Commercial truss dobs [Archive]

Starkler

27-08-2006, 12:55 PM

This is a last ditch call to see if anyone in Australia makes truss dobs commercially:help:

I know of SDM telescopes who I have heard make very nice obsession clones, but they wont touch anything smaller than 18".

I'm looking for something in the 14 to 16 inch class for reasons that its a size that can be easily transported and set up single handedly, and can be used without a ladder.

Right now I'm looking at getting a 14" Tscope as it seems to be pretty much ideal for my needs http://www.tscopes.com

[1ponders]

27-08-2006, 02:12 PM

Make sure you post how you go Geoff. I think you are not the only one around here that might be interested in a 16" range of truss dobs.

mick pinner

27-08-2006, 03:53 PM

the problem lies in the cost of the primaries (good ones), many people would like a 16" dob but they want to pay in quality telescope terms next to nothing for them.

Starkler

27-08-2006, 04:05 PM

Mick money isnt the issue here , but lack of choices available locally ....read none!

xstream

27-08-2006, 04:20 PM

Try here (http://www.sdmtelescopes.com.au/johnconnellycustomscopes.html)Geoff .
This is off Peter Reads website, apparently this guy specializes in 16" truss dobs.

Starkler

28-08-2006, 07:37 PM

Thanks John, I emailed John Connelly some time ago about his scopes and never got a response .

I got a reply from Ed at Tscopes, and the shipping will be a killer:doh:
Last shipping quote he gave for Aus was $850US:scared:

Of course the customs duty and gst payable after landing here will be on the total price, including shipping :rolleyes:

janoskiss

28-08-2006, 08:20 PM

Just use the $$$ to buy a shed and a bunch of tools and the optics instead and DIY! :D

Satchmo

29-08-2006, 09:56 AM

Yes, or just park your car out of the garage while you build your scope :)You can buy a Chinese router for under $100 , to cut top rings and side bearings. The rest can be cut at a plywood supplier. With the great diversity of ready to go components from Truss connecters to mirror holders to focusers available these days, its not too arduous a job to build a dob and a lot of fun. Plenty of people scattered all over Australia are doing it and you have the pleasure of building something that is unique to you .

Mark

Orion

29-08-2006, 04:39 PM

I agree, build your own Geoff.
It's very rewarding.

AstroJunk

29-08-2006, 05:24 PM

Guys, I've built my own scopes and whilst I'm reasonably practical, I've never been good enough to build anything near the pleasure that I get out of one bought which does the job properly!

More so, I have spent endless hours stuffing around replacing things and ending up spending far more than I would have on a propper scope.

I know some people derive great pleasure from ATMing, and some to the extent that the design is much more important than the view itself. And good luck to them - the design of my own scope came from the ATM community not the pros, so I owe a massive debt of gratitude to all those that stuffed up before me, who wasted time and money by having a go.

Be selfish, go buy one!

Starkler

29-08-2006, 06:09 PM

This is what concerns me. My woodworking skills are rather basic and I have never driven a router in my life. There are basic skills like squaring up wood on a table saw (which I dont have), knowing which side to make your cuts from etc etc.
There would be much to learn before I had the confidence to take a router to an expensive sheet of ply :whistle:

Perhaps a kit with precut pieces might be the way to go.

norm

30-08-2006, 10:31 PM

Hi Geoff,

I feel like I'm in the same predicament as you are in. Although I don't have a scope as yet. My plan is to get a dob, namely a truss type. The 12" lightbridge is still on my agenda, but that said if I have the opportunity to get an Obsession, T/scope deluxe or SDM in the 15-16" range that would be my preference. I don't mind paying for quality.

The damn thing is as you know is the shipping cost, not to mention the GST/taxes makes the whole exercise prohibitive. I don't mind paying for the scope itself but when you add those other charges it takes the whole 'bang for your bucks/dream' away.

If only SDM would come to the party and consider a 15" I'm sure there would be a niche market for them!!!

gaa_ian

30-08-2006, 11:17 PM

Good luck guys, I tried & in the end I was lucky enough to get the 18" beast we have. But I must say it is not a single handed exersize !
The effort is worth it though :D

AstroJunk

31-08-2006, 12:44 AM

Hi Norm,

I've just been talking to Peter about the possibility of building a smaller SDM, and he tells me he can get optics from OMI (http://www.opticalmechanics.com/) to make a 15". He's quite up for the challenge or making a 'reasonably priced' smaller scope as it turns out - even though he's pretty busy with his larger projects. He says to give him a ring on or drop him an e-mail http://www.sdmtelescopes.com.au/contact.html for a chat.

I think it will be very interesting to see how much one would cost in the end, as I'd rather like one myself as a travel scope!

janoskiss

03-09-2006, 09:09 PM

Geoff, I know it might go against every fibre of your being, but how about something like 14" LX200R OTA + beefy EQ mount? Probably costs no more than a custom made ~15" Dobs.

Rodstar

04-09-2006, 07:49 PM

I am not sure that the maths quite add up there. For the 14" LX200R OTA alone, you are looking at $6849 (Bintel's current price). Add an EQ mount to carry that sort of weight, plus freight costs, and you'd have to be pushing $10K. That's what I am getting my 20" truss dob for with OMI Torus mirror from SDM, delivered to my door (interstate).

Starkler

04-09-2006, 08:21 PM

Steve, because of the above reason. Large sct's are somewhat cumbersome to transport and set up.

janoskiss

04-09-2006, 09:09 PM

but they look so compact in photos! :lol:

ballaratdragons

04-09-2006, 09:22 PM

Geoff,

Just an idea mate, but what if you contacted Peter Read or someone who has made nice Truss Dobs before and got a quote to make all of it if you sourced your own mirror.

Mark Suchting or someone else could make you an excellent mirror for your needs.

:shrug: Just a thought.

Darkplague

04-09-2006, 09:54 PM

I am currently building a 16" , with a Mark Suching mirror, and all up it ended up costing about $4000. But that is including the cost of router, various wood tools, sandpaper, finishes.

I would consider the difficulty as 7/10 to construct the Dob.

I don't want to put you off but if you dont know your way around routers and drills and have the basic knowledge to get edges square and such, then I would not attempt a project like this.

Having said that, I am very fussy and had it in my mind that I wanted something of the quality of an Obsession or Starmaster.

If you are half decent with tools you could still build a "good" scope that perhaps wont look as perfect as an Obsession, but still gets the job done.

Another option is an Astrosystems telekit. There is a store in Adelaide that actually gets them in occassionaly. Pm me if you want more details.

Starkler

04-09-2006, 10:42 PM

Im making enquiries with Mr Suchting and Ed Taychart (Tscope) at the moment.
I have emailed Peter Read previously and he wasnt interested. I got advice hat might have changed now.

I could construct a kit, but I wouldnt attempt to build one from scratch for reasons previously stated :ashamed:

I'll give Peter another try. The more options the better :D

AstroJunk

04-09-2006, 10:55 PM

It turns out that the 15" optics are only $600 less than the 18", so there is as good as no difference in price for a much smaller aperture - all of the other components will be the same, just a little less wood and a little shorter truss tubes.

I think that given the costs involved that the 18" does seem to be the practical mimimum size for value for money. And from experience it is quite portable (relatively!) and only requires a single step near the zenith.

xstream

05-09-2006, 11:49 AM

Geoff, I would have to agree with AstroJunk here. The 18" is a very portable scope. A 2 step stool would be all you need; Think of that extra aperture. :thumbsup:

Starkler

05-09-2006, 12:57 PM

I just had a look at the OMI website. Price difference between 18" f4.5 and 15" f4.5 mirrors is $950US !

I have seen and used an 18" obsession and its a big beast of a thing, i would think twice about dissassembling, loading, reassembling on site etc for a casual session away from home. especially single handedly.
A scope thats a bit smaller and lighter is likely to get more use .

I have seen a rough price, and the difference between the 15 and 18 is over $2000. For me its not about price, but usability.

AstroJunk

05-09-2006, 09:28 PM

I think its the diference between 15" OMI and 18" Galaxy Premium (but i'm far from certain).

The only issue with my 20" that I have is the lift into the 4x4 as it's too high for a ramp - that's a 2 strong people lift! otherwise, if you have a waggon or a box trailer then it's no problem for one.

So true. And once you use a Krieg style dob, it's difficult to accept anything else - Obsession continue to sell 12.5" scopes when so many equal aperture dobs can be bought at a third of the price. That says a lot about their design and usabilitty - especially so as the GSO/Lightbridge et al scopes are fine machines themselves!

gaa_ian

05-09-2006, 11:16 PM

I have the same problem of the lift of the 18" into the back of the 4x4 Astrojunk, it is a 2 person lift, also the assembling of the trusses onto the seconarry cell.
I call it "wrestling with the octopus" & I have not succeeding in doing this on my own yet !
But I love the extra aperture :love:

AstroJunk

05-09-2006, 11:28 PM

Luckilly for me, Krieg's truss tube clamps make one person assembly easy.

I hear that the 30" is the easiest of all, due to a light stiffening ring which is fixed when vertical, so the whole scope can be lowered to mount the cage with the scope horizontal. I wouldn't like to try lifting one though!

Starkler

09-09-2006, 12:39 PM

I have been corresponding with Peter Read and he is able to help at a very competetitive price.

Theres some issues to be worked through though as the more I look into it, the more I want to be difficult and get a scope that "fits me" instead of taking a cookie cutter scope solution. This raises other issues with mirror sourcing and getting everything balanced.

I'll let you all know when a decision is made.

wavelandscott

09-09-2006, 04:52 PM

While I have not completed a similar search myself I would expect that creating a "custom" scope is like building a custom anything...

Although there are a number of fabulous handmade/handcrafted professional scopes available they are not "custom" made and will be built from "similar" materials and to a defined pattern...changing the "pattern" could quickly add up...like many, I am curious as to how you go...

Someday I too will move to a slightly bigger scope but I want to keep my feet on the ground...Based on that fact I reckon 15 inches will be about my limit...maybe something a little bigger can be done with a very fast mirror but that "project" is a ways away...

Good Luck!:D

janoskiss

09-09-2006, 10:50 PM

... or you could go a folded 3-mirror Newt if you want to go bigger.

Starkler

14-09-2006, 12:28 AM

This is pretty much what I have decided to do also.

After corresponding with Peter Read of SDM telescopes (http://www.sdmtelescopes.com.au), he has agreed to build a 15" obsession style truss dob for me. Peter has a reputation for excellent workmanship and attention to detail in scope building.

I'll be getting a custom scope made to my specs including feathertouch focuser, encoders and wiring for argonavis, telrad, shroud, dew heater for secondary, powered groundboard and wheelbarrow handles.

My spec is that the eyepiece height at zenith matches my standing eye height. This means that the mirror will be at f4.8 and will be 1.6" thick pyrex provided by Mark Suchting of Deep Sky Optics (http://deepsky.cia.com.au/optics/)

People have asked why not an 18"? and, If your getting a 15, then why not a 16? My answer is that I want the size and weight to be manageable, easily hauled around and set up single handedly. An 18" is a big beast, and if its too much effort to set up it simply wont get used as much

I won't talk about price here, but rest assured that for only a few hundred dollars more than it would cost me to import a kit, build it, and add those goodies, Peter will build one for me far better than I could ever build myself.

This will be my dream scope :love:

Now for the long, long wait......

janoskiss

14-09-2006, 12:41 AM

Glad to hear you've picked a scope even if it does not exist yet. I'm sure you'll love it once it's finished and in your hands. :D

iceman

14-09-2006, 06:19 AM

Excellent news, Geoff.. i'll PM you re price, because something like that would be great in my future.. with an added servocat of course :)

I expect it will be 12-18 months for delivery though?

xstream

14-09-2006, 06:56 AM

Congratulations Geoff, I'm sure you'll be happy with it.
A mirror from one the best; It will blow you away on those rare nights of exceptional seeing.
What time frame did Mark give you?

Starkler

14-09-2006, 08:26 AM

When I first started talking to Peter, he said he had a lot on his plate and gave an initial date of "early next year" . Then I asked Mark and he said "about four months", so my guess is something like 6 months?

I should have set the wheels in motion a few months earlier :whistle:

wavelandscott

14-09-2006, 09:17 AM

[QUOTE=Starkler]

My spec is that the eyepiece height at zenith matches my standing eye height. This means that the mirror will be at f4.8 and will be 1.6" thick pyrex

People have asked why not an 18"? and, If your getting a 15, then why not a 16? My answer is that I want the size and weight to be manageable, easily hauled around and set up single handedly. An 18" is a big beast, and if its too much effort to set up it simply wont get used as much
QUOTE]

Starkler,

Congratulations on what I think is a fine choice (from description) and matches my thinking very closely in terms of size and manageability...you must be a real smart guy :thumbsup:

Good Luck!