this thread with interest as the old Meade 114-EQ1B I'm using has a similar type mount , with a similar type RA motor drive option as the original Konusmotor 130.

Edited November 8, 2019 by Guest