Author Topic: Choosing a custom Dob Maker  (Read 499 times)

maogrinjorli

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Re: Choosing a custom Dob Maker
« Reply #15 on: February 02, 2018, 02:20:32 PM »
Obsession falls to second rate?

Say it ain't so!

tradneedcoegen

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Re: Choosing a custom Dob Maker
« Reply #16 on: February 02, 2018, 08:44:49 PM »
Quote
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I got it down to 2 scopes. JPAstrocraft or StarStructure. I went with StarStructure because it's all metal.

These two guys are making the highest quality dobs in the US at the present time. I was so impressed by John Pratte's design that I had him make some components for my 32" and bought them back to Australia for fitting into my SDM dob.

John's design and engineering are what separates his dobs from everyone else. If I lived in the US and wanted a dob constructed of wood, John would be making my dream scope.
What exactly about the JPAstrocraft engineering is so unique? Legitimate question. I know he uses good cells but that isn't exactly unique.

New Moon and Teeter have a few small interesting innovations that I like - like the collapsible trusses (NMT), truss ring design (teeter), and the new hybrid design (NMT).

But overall, all of them seem very much the same design as the classic obsession.

Compare these scopes to Oberon's 16" Merope, and (imo) all of these options are more or less the same in terms of "design and engineering".

This leaves me thinking that the major difference is in small "fit and finish" details, which of course can be important but are not really design/engineering differences.

blasbunmena

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Re: Choosing a custom Dob Maker
« Reply #17 on: February 08, 2018, 03:38:57 AM »
Back to the O.P.'s question.

I picked Teeter because, among other things, he will build a high-quality scope around YOUR mirror. He will put the focuser and finder scope where YOU ask him to. The build is very attractive, rock-stable, and easy (fun) to use. I liked the boundary fans, and the Truss "Ring" to allow quicker setup/take-down. I am dis-inclined towards metal builds, as cold temps from metal on my hands (even gloved) in the winter months is disagreeable to me. Wood and fiber are much kinder in the winter. Rob was also very communicative during the build, and he also allowed me some last-minute upgrades just before shipping. I won't say those last two things made me choose Teeter, but they might influence any future scope build I might consider.

nalchsilnighnul

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Re: Choosing a custom Dob Maker
« Reply #18 on: February 09, 2018, 11:34:17 AM »
Research, research, research online as well as looking through scopes from various makers led me to a list of criteria.
I insisted on a fast mirror that would allow me to avoid using a ladder. and to remain seated for most observing
I wanted the biggest fast mirror that would fit, fully assembled, through the conventional sized door to my climate controlled storage shed.
I wanted input on design features unique to my personal needs such as left sided focuser, dew heater on secondary, built in SIPS, integrated wheels, ability to run it with Nexus DSC and a few other things. I am partial to the look of wood.

This led me to identify Mike Lockwood as my preferred mirror maker (not that there might not be others)
Mike works frequently with John Pratte ( their shops are close to each other) and together they have done significant work on mirror support and mirror cooling systems. They were both very receptive to questions via email. Liking what I learned so far, I planned a weekend trip to visit these men and their shops. They were supremely accommodating, answered numerous questions and showed me details of their work. Unfortunately conditions did not favor viewing that night.

After a few hours, we decided that a 20" F 3.0 would meet my needs. I left with that plan in mind, needing to decide only mirror substrate and of course if I was really going to spend that much on a hobby (I am half Scottish, so these decisions require thought  ).

John contacted me after my visit to follow-up and say he had found a different set of wheels that would allow me to get a 22" scope through a 36" door, so after a bit more thought I went for it. this is the biggest scope I can get without redesigning the building. It is a simple roll-out to the yard for viewing then roll back in when I am done. No assembly or disassembly required. No wheel barrow handles required since John's integrated wheels allow the scope to work as if it has an integrated hand-truck. The scope holds collimation well, needing only a tiny tweak after rolling it down a ramp and 20-30 yards across the "yard" (bumpy). When needed, the scope breaks down easily for transport to darker skies. It takes maybe 20 minutes to assemble in the field (no help needed).

John was kind enough to deliver it to my home (about 500 miles). He spent a few days making sure all was right, observed with me and pointed out all I needed to know about the scope. We toured the Barber Motorsports Museum and enjoyed a great time together. Since receipt, I have been ecstatic with the scope. It rocked at OkieTex and put up views that drew all positive comments throughout the week (and I had the smallest scope in our group).

I am certain that most if not all of the builders noted here are top quality. To most of us this is a once in a lifetime purchase and I think that introduces some degree of subjectivity. I like to think of myself as having a scientific, objective mind, but I also knew I did not want to put down this much money and be plagued with "what ifs". What if I had gone bigger or smaller? What if I chose a different mirror substrate? What if...?

By getting to know these two men of whom I had read so many praises, I can say that it was ultimately a very personal decision. I feel confident that I have the best scope for me. There is no buyer's remorse. I feel that my hard earned money has been well spent and I am thrilled with the way the scope looks, handles and puts up views. There have been no second thoughts and no regrets.

I wish the OP luck in working through this challenging but important decision. I hope that the process is as enjoyable as I found it to be and the result is as personally satisfying. Scope details are in the link in my signature.