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DobStuff Comments - Building from the Kit and Using in the Field

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#1 brentknight

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Posted 22 October 2020 - 04:33 PM

I'm considering rebuilding my 14" Orion with a kit from DobStuff.  I've heard nothing but good comments about Dennis and his business so I am seriously considering this option.

 

At this point, I'm interested in hearing from people who have used the kit and also anything about how these telescopes perform in the field.  Things like what are the biggest issues building one of these and what should I look out for.  How do they work with dew (a big concern here in the south), how stable and easy to track are they, what modifications are done to them to improve them...

 

Any information/comments/suggestions are welcome.


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#2 Jon Isaacs

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Posted 23 October 2020 - 12:26 AM

It's bed time but just a quick question:

 

Are you thinking you can retain the GOTO?

 

Jon



#3 Pinbout

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Posted 23 October 2020 - 09:11 AM

I don't own one but have played with one, great scope bodies....

 

If I didn't build my own, I wouldn't hesitate to buy his structures...

 

I think its a unique, great design.

 

you can't go wrong.

 

worried about dew or stray light... sew a lycra shroud... if he doesn't offer that.


Edited by Pinbout, 23 October 2020 - 09:12 AM.

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#4 brentknight

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Posted 23 October 2020 - 10:07 AM

It's bed time but just a quick question:

 

Are you thinking you can retain the GOTO?

 

Jon

Jon,

 

My main reason for rebuilding is because the Go2 no longer works.  The structure is way overbuilt - especially if I'm not going to use the motors or the clutches.  I'd like to get the weight down, the eyepiece height to a point where I'll never need a step-ladder and I want smooth, manual motions and excellent balance.  I don't have any issues with the optics or other mechanicals.


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#5 Jon Isaacs

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Posted 23 October 2020 - 10:26 AM

Brent:

 

My Dob Stuff is very early, one of the first ones if not the first.

 

If I were doing it over, I'd choose the truss with a dual ring upper cage.

 

Jon


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#6 brentknight

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Posted 23 October 2020 - 11:01 AM

Wow...that option would be more than I paid for the entire telescope originally.

 

What are the weaknesses with the strut design?  Would it make any sense to go with the dual upper cage with the struts? 



#7 Jon Isaacs

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Posted 23 October 2020 - 01:13 PM

Wow...that option would be more than I paid for the entire telescope originally.

 

What are the weaknesses with the strut design?  Would it make any sense to go with the dual upper cage with the struts? 

 

Struts are in bending and inherently less stiff than trusses. A single ring is also in bending.  You don't see large Dobs and RCs with struts. 

 

Dobstuff sells a string kit. I went much further, my scope has six 0.25" aluminum rods with turnbuckles to tension them to triangulate the struts. 

 

Dobstuff Finder Mount 2.jpg

 

A single ring can be stiffened dramatically by doubling it's thickness and laminating the two pieces. 

 

As I said, my scope was one of the first. I can only speak from my experience and the path I took to get the scope to where it is today,  13 years later. Others may have different experiences. 

 

Jon


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#8 Jon Isaacs

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Posted 23 October 2020 - 01:54 PM

Brent:

 

I looked up the Orion 14 inch XXG.

 

The OTA weighs 64 pounds, the base, nearly 100 lbs. Why not build a new base for your OTA, it could include large diameter bearings for the OTA?

 

Dennis could build you a base.

 

Jon


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#9 brentknight

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Posted 23 October 2020 - 03:15 PM

I had though to do that.  It would solve the flex/dew problems and would be cheaper.  Maybe Dennis could figure out how to add larger alt bearings (getting rid of the plastic bits) to the steel LTA.  I'm talking to him now...I'll ask about it.



#10 stargazer193857

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Posted 23 October 2020 - 06:56 PM

Brent:

I looked up the Orion 14 inch XXG.

The OTA weighs 64 pounds, the base, nearly 100 lbs. Why not build a new base for your OTA, it could include large diameter bearings for the OTA?

Dennis could build you a base.

Jon


Wow. Not for me.

#11 brentknight

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Posted 23 October 2020 - 08:01 PM

Wow. Not for me.

I guess I'm old school.  My other Dob is a solid-tube 10" made of Sonotube, so I'm no stranger to heavy telescopes.  And if the weight is well distributed and the telescope is built well - capable of smooth hand-motion, minimal wiggles and can hold balance, I have no problems with it.  Both telescopes live in the garage and can be wheeled out to the driveway in 5 minutes.  Getting rid of the extra bulk and hassle of the Orion's electronics will make moving and setting it up a breeze.  I'd like to do something within reason to make this a usable telescope again - otherwise it will just sit in the corner collecting dust.



#12 Tyson M

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Posted 23 October 2020 - 09:00 PM

I'm considering rebuilding my 14" Orion with a kit from DobStuff.  I've heard nothing but good comments about Dennis and his business so I am seriously considering this option.

 

At this point, I'm interested in hearing from people who have used the kit and also anything about how these telescopes perform in the field.  Things like what are the biggest issues building one of these and what should I look out for.  How do they work with dew (a big concern here in the south), how stable and easy to track are they, what modifications are done to them to improve them...

 

Any information/comments/suggestions are welcome.

I found Dennis extremely pleasant to deal with and the kit turned out amazing.  Highly recommend dobstuff.


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#13 Pinbout

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Posted 23 October 2020 - 09:28 PM

Is that a f4.4?



#14 iKMN

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Posted 23 October 2020 - 09:45 PM

I had Dennis build me a dob last year.  I have a 13.1 inch and could not be happier.  I have the strut version with a single ring.  I am happy with mine it’s F4.5 so probably shorter than your 14.  The main thing I like is the weight savings.  It’s lighter than my old 10” scope it replaced by over 25lbs.  The scope is practically almost grab and go as far as I’m concerned.   The price is not cheap but I think Dennis has found a niche price point between the premium makers and the mass produced stuff.  I have a nice 8” quartz mirror here at the house I was going to have Dennis build me a grab and go with but the 13 he built me is so light weight and ergonomic I don’t know what to do with that mirror.  I really couldn’t be happier for the money.  I’d do it again but he built me such a good scope first time around I don’t need to do it again.

 

cheers

 

k


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#15 brentknight

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Posted 23 October 2020 - 09:49 PM

Is that a f4.4?

It's F4.6.



#16 brentknight

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Posted 23 October 2020 - 10:14 PM

I had Dennis build me a dob last year.  I have a 13.1 inch and could not be happier.  I have the strut version with a single ring.  I am happy with mine it’s F4.5 so probably shorter than your 14.  The main thing I like is the weight savings.  It’s lighter than my old 10” scope it replaced by over 25lbs.  The scope is practically almost grab and go as far as I’m concerned.   The price is not cheap but I think Dennis has found a niche price point between the premium makers and the mass produced stuff.  I have a nice 8” quartz mirror here at the house I was going to have Dennis build me a grab and go with but the 13 he built me is so light weight and ergonomic I don’t know what to do with that mirror.  I really couldn’t be happier for the money.  I’d do it again but he built me such a good scope first time around I don’t need to do it again.

 

cheers

 

k

It sounds like he does a very good job.  I've talked a bit with him and he's been very quick to answer questions and provide suggestions.

 

Is that your scope in your profile picture?  Nice.  Can you give me some idea about how it moves in alt/az?  How well does it track?  Anything you would change about it?

 

He is a bit pricey that's true.  But I figure the personal contact and a custom build is worth a little more.  And even with this rebuild, I'll still be under the cost of this telescope if I'd bought it new.

 

I'm leaning toward keeping my existing OTA and having Dennis build me a new base and altitude bearings.  I figure replacing the pressboard with birch and getting rid of the motors will cut 50 lbs (about 1/3 the total).  And I'll keep the more rigid trusses and full upper tube and still be able to use my existing shroud and the Orion bags.


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#17 Pinbout

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Posted 23 October 2020 - 10:21 PM

 

And even with this rebuild, I'll still be under the cost of this telescope if I'd bought it new.

Stop thinking like that. Totally different animals so comparing $ is conflating issues. 



#18 brentknight

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Posted 23 October 2020 - 10:30 PM

I guess I don't understand what you're saying?



#19 Jon Isaacs

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Posted 24 October 2020 - 04:12 AM

I had Dennis build me a dob last year.  I have a 13.1 inch and could not be happier.  I have the strut version with a single ring.  I am happy with mine it’s F4.5 so probably shorter than your 14.  The main thing I like is the weight savings.  It’s lighter than my old 10” scope it replaced by over 25lbs.  The scope is practically almost grab and go as far as I’m concerned.   The price is not cheap but I think Dennis has found a niche price point between the premium makers and the mass produced stuff.  I have a nice 8” quartz mirror here at the house I was going to have Dennis build me a grab and go with but the 13 he built me is so light weight and ergonomic I don’t know what to do with that mirror.  I really couldn’t be happier for the money.  I’d do it again but he built me such a good scope first time around I don’t need to do it again.

 

cheers

 

k

Did you ever check the collimation shift moving from the horizon to the zenith?

 

Jon



#20 Jon Isaacs

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Posted 24 October 2020 - 04:15 AM

Wow. Not for me.

 

Is it the weight?  

 

I have no problem with a 70 lbs mirror box.  But then I am 72 years old.. and definitely am not as strong as I was when I was a young buck like you.  

 

I am old school.  If it ain't broke, don't fix it.  As far as I can see it's the mount that's the problem, not the OTA.  

 

Jon


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#21 stargazer193857

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Posted 24 October 2020 - 08:58 AM

Is it the weight?

I have no problem with a 70 lbs mirror box. But then I am 72 years old.. and definitely am not as strong as I was when I was a young buck like you.

I am old school. If it ain't broke, don't fix it. As far as I can see it's the mount that's the problem, not the OTA.

Jon


I have an old elbow injury. I can easily lift the weight of an 8" dob and carry it around the yard. But my elbow will hurt for days afterward.

Also, I don't like waiting for DSO to come out from behind a tree. I prefer to pick the scope up and dodge the tree.

So 150 pounds, even in 70 pound pieces, is not for me. Before my injuries, I'd carry a 150 pound person or roll of fabric no problem.
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#22 brentknight

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Posted 24 October 2020 - 10:33 AM

I have an old elbow injury. I can easily lift the weight of an 8" dob and carry it around the yard. But my elbow will hurt for days afterward.

Also, I don't like waiting for DSO to come out from behind a tree. I prefer to pick the scope up and dodge the tree.

So 150 pounds, even in 70 pound pieces, is not for me. Before my injuries, I'd carry a 150 pound person or roll of fabric no problem.

Regardless of the weight of the telescope, from my observing site I don't normally have that option.  I have to dodge streetlights and I have a single spot in my driveway where they are all blocked.  If I want to view more to the south, I have to move down the driveway and bring out a couple light-shields to block the lights on the street.

 

I get the weight thing though, but the only time I would be picking up that weight is when putting the telescope in the vehicle to go to a remote site.  My 10" has wheels attached to the base, and the 14" moves with a hand-truck.  But with an overall telescope that weighs 50 lbs less and 6" shorter, it should be much easier.



#23 lphilpot

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Posted 24 October 2020 - 10:43 AM

I bought a 12" DobSTUFF two years ago, knowing I'd have to dew-proof it (I'm in Louisiana). It's worked out fine, even without using my DewBuster I can observe for quite a while. I did a write up on CN with lots of photos, but apparently my ISP (Suddenlink) has somehow broken access to all of them - None are visible on the post. :(  Nice job Suddenlink, again...  :(

 

https://www.cloudyni...t-to-the-swamp/


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#24 iKMN

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Posted 24 October 2020 - 11:35 AM

It sounds like he does a very good job.  I've talked a bit with him and he's been very quick to answer questions and provide suggestions.

 

Is that your scope in your profile picture?  Nice.  Can you give me some idea about how it moves in alt/az?  How well does it track?  Anything you would change about it?

 

He is a bit pricey that's true.  But I figure the personal contact and a custom build is worth a little more.  And even with this rebuild, I'll still be under the cost of this telescope if I'd bought it new.

 

I'm leaning toward keeping my existing OTA and having Dennis build me a new base and altitude bearings.  I figure replacing the pressboard with birch and getting rid of the motors will cut 50 lbs (about 1/3 the total).  And I'll keep the more rigid trusses and full upper tube and still be able to use my existing shroud and the Orion bags.

Yes that's it in the profile pic.  I think it moves great in alt/az, very smooth - better than my lightbridge or es. No problems at all tracking - but highest power used was 5mm Nagler.  So that's x 340 approx.  You get what you pay for.  I have friends in the club with premium dob scopes that I've used - not just looked through.  It's not obsession or starstructure but it's half the price or less.  About the only issue is when I take out or put in the 31N I need to move the counterweight that is on a strut.  Where the counterweight needs to go depends on the angle of the scope.  I don't always find the sweet spot.  Also, I do have some collimation shift when moving the scope in alt\az.  Every mass produced dob I've owned before had some collimation shift.  It's less with the dobstuff but it's there.  Maybe a few MM with a laser when I tested.  But now I use a cheshire and sight tube mostly.   I've had commercial mass produced dobs where the return beam shifted almost out of the crosshair window in the laser collimator when checking this and those were truss.   So I am very pleased with this compared to the scopes this replaced. I don't go around with my laser at star parties and check my club mates Obessions and Starstructurers for collimation shift so I don't know what or how much is acceptable?  Maybe it's a deal breaker for some.  Obviously the 'flex' it's there when or if I look really low.  Usually, I have to refocus a hair if I move the scope a great difference in alt\az..  To me the weight savings is worth it and the views are still ok because I mostly look at galaxies and globulars with the scope and the collimation is 'good enough' for me.  If I wanted a stiffer scope I would go with the double ring and trusses, but "for me" I am happy with the struts\single ring and the scope weighs under 50lbs (I have a thinner mirror too). 

 

As far as changes, issues:

 

#1  Spend the money and get the struts or trusses powder coated black - I did not and due to sometimes traffic lights (rare where I live) I get reflections off the silver struts.

 

 

#2 Well let me just say FIRST Dennis did me right so what I say next is not a complaint about my scope:  I was a bit concerned about the optics originally. It's a Coulter 13.1 mirror and I knew what I was getting into with that so NO blame what so ever towards Dennis even though he sold me the mirror.  No history on the mirror but it had new coatings.  I had a lot of problems in the beginning and some NOT so great views and I do have a Paracorr2.  I am talking astigmatic stars and the views were so bad that my 80mm ED put up nicer planetary images (last year).  Luckily I have some good club mates and I narrowed my visual problems down to #1 running my secondary dew heater too hot causing astigmatism  #2 My laser is out of collimation   So once I got that figured out everything is fine - I am getting pinpoint stars with my P2 and just wonderful sharp planetary views this season so far.  

 

The last thing and this is a compliment - I "think" I should have had Dennis build me a bigger scope cause this is so easy to setup.  I "think" if I could have done it over I would have tried to score a 15 or 16 mirror and have Dennis build me a scope.  That's really my only regret - "I think".  But when talking with Dennis I told him I wanted the biggest scope I could be seated with and want to haul out every night and he delivered.  It's really a perfect size 'for me" hassle factor and all no matter what "I think".

 

good luck with a decision

 

cheers

 

k


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#25 brentknight

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Posted 24 October 2020 - 11:57 AM

I bought a 12" DobSTUFF two years ago, knowing I'd have to dew-proof it (I'm in Louisiana). It's worked out fine, even without using my DewBuster I can observe for quite a while. I did a write up on CN with lots of photos, but apparently my ISP (Suddenlink) has somehow broken access to all of them - None are visible on the post. frown.gif  Nice job Suddenlink, again...  frown.gif

 

https://www.cloudyni...t-to-the-swamp/

Len,

 

That was a great post - I just wish I could see the pictures...  I'm even more convinced now that keeping my OTA is the better option for me.  I've had the telescope almost 2 years now and only once did the secondary dew over.  To be honest, I've never checked collimation between zenith and horizon.  I've usually just set it at the beginning of the session and then only messed with it if I saw issues.  I just picked up a Glatter laser/tublug so I will be checking the next time I'm out with it...




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