Missing knobs

[Eugene69]

Hello everyone, 

Hope you have all been enjoying the clouds. I recently acquired this tripod and mount with a bresser skylux attached, it's missing a couple of knobs. Can anyone help me identify this mount? Also are the missing bits the slow motion cables??? 

Cheers

[mikeDnight]

It certainly looks like the slow motion flexi cables are what you need. You can get them from FLO. Skywatcher slow motion cables should fit ok.

[Eugene69]

Thanks mike

[Zermelo]

I have the same one.
The manual just refers to it as an "EQ3", but I'm not sure that's particularly helpful.

There's some discussion in this thread.  As @mikeDnight says, the FLO Skywatcher slo-mos should work - just a thumbscrew to engage with the flats on the exposed pin. I found the design a bit of a pain, as I was forever tightening up the screws when they came loose.

[jock1958]

43 minutes ago, Zermelo said:

I found the design a bit of a pain, as I was forever tightening up the screws when they came loose.

I know exactly where you are coming from, I ended up using a penny washer in the slot to give them an extra tweak. 

[Zermelo]

Here's another link to a discussion by someone who has the same scope under a different name:
http://www.jim-easterbrook.me.uk/astro/scope/skylux/

It seems the mount is better described as "EQ-2 like" than "EQ-3 like", though it's more solid than many you'd get with a 70mm.

Oh, and try to be careful when you open out the spreader to fix the tripod legs. The only thing to break on mine was one of the connectors that slides up and down the leg - they seem to be made of a plastic that gets "fatigued" over time. I think it helps if you also push the spreader arms, and don't just rely on opening out the legs. Celestron replacements are almost identical; I managed to pick up some cheap ones at AstroBoot, but I see they have suspended shipping to the UK because of post-Brexit tariffs.

[Eugene69]

On 12/05/2021 at 10:11, Zermelo said:

Here's another link to a discussion by someone who has the same scope under a different name:
http://www.jim-easterbrook.me.uk/astro/scope/skylux/

It seems the mount is better described as "EQ-2 like" than "EQ-3 like", though it's more solid than many you'd get with a 70mm.

Oh, and try to be careful when you open out the spreader to fix the tripod legs. The only thing to break on mine was one of the connectors that slides up and down the leg - they seem to be made of a plastic that gets "fatigued" over time. I think it helps if you also push the spreader arms, and don't just rely on opening out the legs. Celestron replacements are almost identical; I managed to pick up some cheap ones at AstroBoot, but I see they have suspended shipping to the UK because of post-Brexit tariffs.

Thanks zermelo, 

Upon further research i have seen it referred to as a german equatorial mount (gem) which makes sense. I found these 

https://www.microglobe.co.uk/celestron-astromaster-slow-motion-controls-set-of-2-p-13173.html I prefer the look of them compared to the flexible type but I have no experience whatsoever with an eq mount but I am already thinking about motor drives haha

[Zermelo]

3 minutes ago, Eugene69 said:

i have seen it referred to as a german equatorial mount (gem)

Yes, it is a GEM, though that is just the type - there are many individual mounts with that same basic design.

4 minutes ago, Eugene69 said:

https://www.microglobe.co.uk/celestron-astromaster-slow-motion-controls-set-of-2-p-13173.html I prefer the look of them

They look to be the same attachment mechanism, but much shorter. Actually, the original slow-mos supplied with the Bresser are different lengths for the RA and DEC axes, though neither is as short as those. I don't see why they shouldn't work; in fact, they might be slightly better in one respect: I found that one of the Bresser slow-mos would sometimes get in the way of the tube movement, when viewing targets that were in the "wrong" place. It might not foul itself on a shorter control.

10 minutes ago, Eugene69 said:

thinking about motor drives

well the link above shows it can be done. Just the RA axis would be enough for tracking, I've no idea how accurate it would be.

 

[Eugene69]

Maybe why the knobs are gone too

[Eugene69]

5 hours ago, Zermelo said:

Yes, it is a GEM, though that is just the type - there are many individual mounts with that same basic design.

They look to be the same attachment mechanism, but much shorter. Actually, the original slow-mos supplied with the Bresser are different lengths for the RA and DEC axes, though neither is as short as those. I don't see why they shouldn't work; in fact, they might be slightly better in one respect: I found that one of the Bresser slow-mos would sometimes get in the way of the tube movement, when viewing targets that were in the "wrong" place. It might not foul itself on a shorter control.

well the link above shows it can be done. Just the RA axis would be enough for tracking, I've no idea how accurate it would be.

 

For the price of replacement slow mo cables I'm starting to think about wanging an ra drive on it will be more fun for the money

[Alan64]

The mount is not quite an EQ-3, nor an EQ-2; betwixt the two it seems...

You can certainly motorise the RA-axis, but you will need to tweak the DEC-axis once in a while during use, the frequency dependent upon how accurately the RA-axis is aimed at the NCP(Polaris).  A knob that will fit onto the latter, without a cable, will serve.

It may be possible to attach one of the 9V-battery drives on the market to the head; for example...

https://www.firstlightoptics.com/celestron-astromaster-series/motor-drive-celestron-astromaster-geq-93514.html

I have one of those drives.  It comes with two brackets for attachment...

 

Or, a bracket can be customised for the mount, and based on those two; a bit of DIY.  The drive has been used successfully with EQ3-class mounts.  The one thing I like about that type of drive is that the speed can be adjusted.  It's something of a universal drive, and sold under several marques(Sky-Watcher, Orion, Meade).

Now, there are Bresser OEM drives as well, and you can certainly consider those as well. 

[Zermelo]

On 16/05/2021 at 23:44, Alan64 said:

The mount is not quite an EQ-3, nor an EQ-2

Yes, referred to as an "Astro-3" in one of the links, I think.  The mount that the OP (and I) have certainly looks beefier than the EQ-2, though I think I have also seen the same Bresser OTA sold on a lighter mount, similar to the EQ-2 in your picture.

If the OP does get a motor like the one above at FLO, there are several online guides on how to fit them:

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

https://www.youtube.com/watch?v=8or1NOHHZV0

though I see that on the Bresser mount, the fixing point for the motor bracket is not on the same side as the slo-mo attachment point (the RA pin end with the flat), it's on the other side, where the opposite end of the RA axis has the exposed gear wheel and clutch mechanism. The instruction manual mentions the motor attachment points in passing, but doesn't describe the fitting; presumably, though, it expects a motor that engages with the gear wheel, something more like this:

https://www.firstlightoptics.com/sky-watcher-mount-accessories/single-axis-dc-motor-drive-for-eq3-2.html

and fitted like this:

However, that motor (as well as being more expensive) does not appear to feature the fine-control speed adjustment of the EQ-2 version, and I think I've seen other discussions somewhere saying that the number of teeth on the Astro-3 gear wheel does not give the correct rotation speed when driven by that motor. So it might be better to try to mount the EQ-2 motor on the slo-mo side of the mount, as did the final poster in the link above. I think the mounting points he is referring to are the screw holes on the rear shown here:

(this is taken from another thread, where the author has made up his own motor). Another possibility is that you might be able to use the lock screw for the altitude adjustment (which is exactly 80mm from the RA axis, centre to centre) to hold the original bracket supplied with the EQ-2 motor - it is slotted, so it has some leeway, but I'm not sure of the dimensions.

 

Edited May 19, 2021 by Zermelo
can't type