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Dynamax 8 SCT Restore

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#26 Mitrovarr

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Posted 10 September 2020 - 02:55 PM

If you were splitting Izar with it, that's a good sign about the optics. I have heard the early ones were better.
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#27 RDFox

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Posted 11 September 2020 - 09:01 PM

Started media blasting some of the base. I think I’m going with the black semi wrinkle paint for the base and forks.

 

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#28 Maximumron

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Posted 11 September 2020 - 09:15 PM

If you were splitting Izar with it, that's a good sign about the optics. I have heard the early ones were better.



#29 Maximumron

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Posted 11 September 2020 - 09:28 PM

I believe they're very good optics.
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#30 Gil V

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Posted 13 September 2020 - 05:35 PM

Maximumron, pm me with specific questions.

Edited by Gil V, 13 September 2020 - 05:36 PM.


#31 Maximumron

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Posted 13 September 2020 - 08:31 PM

Gil V., will do thank you for the offer.

#32 RDFox

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Posted 29 December 2021 - 09:43 PM

250992F8-2E49-4B4E-AA17-FA0C853C248D.jpeg After about a year and a half, I’m going to try to finish this restoration. Life seemed to have gotten in the way. 

 


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#33 Gil V

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Posted 02 January 2022 - 07:42 PM

Yay

#34 Gil V

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Posted 03 January 2022 - 11:29 AM

Need any parts?

#35 photoracer18

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Posted 04 January 2022 - 04:24 PM

I don't think anyone on here with tons of Dynamax 8 experience would classify one as very good optics in the absolute sense. Check around especially with one or two that worked for Criterion in those days. I only own one and I bought it off CL knowing the issues because it was cheap and I wanted to play around with it.


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#36 Mitrovarr

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Posted 04 January 2022 - 06:49 PM

I don't think anyone on here with tons of Dynamax 8 experience would classify one as very good optics in the absolute sense. Check around especially with one or two that worked for Criterion in those days. I only own one and I bought it off CL knowing the issues because it was cheap and I wanted to play around with it.


Was the one you bought shipped? I need to get rid of mine at some point and I don't know what to do with it. I had assumed it would cost more to ship than it was worth and might not survive so I'm curious if someone else managed to make it work.

#37 Terra Nova

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Posted 04 January 2022 - 07:04 PM

If you have one and you have room, why not keep it? It is an interesting astronomy artifact, and IMO, the coolest looking of the American SCT Trifecta. You can always use is as a low power scope and a terrestrial spotter. 


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#38 RDFox

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Posted 04 January 2022 - 07:05 PM

Before and after media blasting.

 

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#39 RDFox

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Posted 04 January 2022 - 07:07 PM

Need any parts?

Yes I do. I need the knob that located on the base it rotates the scope.


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#40 Gil V

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Posted 05 January 2022 - 09:37 AM

RA Slow motion knob. I think I have one. I’ll have a look today.

One condition, though. You have to rebuild the scope. If, (as many here would suggest) you get rid of it, give it to a kid in the neighborhood that will get some use out of it.

The hate on this forum for the product line is unbearable to me personally. It’s not difficult to rehab the telescope, and a perfectly usable SCT can make a lot of folks happy.
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#41 Gil V

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Posted 05 January 2022 - 09:40 AM

Your mirror cell is showing signs of the hardware that secures the ears loosening (the visible vertical crack).

Since you have it broken down, I would consider drilling out the aluminum filler and replacing the hardware. If you scrap it in process, i do have a spare Dx8 mirror cell. Might be the same vintage.

Edited by Gil V, 05 January 2022 - 09:41 AM.


#42 Maximumron

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Posted 05 January 2022 - 01:47 PM

Your mirror cell is showing signs of the hardware that secures the ears loosening (the visible vertical crack).

Since you have it broken down, I would consider drilling out the aluminum filler and replacing the hardware. If you scrap it in process, i do have a spare Dx8 mirror cell. Might be the same vintage.

So to be sure, is the crack an actual joint that's opened up? And the hardware is the two round features, maybe socket cap screws embedded down in the ear? I have a Dx8 and would like to understand the construction better.

Thanks.



#43 RDFox

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Posted 05 January 2022 - 03:00 PM

I understand what you’re seeing. It’s still tight and snug, I seems to be a slight misalignment from the factory. Given what I’ve heard about these scopes I will gladly accept the detail and hope the optics are good. More pics coming.



#44 RDFox

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Posted 05 January 2022 - 03:08 PM

RA Slow motion knob. I think I have one. I’ll have a look today.

One condition, though. You have to rebuild the scope. If, (as many here would suggest) you get rid of it, give it to a kid in the neighborhood that will get some use out of it.

The hate on this forum for the product line is unbearable to me personally. It’s not difficult to rehab the telescope, and a perfectly usable SCT can make a lot of folks happy.

 

Yes, I never sell anything (I always find a good home for things) the fun is in the journey. My grandchildren will probably get this one. It will be easier to move around than my other one. Which I will never get rid of. 


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#45 RDFox

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Posted 05 January 2022 - 11:54 PM

So to be sure, is the crack an actual joint that's opened up? And the hardware is the two round features, maybe socket cap screws embedded down in the ear? I have a Dx8 and would like to understand the construction better.

Thanks.

 

The crack is just place where the two pieces are connected. They’re held together by a couple of threaded bolts that are counter sunk and have aluminum plugs filling the hole. You can see the other end of the small bolts from inside the cell. I didn’t see any logic in trying to separate them and taking a chance on damaging them.



#46 RDFox

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Posted 05 January 2022 - 11:57 PM

Ready for primer.

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#47 Gil V

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Posted 06 January 2022 - 11:16 AM

A couple things - as long as their is no play in the joint between the ears and the cell, you should be alright. Cracked paint at the joint is indicative of possible loosening of the (inaccessible) hardware.

Also, the tube, front cell and mirror cell were painted after bonding. We used black RTV to join the tube to the front and rear cells. We weighted the OTA with a counterweight on the rear cell to keep the assembly snug while the RTV cured, typically 24 hours.

 

The cell shown in the photo has properly secured ears. If yours are not, we should swap before you glue the tube up.

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Edited by Gil V, 06 January 2022 - 11:18 AM.


#48 Mitrovarr

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Posted 06 January 2022 - 11:25 AM

If you have one and you have room, why not keep it? It is an interesting astronomy artifact, and IMO, the coolest looking of the American SCT Trifecta. You can always use is as a low power scope and a terrestrial spotter.


I don't have room and I could use the space for astronomy equipment that actually functions.

#49 RDFox

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Posted 06 January 2022 - 01:31 PM

Terra Nova good idea! My house is turning into a museum which is my lifelong goal! Even if this doesn’t work very well, it’ll look really neat sitting along other astronomy stuff. Plus, I always have room for astronomy stuff, working or not.


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#50 RDFox

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Posted 06 January 2022 - 01:33 PM

A couple things - as long as their is no play in the joint between the ears and the cell, you should be alright. Cracked paint at the joint is indicative of possible loosening of the (inaccessible) hardware.

Also, the tube, front cell and mirror cell were painted after bonding. We used black RTV to join the tube to the front and rear cells. We weighted the OTA with a counterweight on the rear cell to keep the assembly snug while the RTV cured, typically 24 hours.

 

The cell shown in the photo has properly secured ears. If yours are not, we should swap before you glue the tube up.

You’re too kind! I think I’ll be ok, if not I’ll be saying %@!,¥§!!

Thanks




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