Scopetech Zero Mount Slow Motion Problem

[tompato]

Hi all, my Scopetech Zero Mount came today and it looks lovely. I've just put it on a tripod to test it and the clutches and movement seems to be fine. I noticed the slow motion controls on the altitude were barely moveable and I couldn't test the slow motion on that axis.

So I noticed the Flo website says to try loosening the tiny adjustment screws so I loosened those slightly and hey presto, I can turn the slow motion knobs now.

However, it will adjust one way but not the other. I've checked the telescope is as balanced as I can do I don't think it's that. I can turn the slow motion knob both ways, it's just to go towards the zenith it just doesn't move, whereas turning to lower towards the horizon is fine. On the azimuth it will turn to left easily but not the right very well (this axis does turn but not very consistently).

I'm leaning towards having a faulty mount but I thought these things were tested so maybe I am just doing something wrong. All the instructions are in Japanese with no translations so I might have missed something. I can take a video if that helps.

Edited May 25, 2021 by tompato
Clarity

[tompato]

Okay it seems I can sometimes get it to work in Alt by making ever so slight adjustments to the balance but then it doesn't work in Az, presumably because isn't balanced across the other axis as it's a Newtonian so the focusser and eyepiece are on one side.

To be honest if the functionality of the mount controls are this fine tuned to get it to work I might just have to return it. Maybe it's not suited to a Newtonian?

Also I can't go very far before hitting the clutch on the bottom of the tube (6 inch Newtonian).

Edited May 25, 2021 by tompato

[jock1958]

I’ve got my Tak FS60Q (a lot smaller than your 6” Newt) mounted on a Scopetech which still requires careful balancing. Before swapping eyepieces I tend to tighten up the Alt tension knob or the scope drops and contacts the Azimuth part of the mount. 
I messaged FLO about the tight Slo Mo controls and was advised to slacken off and retighten the brass coloured locknuts which helped a lot, also try Google translate with your phone on the instruction manual...it does work although it’s a bit clunky! 
I know @Stu has mounted bigger OTA’s on his Scopetech so he might be able to offer further advice. 

 

[tompato]

Thanks for the reply @jock1958. It does seem with some very fine adjustments it does kinda work with my telescope but it's very temperamental.

I've tried to adjust the bits in the maintenance guide to loosen up the Az slow motion and that does seem to have worked to some degree.

Please excuse my ignorance but the slow motion controls are supposed to work with the clutches loosened and tightened?

[jock1958]

Yeh you have to tighten the clutch knobs for the slo mo’s to work and adjust tension to suit your needs. 
It would help if Scopetech brings out an English version of the manual, also there is a Japanese video out as well, can’t remember where I saw it though 🤔

Edited May 25, 2021 by jock1958

[Stu]

10 minutes ago, tompato said:

Please excuse my ignorance but the slow motion controls are supposed to work with the clutches loosened and tightened?

Just to get this bit straight first, you keep the clutches tightened all the time, and can either pan the scope by pushing it or use the slow motion controls.

Which scope for you have? I could see that a 6” might be quite limited in terms of movement due to clashing with the az tension knob. I could try my Heritage 150p on mine to see if there is an arm position that works best. I’ve mainly used 4” scopes on mine which work fine, even a longer f8.8 Vixen.

I’ve been able to adjust the lock nuts so that the tension and motion are to my satisfaction so I think that, so long as the mount is not faulty, you should be able to do the same.

[tompato]

Yeah to clarify I don't mean I've loosened the clutches all the way, just slightly. I'll do s video of me trying to move them on both axis with nothing mounted. The Az moves fine, but the Alt doesn't seem to move the plate at all.

And I'm aware they're hard to turn without slow motion controls connected, but if the knob is turning I imagine the axis should move, unless the worm gear thing isn't meshed but I don't see why it wouldn't be.

[JeremyS]

12 minutes ago, jock1958 said:

Yeh you have to tighten the clutch knobs for the slo mo’s to work and adjust tension to suit your needs. 
It would help if Scopetech brings out an English version of the manual, also there is a Japanese video out as well, can’t remember where I saw it though 🤔

Each page of the instruction manual has a QR code which if you scan links to a video 

[jock1958]

Just watched your video you need to tighten the clutch knobs and some Slo Mo cables would help instead of trying to use your fingers 

[Stu]

8 minutes ago, tompato said:

Yeah to clarify I don't mean I've loosened the clutches all the way, just slightly. I'll do s video of me trying to move them on both axis with nothing mounted. The Az moves fine, but the Alt doesn't seem to move the plate at all.

And I'm aware they're hard to turn without slow motion controls connected, but if the knob is turning I imagine the axis should move, unless the worm gear thing isn't meshed but I don't see why it wouldn't be.

It looks like you have the tension clutches much too loose to engage the worm gear. I couldn’t turn the brass pin on mine with the clutch tightened enough the engage the worm. Try some slow motion controls on it with the clutches tightened.

[jock1958]

5 minutes ago, JeremyS said:

Each page of the instruction manual has a QR code which if you scan links to a video 

Your right Jeremy I totally forgot....dughhh!

[tompato]

5 minutes ago, jock1958 said:

Just watched your video you need to tighten the clutch knobs and some Slo Mo cables would help instead of trying to use your fingers 

Yeah, my fingers are destroyed. I will get something but no cables were in stock. I've ordered some 6mm potentiometer knobs which are coming tomorrow which should make it slightly easier.

I've made the adjustments of the small screws and the larger ones on the Alt and that seems solid and just about moveable when fully tightened and I've tightened up the Az as well to match the same sort of tightness. Both seem to move the axis correctly now. 

I'll give it a go with the telescope again.

Edited May 25, 2021 by tompato

[tompato]

Seems much better, I thought I'd made an expensive mistake when putting the telescope on it or when adjusting the tightness screws on the slow motion bit but it seems good now. 

Much thanks everyone 🙌

[jock1958]

4 minutes ago, tompato said:

Yeah, my fingers are destroyed. I will get something but no cables were in stock. I've ordered some 6mm potentiometer knobs which are coming tomorrow which should make it slightly easier.

I've made the adjustments of the small screws and the larger ones on the Alt and that seems solid and just about moveable when fully tightened and I've tightened up the Az as well to match the same sort of tightness. Both seem to move the axis correctly now. 

I'll give it a go with the telescope again.

Nightmare I can understand now why you’ve had these problems. You definitely need Slo mo cables or ADM do knobs, if all the usual places are out of stock try Astroboot. Once you have these your problems should disappear 

[jock1958]

Hi @tompato you inspired me to get my Scopetech & Tak FS-60 out last night, it’s ages since it’s seen any action mainly due to the awful weather we’ve had down here.
As an experiment I tried turning the Alt & Az worm gears with my fingers and it is very, very difficult and really sore on fingers, slo mo cables are a definite must. 

I have the clutch knobs moderately tight on mine but one thing I’ve noticed is the Az knob seems to loosen off after a few operations which I’m not sure about or why it does this?

Anyway let us know how you get on when you receive those control knobs and good luck! 

 

[tompato]

Thanks @jock1958

The knobs actually fit very well, they have a grub screw in the side so you can tighten them on. I think I could have gone for 30mm ones instead of 20mm ones but they at least allow me to turn the slow motion controls. I've set some email alerts when the long cable slow motion controls become available.

The Az knob is a joy to turn, it's smooth and tight but not too much. The Alt knob is a bit tougher to turn and it does almost feel like it slips occasionally, which is probably a sign I've not got it tight enough but any tighter adjustment of the tension screws and I can't turn the knob without significant hardship on my poor fingers.

I have tried loosening the case screws and following the instructions from Flo (I must admit I didn't quite understand the instruction where it tells me to hold the case against the body and tighten the case screws back on as they only seem to screw back in at one point only) on adjustment but whatever I do it just always seems to go back to being the same - which is too tight but loosening the tension screws puts it borderline on meshing properly or it has movement in the knob before it starts to engage.

I'm not really sure if there's much else I can do, I think I might have to accept the Alt is much tighter than the Alt, which is a shame because the slow motion control on the Az is so buttery smooth, and the tightness of the Alt just makes it quite jerky to use.

The video shows where I've loosened the tension screws so it turns and just about meshes, but it's borderline as it feels like it slips occasionally.

Edited May 26, 2021 by tompato

[jock1958]

The only things that I’ve adjusted (slackened off & re-tightened) are the brass locknuts on the ends of Alt & Az worm drive housings using two 13mm open ended spanner’s and clutch tension knobs on both axis, as recommended by FLO. 

Must admit I found those instructions above a bit confusing as well 🤔

I assume you’ve only tried FLO for the slo mo cables? there’s a few other vendors worth a try, Rother Valley Optics, Widescreen Centre & 365 Astronomy. I believe Astroboot is closed just now. 

Also might be worth a read of the thread @Stu started last year titled Scopetech Zero Mount. 

If u you like I’ll post some pics tommorow of my setup and where I adjusted mine. 

[Stu]

2 minutes ago, jock1958 said:

The only things that I’ve adjusted (slackened off & re-tightened) are the brass locknuts on the ends of Alt & Az worm drive housings using two 13mm open ended spanner’s and clutch tension knobs on both axis, as recommended by FLO. 

Must admit I found those instructions above a bit confusing as well 🤔

I assume you’ve only tried FLO for the slo mo cables? there’s a few other vendors worth a try, Rother Valley Optics, Widescreen Centre & 365 Astronomy. I believe Astroboot is closed just now. 

Also might be worth a read of the thread @Stu started last year titled Scopetech Zero Mount. 

If u you like I’ll post some pics tommorow of my setup and where I adjusted mine. 

Same here, adjusting the brass lock nuts seemed to do the job, nothing else needed.

[tompato]

Ah okay, that's interesting. If you could show me tomorrow what you adjusted that would be good. So far I have followed the instructions in the maintenance guide ( https://www.firstlightoptics.com/user/products/large/zero.pdf ) and tried loosening the tension screws (1.5 Allen) and then also loosening and then tightening the case screws (2.5 Allen).

Ill attach a photo of the ones I've adjusted below. Whatever I do they are either too tight or too loose so maybe adjusting the nut like you've mentioned will do the trick.

Edited May 26, 2021 by tompato

[tompato]

16 hours ago, jock1958 said:

I assume you’ve only tried FLO for the slo mo cables? there’s a few other vendors worth a try, Rother Valley Optics, Widescreen Centre & 365 Astronomy. I believe Astroboot is closed just now.
 

Thanks for the tip, turns out Wide-screen Center had stock so I've put an order in!

Edited May 27, 2021 by tompato

[jock1958]

Those instructions from FLO make sense now. I haven't adjusted or touched the tension or case screws as yet only the brass adjusting & brass locknuts.

As you probably know its a simple worm gear and worm shaft arrangement very similar to my Skytee 2 Alt Az mount and probably lots more.

Adjusting those tension screws will either increase the engagement of the worm shaft onto the worm gear making it tighter or looser depending which way you turn the tension screws, the brass nuts that I adjusted basically affect the end float of the worm shaft giving you more or less backlash. 

Great result on the slo mo cables you will definitely notice the difference, you might even find things too loose and you will end up re-adjusting things again.

Below some pics of my setup, two 13mm open end spanners to loosen off the brass adjusting & locknuts (notice I filed down the inboard 13mm spanner to get it to fit). Also a pic of a typical worm gear and worm shaft if you are not familiar. 

Edited May 27, 2021 by jock1958

[tompato]

Thanks @jock1958, that makes sense with the adjustment brass nuts. What I'll do is wait til the slow mo cables are here and then see what it's like. I feel like I'll definitely have to tighten the Az at the very least.

It the Alt is still tight with the new cables I'll try adjusting the brass nuts you've mentioned above.

At least with the worm gear it seems like I couldn't have damaged it by loosening off those tension/case screws too much, it seems they must be strong enough to handle turning one another when quite stiff so that should be fine, plus the main clutch moves nice and smooth so I'm sure it's fine.

I've probably worn the case screws out a bit by repeatedly loosening and tightening them but I can always replace them if their heads ever look like they've seen better days.

[jock1958]

You are most welcome @tompato and glad to be of  help. 
Yeh a few people have mentioned that the brass nuts seem to be a bit tight from the factory, apart from that the quality is top notch certainly in comparison to my Skytee 2! 

 

[tompato]

So the slow motion cables arrived, they were great @jock1958, apart from the fact by hand tightening they kept undoing and so I went to tighten it a little bit and this happened (photo attached). To say I'm livid is an understatement, I've only had them for 5 minutes.

[JeremyS]

27 minutes ago, tompato said:

So the slow motion cables arrived, they were great @jock1958, apart from the fact by hand tightening they kept undoing and so I went to tighten it a little bit and this happened (photo attached). To say I'm livid is an understatement, I've only had them for 5 minutes.

You don’t seem to be having much luck with this setup. I hope you can get the slo-mo replaced very soon.