Beautiful Old Mount - Any Info?

[yuklop]

Hi All,

I have got my hands on the beauty shown below. I wonder if anyone has any more info or has seen anything like it? I have already done a gentle restore. Just changed the gaskets to cork, and given it a gentle shine. 

Interestingly, the RA axis is not held in at all, it is just the weight of the mount that holds it in place. The DEC has a block to stop it falling out.

From what I know about the mount: It was originally a Push-to design. It has been retro-fitted with an AWR drive system (not shown in images). I expect I'll change that out for an Onstep system, as its easier to interface that to a PC, and operates with a belt drive and not a gearbox. The AWR documents describe it as a "R. Miller early type", and this fits with the story as I have it so far, in that Rob Miller, of mount making fame, made it back in his Astro Promotions - Luton days, probably not as a production mount, more as an experiment. It is absolutely massive. The mount next to it is a HEQ5 for reference. The RA shaft is 2 inch stainless bar and a 7.5 inch brass worm gear. The whole head weights near 40kg.

I will try and use it for Goto and guiding, but it might be tricky with no axis locking or, even a way to tension the axis (like a Losmandy G11). Perhaps I'll have to try and retro fit some tensioner on the axis if it keeps moving in the breeze.

I'd love to learn more about this mount, and any thoughts on converting the old Push-to style to Goto.

Thanks,

Dan

[Carbon Brush]

Definitely an interesting mount and it looks the business for a heavy scope.

If you get a chance I would be interested to see pics of the AWR goto parts. They made several varieties for different mounts.
I use one on my D6 mount - which is connected by a serial cable and USB/serial adapter to my observatory PC.

Thanks for sharing.

David.

[yuklop]

Hi David,

The AWR system is a micro stepper version. Image attached.

It even has some nice paperwork with it.

[Peter Drew]

I have seen plenty like it!  🙂.  It is a design that Rob and myself developed for mounting large telescopes.  It is actually a rather late Rob Miller mount as he was working on them prior to emigrating to the USA and joining Astrophysics, several of the elements were incorporated in the early Astrophysics mounts.  I made several similar ones for large fork mounted Newtonians and Cassegrains.  I still have one that carries a 12.5" F13.5 Cassegrain.  I was recently donated the largest version that Rob ever made, it has a 4" stainless steel polar shaft!.  It carries a 10.25" F7 Newtonian with an optical window on a massive fork mount.  I have refurbished it but not had chance to try it out.  I'll post some photos as soon as I can.

[yuklop]

Wow, that is fantastic. What a wonderful design it is. I love all the metalwork and engineering on show with this mount - it is superb, and actually the reason I got it. I wonder how many are out there? Very interested to see photo's of any others that are around, and almost surprised that there are even bigger version out there. What was the design payload of the one in the photo, and was that not enough for almost anything already. It has a 24 inch counter weight arm!

And even though it looks fantastic, I do need to get it working and used too. It is destined for installation on my pier, to carry my 12'' lx200 if I can bring myself to de-fork it. I could also add my little refractors, but I think with the mount, more weight would help add some pressure to the RA axis and reduce slip. No idea if slipping is even a problem yet, but I am very much looking forward to finding out.

Edited November 11, 2021 by yuklop

[Carbon Brush]

Thanks Dan. The AWR kit is newer than mine. But essentially the same.
When I bought mine (a long time back) I was impressed by how well it compared to the usual Meade/Celestron/Skywatcher stuff.
Well it remembered the date and time after power off for a start! Even has an oven for the real time clock crystal to help with stability.
Have you considered putting the mount together with the AWR kit? See how it performs before doing serious conversion work?
To me the biggest issue with the kit is the very slow slew. Apart from that everything has impressed.
The kit (in a sub menu somewhere) allows you to adjust acceleration & max slew to cope with different loads.
 

[Peter Drew]

2 hours ago, yuklop said:

Wow, that is fantastic. What a wonderful design it is. I love all the metalwork and engineering on show with this mount - it is superb, and actually the reason I got it. I wonder how many are out there? Very interested to see photo's of any others that are around, and almost surprised that there are even bigger version out there. What was the design payload of the one in the photo, and was that not enough for almost anything already. It has a 24 inch counter weight arm!

And even though it looks fantastic, I do need to get it working and used too. It is destined for installation on my pier, to carry my 12'' lx200 if I can bring myself to de-fork it. I could also add my little refractors, but I think with the mount, more weight would help add some pressure to the RA axis and reduce slip. No idea if slipping is even a problem yet, but I am very much looking forward to finding out.

There should be three equally spaced  grub screws somewhere on the component that carries the RA wormwheel,  these bear on to nylon pads and can be tightened to remove unwanted slippage.   The very large Rob Miller mount that I have was a one-off custom mount.    🙂

[VaguelyAmused]

This is beautiful! I have an incredibly similar mount (I will post it in a different thread to avoid hijacking your own), and it is so nice to see one of its brothers/sisters out there in the wilds and fantastic to get another bit of history about it, thanks Peter!

We (my Dad and I) retrofitted a Sitech Servo drive years ago to ours, but with a recent failure on this it has been changed over to OnStep, you really won't be dissapointed. Its making me want to have a kid just so I have someone to hand mine down to, it feels like a family airlume.

Enjoy the lovely find, and great it is being shown some love.

Edited November 12, 2021 by VaguelyAmused
spelling mistake

[VaguelyAmused]

I suspect your investigations into the mount may have already led you to this, but for a bit more of the history associated with the mount (and the man) if you search on google for rob-millers-astro-promotions-pm1 there is a forum page with pictures and details of the Astro Promotions PM1 mount that is an interesting read.

[yuklop]

Its nice to hear of more such mounts still in the wild. By all means dump photos here, and don't worry about hijacking! If they are in the same place, it just makes it easier for future searchers.

Regarding AWR vs onstep. I have thought about keeping the AWR system and I may well set it up with the AWR first, since it'll take we a while to source and solder the onstep. There will be inherent backlash from the gearbox (although I have to say it is a very nice gearbox!), that onstep won't have and also, onstep is just so good. I have onstepped my LX200 mount, and really like how the system works, now I understand it all. And really, once you've onstepped once, it is a fairly simple conversion. 

I am just excited to get this mount installed, so main decision equipment-wise is whether to defork the Meade 12'' LX200 Classic, that is installed now, or not. I should, as its a lovely tube, but on the otherhand the whole onstepped LX200 works so very well, and was such a lot of work to get working that well, it seems a shame to defork it. I'm sure I can pickup another already deforked 12'' OTA at a decent price and keep the system I have whole for me or someone else in the future. 

Time will tell.

[Mr Spock]

This is how mounts should be - solid and well built. 

[Marvin Jenkins]

1 hour ago, yuklop said:

Its nice to hear of more such mounts still in the wild. By all means dump photos here, and don't worry about hijacking! If they are in the same place, it just makes it easier for future searchers.

Regarding AWR vs onstep. I have thought about keeping the AWR system and I may well set it up with the AWR first, since it'll take we a while to source and solder the onstep. There will be inherent backlash from the gearbox (although I have to say it is a very nice gearbox!), that onstep won't have and also, onstep is just so good. I have onstepped my LX200 mount, and really like how the system works, now I understand it all. And really, once you've onstepped once, it is a fairly simple conversion. 

I am just excited to get this mount installed, so main decision equipment-wise is whether to defork the Meade 12'' LX200 Classic, that is installed now, or not. I should, as its a lovely tube, but on the otherhand the whole onstepped LX200 works so very well, and was such a lot of work to get working that well, it seems a shame to defork it. I'm sure I can pickup another already deforked 12'' OTA at a decent price and keep the system I have whole for me or someone else in the future. 

Time will tell.

I am so jealous of your decision conundrum. What an awful place to be🤣

Marv

[VaguelyAmused]

yuklop for a few pictures, maybe fit the AWR because the drive and mount are from a similar era and having some pictures like that would be brilliant. However, IMHO time has moved on a bit since the AWR. Its still a great system (I actually have an AWR intelligent handset, a grey version, along with two rather large Beacon Hill worm/wheels from an old mount - the guy had his observatory broken into and they took the microstep drive system unfortunately).

Just with modern processors and stepper drivers there is a bit more "freedom", like switching between microsteps to get the best of both worlds, fine tracking and quick slews. No doubt preaching to the converted if you already have one fitted to your LX200 and have more experience than me with it! 

Have fun bringing the mount back to life and enjoy the decision making process behind what you put on it  

[yuklop]

Well, here it is, reassembled and the AWR drives installed. I reckon I’ll probably attach it to the pier with the AWR system and give it a go. Onstep can come later.

 

[yuklop]

To close the show, here are a couple of images of it installed on the pier working with the awr system.

Reckon that little es80apo is about the most overmounted scope in the uk right now 😁

 

Will have to learn how to sync that awr system and use it.

Edited November 19, 2021 by yuklop

[markse68]

such cute little counterweights 😂

[Peter Drew]

Photo of Robs largest mount as mentioned earlier in this thread

[yuklop]

An unusual one.... its a Rob Miller prototype from the end of the 80's modified with Onstep drive control. Here it is happily holding a 14inch classical cassegrain, with 25kg of counterweights. 

A lot more info on this and other mounts in this thread: 

 

 

[johnturley]

The base plate looks the same design as that of the fork mount on my 14in Newtonian which was built and designed by Rob Miller of Astro Systems (Luton), in 1983 (see attached photos), it still has the original RA and Dec motors,  which are still in working order after nearly 40 years!

Although a very substantial and solid mount (I currently have piggybacked on it my Esprit 150 Refractor), it does suffer from the same problem of not being able to lock the axes, necessitating having to rebalance the scope if you attach a heavy eyepiece, barlow or camera. 

Edited July 15, 2022 by johnturley

[johnturley]

[yuklop]

I posted my message in the wrong thread, but its worked out somehow. The base looks exactly like that one, and yes, the axes cannot be locked. They can be made quite stiff though, as mine has 3 large nylon tipped screws on each axis that can be tightened or loosened to set the amount of force required to move the axis.  They are under the black painted cowling on mine, so could be worth digging into your one and seeing if you have them.

[johnturley]

19 hours ago, yuklop said:

I posted my message in the wrong thread, but its worked out somehow. The base looks exactly like that one, and yes, the axes cannot be locked. They can be made quite stiff though, as mine has 3 large nylon tipped screws on each axis that can be tightened or loosened to set the amount of force required to move the axis.  They are under the black painted cowling on mine, so could be worth digging into your one and seeing if you have them.

I do have two of what can be best described as stiffener knobs on the Dec axis (you can see one of them in the 2nd photo), and one on the RA axis. I have replaced the original knobs on the Dec axis with larger knobs (see 3rd photo) but they are still insufficient to hold the scope in place when you insert a heavy eyepiece, camera etc. 

It's interesting that you had your mount upgraded by AWR Technology, I assume that potentially they could do the same with mine (the mount is driven by a mains AC synchronous motor with variable frequency oscillator (by Nigel Groom of Astrotech), and variable speed DC Dec motor). The problem in my case however would be stripping down the mount (which would not be easy), and transporting it to Kent. Ideally if I wanted to go down that route, I would need to find someone who could do it on site, but this would almost certainly be prohibitively expensive. 

Edited July 16, 2022 by johnturley

[yuklop]

The one I got had been previously upgraded with an awr kit. It was a very good job done. I was looking for something a bit easier to integrate with a pc for imaging and had prior experience with onstep, so I took off the awr drives and replaced them with an onstep system. If you are a bit handy onstep could be for you, and the whole thing can be done for a couple of hundred quid.

 

Let me see know if your interested in onstep and I can surely help you out.

[johnturley]

19 hours ago, yuklop said:

The one I got had been previously upgraded with an awr kit. It was a very good job done. I was looking for something a bit easier to integrate with a pc for imaging and had prior experience with onstep, so I took off the awr drives and replaced them with an onstep system. If you are a bit handy onstep could be for you, and the whole thing can be done for a couple of hundred quid.

 

Let me see know if your interested in onstep and I can surely help you out.

Ideally I would like my Astro Systems fork mount upgraded to GOTO facility, but realise that retro fitting encoders to enable this would be prohibitively expensive, even if it was possible at all. The RA drive has a 720 teeth worm wheel driven by a 1/2 rev per minute synchronous motor, and the size of the RA wheel may limit what a stepper motor could achieve when it comes to rapid slewing. 

I currently use a sidereal clock (actually use an app on my phone now rather than the actual clock), in conjunction with the meridian pointer (see attached photos) to find celestial objects which are not visible to the naked eye. I find this more accurate than the GOTO facility on my Celestron 9.25 CPC,  and is an excellent method for finding Mercury and Venus in daylight, which the CPC system cannot readily do. 

I am also more of a planet than a deep sky observer, and my present system can keep a planet at high power in the field of view for over an hour, much better than the CPC mount or the AZ EQ5 (with the ES 127) can achieve, so I couldn't really justify spending a lot of money upgrading the fork mount. 

John