It All Starts With The Mount
At some time or another, most amateur astronomers acquire through some
means or another a telescope that doesn't have a tripod. Or, in some cases,
a telescope with an inadequate tripod.
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If you've done much shopping for telescopes and accessories, you know by
now that a decent tripod costs a couple hundred dollars or more. That's kind
of a costly experiment, to buy a tripod for that money in the hope that it will
work.
This page describes a tripod that I built for a couple of my telescopes.
The total cost was only about $50 a few years ago. I get double duty with
this design, and if I happen to lay hands on another small scope to play with,
it'll be easy to add an attachment to carry that telescope as well.
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The Basic Tripod
Shown at left is the basic pipe fitting tripod design. It consists of a section of
2" pipe for the basic stand.
A 2" flange is mounted to a double-layer 3/4" plywood base.
Three 1" lengths of copper pipe extend from the center pipe to the
extremes of the triangular base. Copper was used because the ends could
be flattened for easy fastening to the center pipe and base.
An even more solid mount could be made by welding pipe legs onto the
center pipe, and letting them extend to the ground. This would eliminate
the plywood base.
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I choose this design at the time because I didn't have a welder in my
tool arsenal.
On top of the tripod is mounted a head designed to support a 2" refractor.
It would easily support a 60mm refractor.
By going to 2 1/2" or 3" pipe instead of 2", it could be sized up to handle
a larger telescope.
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The Tripod Feet
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The tripod feet are shown in this image.
First I mounted three 3/4" flanges to the underside of the plywood
base.
Then I simply screwed in three short (each the same length) nipples into
the flanges, and capped them to prevent them from digging into the ground.
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The result is a stand that is portable enough to be easily moved around
the yard, yet very sturdy.
In addition, about the only tools I needed was a pipe wrench or large
pliers, and a drill.
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The Tripod's Refractor Head
Shown is the head that can be mounted on the tripod to support the
2" refractor telescope.
It consists of a coupling that connects to the base, an extender to
accommodate the length of the telescope, and the bearing sections.
The azimuth bearing is formed by a 90 degree street elbow.
The street elbow screws into a flange that is mounted to a wooden bracket
that holds the telescope. This makes the elevation bearing.
To make the thread bearings work smoothly, I went to the local
auto parts store and purchased some valve grinding compound -- a kind
of gritty, greasy paste.
I put some of the compound on the azimuth threads, then screwed on the
street elbow. I tightened to hand tight the street elbow and backed it off
repeatedly. The grinding compound polished the threads of both the
extender pipe and the street elbow. After a few minutes, I gained a couple
of turns before the street elbow would be tight.
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I then removed the street elbow and cleaned the extender and street elbow
threads, applied a light coating of grease, and screwed the street elbow
back on. It now turns smooth as butter.
I did the same to the elevation bearing formed by the horizontal
section of the street elbow and the flange.
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The Tripod Supporting Refractor
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This image shows the tripod with the refractor head in place, supporting
the 2" refractor telescope.
It is, admittedly, an altazimuth mount, but one that is sturdy and has
smooth bearings.
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While not light as a feather, the unit is light enough that I can leave
the tripod and telescope assembled together, and still carry it out to set up,
or move around the yard.
That provides some pretty short setup time, and lets me squeeze in some
fun observing even if I only have 45 minutes or so for the entire session.
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The Cassegrain Wedge
This image shows a simple wedge I made to support my Meade ETX 90. I have
the older model that has a motor only on the right ascension axis, so to
get use from the clock drive the telescope must be in an equatorial
configuration.
The wedge is a simple triangle of wood cut to tip the telescope's polar
axis by my latitude angle. A bit more thought and I could have built an
adjustable wedge.
To the bottom of the wedge is mounted another 2" flange. The flange screws
to the telescope base, giving a solid yet portable mount for the Meade ETX 90.
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The Tripod Supporting Cassegrain
This is an image of the Cassegrain wedge mounted on the tripod base,
supporting the Meade ETX 90.
As you can see, the extender section of pipe isn't needed for the
Cassegrain telescope, so it has been removed.
I've found this to be a very solid mount for the ETX, and it would likely
support at least the ETX 105 as well.
Again, by scaling up the size of the pipe, a larger telescope could
be handled.
This is the mount that was used for the Meade ETX 90 when it was used
to make the moon images and planet images shown on the etx page.
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Personal Notes
If this gives you some slack, money wise, you might want to take another
look at some small Cassegrains, knowing that with simple tools and tens of
dollars you can make a fine tripod.
You could also take the risk on perhaps a 60mm refractor. The 60mm makes
a great first telescope, but often is shipped with a flimsy mount. This
mount would cheaply transform an optically decent 60mm into a fine performer.
Knowing that making an adequate tripod is straight forward and inexpensive,
you might want to take another look at some bargain telescopes at eBay
Stores  .
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