Author Topic: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt  (Read 256 times)

byhodete

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #15 on: January 13, 2018, 08:53:59 AM »
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I made a pipe mount years ago for my 6 inch based on Sam Brown's design , it worked well but weighed a ton .

Have fun and look forward to seeing yours at Stellafane when you get it finished!

Norm

It won't be until the next convention, thanks, but hopefully my Dob will be this year.

How much does it weigh and how much does the mount cost?
I built it probably 35 years ago so I don't remember the particulars but it was HEAVY...didn't cost much as I was able to source scrap shafts and the stand (which was metal) from work for free. I gave it to a friend of mine who needed a mount and he has since passed away so not sure what happened to it since then . I took it over to Stellafane in 1980 for the convention with my 6 " scope.
Norm
As long as it weighs less than 40-50 lbs I'm pretty sure I can carry it.

Anton Balderrama

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #16 on: January 17, 2018, 12:14:42 AM »
You will really enjoy your long focus 6" on a pipe mount. I made my 6" f/10 when I was 13, and parabolized it. Truly a planet killer - Jupiter and Saturn were crisp and amazing. It took about 30 seconds of total polishing time to parabolize it from a sphere using washed rouge, and several hours to test it. My pipe mount followed Sam Brown's simple design using the threads as bearings - I wish I knew about Dave's design back then. But after lapping the threads with oil and 400 abrasive as recommended, the motions were very smooth and it was a joy to use. This mount weighed only about 20 pounds without the barbell counterweight and was easy to carry in and out, even for a scrawny nerd like me.
Solar observing with an eyepiece filter, seconds before the filter popped in half (no eye injuries, fortunately - DO NOT TRY THIS AT HOME!)

tessacubadc

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #17 on: January 18, 2018, 02:31:23 AM »
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You will really enjoy your long focus 6" on a pipe mount. I made my 6" f/10 when I was 13, and parabolized it. Truly a planet killer - Jupiter and Saturn were crisp and amazing. It took about 30 seconds of total polishing time to parabolize it from a sphere using washed rouge, and several hours to test it. My pipe mount followed Sam Brown's simple design using the threads as bearings - I wish I knew about Dave's design back then. But after lapping the threads with oil and 400 abrasive as recommended, the motions were very smooth and it was a joy to use. This mount weighed only about 20 pounds without the barbell counterweight and was easy to carry in and out, even for a scrawny nerd like me.

SolarObserving.jpg

Solar observing with an eyepiece filter, seconds before the filter popped in half (no eye injuries, fortunately - DO NOT TRY THIS AT HOME!)

So you still had a coated primary mirror? So you had a single filter blocking that much energy?

Chris Harwood

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #18 on: January 20, 2018, 07:20:25 PM »
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So you still had a coated primary mirror? So you had a single filter blocking that much energy?

It was freshly coated and as bright as could be. I'd seen Jupiter and the moon with it bare, but couldn't wait to get first light at something in the sky - anything - even the sun. But a sun filter makes it safe to view the sun, right? (WRONG) I got the sun into view and focused on it, and was enjoying the incredibly detailed granulation when I started seeing and smelling white smoke wafting out of the eyepiece holder base (it was my black flocking paper). Moments later it audibly popped and a "blinding" flash came through. Fortunately, with the naivety of youth also comes quick reactions. The filter element had a hairline fracture right down the middle, and the metal cell was slightly discolored. That's when I learned that a 6" f/10 is nothing to sneeze at.

getneyprotges

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #19 on: January 20, 2018, 11:14:52 PM »
UPDATE: Looks like my parents can't drive 4 hours each way once a month for the class, but I will be buying a 6" f/9 mirror soon.

Jose Melo

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #20 on: January 21, 2018, 02:02:29 AM »
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Sounds like a plan to me....two scopes are always better than one

And the best part is that I can go over to the refractor nuts and show them that my $600 Newt is better than their Takahashi....
Gee,

I thought I did already did this on paper (see below) and in reality with my Stellafane entry last year.

Attached Thumbnails


Coco Moten

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #21 on: January 21, 2018, 05:07:04 AM »
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Sounds like a plan to me....two scopes are always better than one

And the best part is that I can go over to the refractor nuts and show them that my $600 Newt is better than their Takahashi....
Gee,

I thought I did already did this on paper (see below) and in reality with my Stellafane entry last year.
If you can teach me how to make a scope that good I will be eternally grateful.

You'll have to show me that thing at the convention this year!

Jorge Herbert

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #22 on: January 21, 2018, 05:14:32 AM »
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You will really enjoy your long focus 6" on a pipe mount. I made my 6" f/10 when I was 13, and parabolized it. Truly a planet killer - Jupiter and Saturn were crisp and amazing. It took about 30 seconds of total polishing time to parabolize it from a sphere using washed rouge, and several hours to test it. My pipe mount followed Sam Brown's simple design using the threads as bearings - I wish I knew about Dave's design back then. But after lapping the threads with oil and 400 abrasive as recommended, the motions were very smooth and it was a joy to use. This mount weighed only about 20 pounds without the barbell counterweight and was easy to carry in and out, even for a scrawny nerd like me.

SolarObserving.jpg

Solar observing with an eyepiece filter, seconds before the filter popped in half (no eye injuries, fortunately - DO NOT TRY THIS AT HOME!)

Great idea, great scope size. Lapping the treads is a plus, makes it move really well. Mine is a 6" f/10.5  Enjoy.

Mohamed Wiest

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #23 on: January 25, 2018, 08:52:13 PM »
found picAttached Thumbnails


consurflola

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #24 on: January 29, 2018, 11:06:02 PM »
I made a telescope (6-inch, f/9, mirror ground, polished, and figured to be parabolic) based on Sam Brown's book in 1967. It utilized a 45-degree elbow, so I consider the mount to be "quasi-equatorial". The pipe was 3-inch black pipe throughout, cut and threaded at a local plumbing supplier, the Charles Hoffman Plumbing Supply of Mansfield, Ohio, if I recall correctly.

Mansfield is located at about latitude 41-degrees North.

I no longer own it. I donated it to the Richland Astronomical Society of Richland County, Ohio, which is based in Mansfield, Ohio. I suspect that it was immediately disassembled to harvest parts for other telescope-building projects.

The mount weighed about 40 pounds. I think that made for stability and helped to minimize vibrations.

This is my first post to Cloudy Nights. I hope that I uploaded the attached images properly.




Justin Prasad

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #25 on: February 08, 2018, 07:38:04 PM »
I finally found a picture that shows my 6 inch on my homemade GEM pipe mount. That was many moons ago, kids are grown up and have their own kids now
NormAttached Thumbnails


Leon Vale

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Re: Stellafane Mirror Making Class - 6" F/9 Equatorial Pipe Mount Newt
« Reply #26 on: February 09, 2018, 10:38:53 AM »
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So you still had a coated primary mirror? So you had a single filter blocking that much energy?

It was freshly coated and as bright as could be. I'd seen Jupiter and the moon with it bare, but couldn't wait to get first light at something in the sky - anything - even the sun. But a sun filter makes it safe to view the sun, right? (WRONG) I got the sun into view and focused on it, and was enjoying the incredibly detailed granulation when I started seeing and smelling white smoke wafting out of the eyepiece holder base (it was my black flocking paper). Moments later it audibly popped and a "blinding" flash came through. Fortunately, with the naivety of youth also comes quick reactions. The filter element had a hairline fracture right down the middle, and the metal cell was slightly discolored. That's when I learned that a 6" f/10 is nothing to sneeze at.

This is an interesting anecdote, SteveNH. I have one related to it since includes similarities.

First of all, I did something unsafe in perhaps 1965, when I was a 13-year-old, out of ignorance and insufficient caution, not the only unwise step that I took as a youth. I was fortunate. I suffered no ill effects. On the contrary, as did you, I enjoyed seeing "incredibly detailed granulation."

I had purchased a "solar filter" from Edmund Scientific through mail order. I wondered about the safety, but thought that since it was a productthat had been offered for some time, at least a year or two, it mustbe safe. If not, it would have been pulled from the catalog, or so I thought.

In any case, I used it with my 3-inch Edmund reflector, a rather poor telescope, but the best that I owned at the time. I inserted the solar filter before the eyepiece. Theview was quite fine, as noted above.I looked for only a few seconds.

I do recall that I was aware that the focusing tube might heat up because of the energy being absorbed within the filter and that I was curious to see if it would happen. I do not recall to what extent I checked for signs of heating. I suppose it is possible that the filter heated and rapidly reached an equilibrium state in which energy was being transferred to the environment by radiation, convection, and conduction. I believe that is a plausible explanation in this instance.

Since I was using a 3-inch, the amount of power to be dissipated was one-fourth of what it was when you were using a 6-inch.

I would never, ever repeat what I did then, nor should any other person.