Telescope Plans, Hints On Scrounging, & The Perseid Meteor Shower
Rodger Morris (rodger@FISHNET.NET)
Thu, 31 Jul 1997 19:50:45 -0700
I mailed another 8 sets of telescope plans today (Thursday). This
brings the running total of sets of plans mailed out to 76. If anybody
else is interested in getting a set of these plans, please e-mail me
with your postal mailing address.
Mike Kendall of the Sidewalk Astronomers had this to say when I asked
him for suggestions about sources for primary lens blanks:
>you should mention portholes because you never know.......Someone
>somewhere someplace just might have a connection...they can also go to
>the local library and search for glass manufactures in business
>journals..They might find someone local that can get them a deal..
>Mike Kendall Sidewalk Astronomers
The Sidewalk Astronomers initially ground telescope mirrors from old
circular ship glass portholes. John Dobson reportedly made a buy of
about 4 tons of them for $1000 back about 25 to 30 years ago. However,
they are almost all gone, and portholes are _very_ hard to find out here
If you can find an old glass porthole, you might just have the makings
for a really good telescope for a really inexpensive price.
Another intriguing concept was advanced recently in the amateur
telescope makers archive. Reportedly, Willman-Bell sells kits consisting
of a tool and a mirror blank, but _BOTH_ pieces of glass are made of
Pyrex. If this is true, one should be able to buy one of W-B's kits, buy
a plate glass tool from another source, and essentially get two telescope
mirror blanks for the price of one.
I scrounged up some free material for the spider at my local airport. In
the past, I have helped the Experimental Aircraft Association with their
"Young Eagles" program. (BTW, look into this one for your Scouts, as it
is an _outstanding_ program, and has been endorsed in 'Scouting' magazine
by the BSA). They cut some .032" aircraft aluminum for me, some of which
I have used successfully for the 5" moon telescope Troop 808 made a few
weeks ago whilst we were at summer camp. For the 10" Night Stalker, I used
some 1/8" Plexiglas supplied by the Los Angeles Sidewalk Astronomers,
which also worked very well.
The cardboard tube for the eyepiece can be found for free in the produce
section of Hughes market. Find a holder for a roll plastic produce baggies
that is out of baggies. Voila! There is your 1 1/2" inner diameter tube.
As to the nails for holding together the baseplate, I opted for drywall
screws instead, reasoning that my telescopes would have a bunch of eager
Scouts and Cub Scouts jostling it, and that screws and glue might help to
hold it together better than nails and glue. Maybe not, but it sure won't
hurt, and it screws don't cost too much more than nails, if you buy them in
Troop 808 is planning to have a star party that is a bit out of the
ordinary. On the afternoon of Monday, 11 August 1997, we plan to get
together at the house of one of our Scouters who lives outside our city.
We'll put together a dutch oven multi-course dinner. While it is
simmering, we will do some rough mirror grinding on an 8" mirror for a
telescope that our Comet Patrol wants to build. After supper and after
it is dark, we'll use our 5" moon telescope (The Moon Shadow) and our 10"
general purpose telescope (The Night Stalker) to look at and sketch the
moon (satisfies one option for a requirement of astronomy merit badge).
Then we'll do some deep sky observation with the Night Stalker and a
pair of binoculars mounted on a tripod until the Perseid meteor shower
starts getting really spectacular. BTW, Jupiter will be within days of
being as close as it gets to the earth this year, and it is so bright in
the Night Stalker that it actually dazzles the eye when you look at it,
unless you use an eyepiece filter or put a circular piece of cardboard
in the tube with a 4" circular hole cut off-center. This essentially
converts the Night Stalker from a 10" telescope to a 4" telescope.
Finally, we'll whomp up a fruit cobbler, eat it whilst watching the
celestial fireworks, then lie back in our sleeping bags and watch the
light show until we fall asleep.
Another requirement for astronomy merit badge will be met by observing the
skies for at least 3 hours.
The Perseid meteor shower peaks that night at about midnight, and should
average about 75 events per hour as the meteors hit the earth's atmosphere
Then, I'll have to scramble fast to make it to work on Tuesday morning!
Boy, am I gonna be tired, or what?
Still in all, it oughta be fun!!!
Yours in Scouting,
Rodger Morris <email@example.com>
Asst. Scoutmaster, Troop 808 Wood Badge 416-18
Ventura County Council at Philmont, 1973
Camarillo, California, USA "I used to be a Beaver..."
Terry Howerton Sakima Group, Inc. SCOUTER Magazine Kansas City