DiskMount?

[jetstream]

Im looking for a mount with encoders that will work through frost and ice in very cold temperatures. The DiskMount from Florida looks like a good set up for my conditions.

Anyone use the DM6/DM4?

Other mount suggestions welcome. Gerry

[old_eyes]

Got a link? Never heard of that one.

[jetstream]

11 minutes ago, old_eyes said:

Got a link? Never heard of that one.

http://www.discmounts.com/dm6_head.html

[markse68]

There's also Desert Sky Astro your side of the pond

http://www.desertskyastro.com

Mark

[Space Hopper]

@jetstream Are you in the US ?

Tom Peters is a gent and a pleasure to deal with.

I've had both and still use my DM-6 as my main alt-az option (with encoders / Nexus DSC) Its a treat to use and on something like a Planet or Losmandy HD tripod, a very stable setup indeed.

Of course, we now have the Rowan AZ100 (UK based) which is every bit as nice and can even be motorised if you wish. It also has a dual scope option.

I think they are both beautiful mounts, but like most things today, rather expensive.......

[jetstream]

4 minutes ago, Space Hopper said:

Are you in the US ?

Thanks Rob, I'm in Canada right on the border and have a legal US shipping address and can get things delivered in 3 days max. I was looking at Diskmount for a few reasons, one being the cold. The big teflon bearings might be very resistant to the cold- I find that anything too precisely made can have issues in the cold... such as gears etc.My AZEQ6 is useless in the cold unless I use it manually.

The DM6 handles your excellent TEC 140 easily? Easy to adjust and holds well with different EP weights? I use a Vixen 42mm LWW as my heaviest really then switch to the likes of Delos and Naglers, with the nod to the latter in the fracs.

Would a DM4 handle the TSA120? I'm thinking maybe not. I just called DM but are away till Monday, prob spring break

Thanks gerry

[Space Hopper]

I would say a 140mm refractor is about the limit of the mount, and thats assuming a Planet type tripod.

A bigger refractor would be a no no for me.

Its also designed (the DM-6) for SCTs up to 11" I've used an 8" Celestron and that was easy.

Remember with a long tubed refractor you'll soon be doing contortions on the floor if you want to observe high up stuff. I would stick to 1000mm focal lengths max.

I've never had any issues in the cold. The DM6 is never affected by it. Slewing and manually tracking is easy all of the time. I can manually track Jupiter at 200x quite happily for minutes at a time. It becomes second nature.

But I think a TSA120 would be a bit too much for a DM4 and would only consider that if you had a smaller scope 80 - 100mm sort of size.

Shout up if you want any photos ? I'll see what i have to give you some idea of setups etc.

 

 

[jetstream]

7 minutes ago, Space Hopper said:

Remember with a long tubed refractor you'll soon be doing contortions on the floor if you want to observe high up stuff

That was me on M81/M82 the other night lol!  Sure appreciate the truss dobs for that stuff. Sounds like the DM6 would be great and in the cold as well. If it handles the TEC 140 the TSA120 should be good on it too, the DM4 is out in my mind now, thanks.

 

8 minutes ago, Space Hopper said:

Shout up if you want any photos ? I'll see what i have to give you some idea of setups etc.

Most definitely, thanks Rob

[ONIKKINEN]

1 hour ago, jetstream said:

http://www.discmounts.com/dm6_head.html

Link doesn't seem to work for me.

57 minutes ago, jetstream said:

The big teflon bearings might be very resistant to the cold- I find that anything too precisely made can have issues in the cold... such as gears etc.My AZEQ6 is useless in the cold unless I use it manually.

My AZ-EQ6 is not a particularly good copy but it doesnt seem to be all that picky about cold weather - as in i see no change in performance after having just set up and after having allowed the mount to cool down to ambient which is on both sides of -10c this time of year. Maybe yours could use some servicing?

The RA axis in mine was particularly tight when i got it, the locknut that holds the entire axis in place was put in way too tight, like an impact wrench tightness or something. Was really difficult to get out but once i did it started rotating much smoother. Still not butter smooth and balancing is a bit of guess work on the RA axis but much better.

[jetstream]

2 hours ago, ONIKKINEN said:

Maybe yours could use some servicing?

Its basically new, not even a few hours on it.

[ONIKKINEN]

33 minutes ago, jetstream said:

Its basically new, not even a few hours on it.

All the same, Skywatcher mounts are really rough out of the factory. I only used mine a couple of times before putting in new bearings and better grease.

[jetstream]

1 hour ago, ONIKKINEN said:

I only used mine a couple of times before putting in new bearings and better grease.

Theres the difference, I still have the factory grease in there and bearings. I'm still looking for soft silicone rubber cables.

[Louis D]

I remember someone using a long 6" refractor on a DM-6 at a local star party.  It worked fine with it until you wanted to change eyepieces without losing your target.  It has no axis clutches, so you had to carefully keep the scope from nosediving while swapping heavy eyepieces (2+ pounds) in and out.  That's one of the reasons I upgraded from my DSV-1 to DSV-2B mount.  I love the latter's axis clutches while swapping eyepieces.

[jetstream]

39 minutes ago, Louis D said:

I remember someone using a long 6" refractor on a DM-6 at a local star party.  It worked fine with it until you wanted to change eyepieces without losing your target.  It has no axis clutches, so you had to carefully keep the scope from nosediving while swapping heavy eyepieces (2+ pounds) in and out.  That's one of the reasons I upgraded from my DSV-1 to DSV-2B mount.  I love the latter's axis clutches while swapping eyepieces.

This was one of my questions ie how much weight imbalance will the 6" bearings hold- thanks Louis!

[Space Hopper]

2 hours ago, Louis D said:

I remember someone using a long 6" refractor on a DM-6 at a local star party.  It worked fine with it until you wanted to change eyepieces without losing your target.  It has no axis clutches, so you had to carefully keep the scope from nosediving while swapping heavy eyepieces (2+ pounds) in and out.  That's one of the reasons I upgraded from my DSV-1 to DSV-2B mount.  I love the latter's axis clutches while swapping eyepieces.

There is that Louis, and it can be more of a problem with heavy 2" eyepieces. 

It can also be exacerbated a bit with a long focus tube : mine is 4.5" (115mm) - raking it right out can obviously cause imbalance issues.

Getting a good balance to start with is key, and i have always had the altitude friction dialled in quite a bit further than the azimuth, just so it holds its position better.

If it does start to move, i've not done my balancing well enough, so just loosen the saddle knobs a bit and move the scope back a cm or so.

I also binoview mostly, so only have 2 fairly light 1.25" eyepieces to contend with.

Clutches are a useful feature, no doubt,(like on the AZ100) but the DM6 doesn't really need them. Same as it doesn't need counterweights either.

 

For me the best thing about the DM6 is the freedom and simplicity it gives.

No CWs, no wires, no motors, and  easy panning with the long handle.

The Nexus is a joy to use. I can push to an object in seconds, then look at something else on the opposite side of the sky again, in a few seconds.

Heres a few piccies....

DM-6

4" scope on board here :

 

4" and 5.5" scopes side by side on the DM4 / DM6

Heres the DM-4

And with 4" scope doing some solar.

I wouldn't dream of putting anything bigger on a DM4. It was just used for easy grab & go, and had no encoders or DSC

Current setup. I've since upgraded the Uni tripod you see here to a Planet which is a big improvement.

Both the DM-4 and 4" scope you see above have since been sold.

Lastly, check out the Rowan AZ100. This was an early model demo-ing at a trade show.

The AZ100 is something else, just a beautiful bit of kit, and now has a motorisation option if that appeals.

I have an astro buddy with this setup and its very impressive indeed.

My DM6 is a 2014 purchase, so i'm pretty attached to it.  UK users a few and far between and i like something unusual in this hobby that's a rarity. I don't think i'll be selling it any time soon.

The AZ100 is much newer and only been around the last 3 or 4 years.

If i was starting from scratch now, i'd opt for the AZ100.

Hope that helps Gerry. Clear sky's 🙂

 

Edited March 15, 2023 by Space Hopper

[jetstream]

@Space Hopper Thank you Rob! You have very good equipment, great info on all this- now comes decision time...

[Space Hopper]

If you want to look more in depth at The RA AZ100 i would do so.

I think your closest north American dealer would be Deep Space Products.

I think they are based in Phoenix, AZ 

[John]

I have not used a Diskmount but they do look very impressive and seem to have some very satisfied customers judging by remarks on here and that other forum 🙂

I have used a couple of the Rowan AZ100's though and even though they were beta-test versions the quality of engineering and operation were very apparent to me. With the further testing by @Stu and others and improvements made by Rowan on the back of that I reckon the production Rowan AZ100's are truly superb high capacity alt-azimuth mounts. 

As it happens, personally I ended up with a T-Rex mount though for my largest refractor (130mm F/9.2 triplet). These are long out of production now but I've no doubts that the AZ100 does an equally good job and of course Rowan are still around supporting and improving their products.

 

 

Edited March 16, 2023 by John

[jetstream]

@John Do you think or have you heard if the AZ100 would hold the likes of a TEC 160 steadily?

[John]

3 minutes ago, jetstream said:

@John Do you think or have you heard if the AZ100 would hold the likes of a TEC 160 steadily?

It's difficult for me to say - I've never used a TEC 160. @Stu would be a better person to ask I think - he has a lot more experience of the AZ100 than I have had.

@GavStar has a TEC 160 but he went for the TTS 160 from TrackTheStars. 

 

[Space Hopper]

Someone in the US has done it and said it was ok.

Its over on CN somewhere if you delve through the refractor forum

Personally I think it would be pushing it , but with something like a Losmandy HD underneath it, probably ok. The DM-6 has a quoted 40 Lbs capacity.

Also a 160mm refractor is a big big scope. And soooo expensive !!  For me 140mm's is as big a refractor as I can sensibly manage, and i'm not getting any younger.

 

[jetstream]

4 minutes ago, Space Hopper said:

and i'm not getting any younger.

Me neither!

But hey this could be my last chance to manage one

[John]

9 hours ago, jetstream said:

Me neither!

But hey this could be my last chance to manage one

That's one of the challenges isn't it - by the time we get the means to acquire the equipment that we have dreamed about, old age catches up and actually using it becomes quite a challenge 😁

 

[jetstream]

12 hours ago, Space Hopper said:

I think your closest north American dealer would be Deep Space Products.

Thanks I just looked them up, will call later.

[TakMan]

Just to chime in - as you’re that side of the Atlantic…

You could also look out for a second hand Half Hitch FTX-V2 or V1 (with or without the upgrades).

That would give you the late Charles Riddle’s ‘2-axis’ balance. That would negate some of the eyepiece / weight changes and also has axis locks.

Like the DiscMount, well made (much lighter though), scope positioned over the tripod centre-line, encoders for push to…

Just a thought. Like ‘SpaceHopper’, I’m happy with my own buying decision - the Half Hitch Nova Hitch mount (would also work for you), like the fact it is a ‘bit different’ and does what I wanted - free flowing and graceful movements without stiction.

Just an alternative idea based on your location…. if you can find one - although they do come up second hand as I get notifications via the old Yahoo group!

Damian

Edited March 16, 2023 by TakMan