Amateur Telescope Makers' Resource List - 5/97 posting
Bob Lombardi
* * Amateur Telescope Maker's Resource List * *
An Internet Resource for over six years.
Last revised: May 4, 1997
Maintained by: Bob Lombardi, blom...@iu.net
Fellow sci.astro.amateur readers.
Here is the latest version of the ATM Resource List.
The best way to view this page is on my web site. The URL is:
http://www.freenet.tlh.fl.us/~blombard
It is echoed on
http://www.stellafane.com
The text version is available in the America Online and Compuserve Astronomy
areas, and is available via ftp from:
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If all else fails email me at either address in the signature file
below.
Removal of A. Jaegers' and E & W Optical - phones reported disconnected
Removal of the Astronomy Shoppe as a mirror producer
Edited Galaxy Optics to show minimum mirror size 18"
New phone number for Astronomische Materialzentrale SAM my one
European supplier.
New URLs for Crazy Ed Optical in Part V.
New URL for Newport Glass Works in part I.
New URL for Herbach and Rademan in part VII.
Corrected URL for Mark Vandewettering's ATM site.
Welcome to the ATM Resource List. My purpose is simple: despite
the widespread availability of cheap components and good optics, there
is a perception that getting the parts to build a telescope is harder
than ever. By putting together a list of companies that supply the ATM,
I hope to help make sure that Amateur Telescope Making does not die off
as a hobby, but instead grows into the future. It may be true that
big companies don't advertise mirror making kits in Popular Mechanics
like they did in the past, but the mirror making supplies are still
out there, and ATM-made mirrors are often the standard of comparison
for the best optics.
If you have any experience with these companies, new addresses or
phone numbers, or any other feedback, please email me to get your
updates included. Good, as well as bad, experiences are always
welcome. A particular weakness of this list is that it has a strong
North American, and especially US, bias. For about the last year,
Steve Tonkin of the UK has provided a list of suppliers over there.
Steve now has his own home page, which I provide the address of below.
As this list is at its best when seen by as many as possible, feel
free to archive it, post it on a WWW home page, or add it to a CD Rom
collection. Please do not modify it. If any modifications are needed,
contact me to ensure that everyone sees the latest corrections.
I must issue the std disclaimer: I have nothing to do with any of
these companies, other than being a satisfied customer of a few, and
an ex-customer of some others.
The list is not complete, but does cover the most needed things. Here
goes.
* * * * * * * * * *
Other Cool ATM Sites
Mel Bartels Computerized Dobsonian site
http://zebu.uoregon.edu/~mbartels/altaz/altaz.html
Matt Marulla's ATM Page
http://www.tiac.net/users/atm/
Stellafane
http://www.stellafane.com/
Tallahassee Astronomical Society
http://www.polaris.net/~tas/tas.html
Mark Vandewettering's Home Planet
http://www.idle.com/~markv
* * * * * * * * * *
Amateur Telescope Maker's Resource List
Part One: North American Sources
I. Mirror Making Kits and Supplies:
The following companies sell telescope making supplies, including
mirror blanks, lens blanks, abrasives, polishing agents, and other
helpful accesories.
US
Glass Fab Inc., 257 Ormond St, Rochester, NY 14605,
(716) 262-4000. Blanks, including Sitall
Newport Glass Works, Ltd., 2044-D Placienta Ave., Costa Mesa
CA, 92627 phone 714-642-9980 Supplies pyrex blanks,
tapered (SCT) blanks, lens blanks, colored filter blanks,
plus abrasives and pitches. http://www.newportglass.com/
Salem Distributing Company, Inc. Box 25566 Manor Station,
Winston-Salem, NC 27114, 800-234-1982 Contact: Randy Reins
Originally the source of the opthalmic polishing pads
discussed in S&T's ATM column, they now sell a complete
line of grits and polishing agents. Very friendly.
These folks sell primarily to the eyeglass industry.
United Lens Co., Inc., Southbridge, Mass. 01550 508-765-5421
United is a major producer of optical glass for industry.
They have been reported as a source of pre-rough shaped
blanks in unit quantities, and refractor objective blanks.
Willmann-Bell, Inc. P.O. Box 35025, Richmond, VA 23235
phone 804-320-7016 catalog $1 Consistently good
recommendations on the net. Pyrex blank/pyrex tool kits,
ceramic tiles for tools, plus a complete line of pitch and
abrasives.
Canada
Eftonscience Inc., 3350 Dufferin St., Toronto, Ont. M6a 3A4
ph 416-787-4581 catalog $6
II. Mirror Coating Services
US
Evaporated Metal Films,239 Cherry Street, Ithaca, NY 14850.
Phone 800-456-7070; Fax 800-456-3227. For customer service
dial ext. 47, Annja Aho or ext 25, Dave Cottrell. In addition
to Protected Al and Enhanced Al, they offer a wide variety of
antireflection, beamsplitter and filter coatings. They have
been in the thin film coating business for 60 years, and are
generally well respected in the ATM community.
P.A.Clausing, Inc. 8038 N. Monticello Ave. Skokie, IL, 60076
708-676-0330 Voice, 708-676-2930 Fax, e-mail:
hcl...@interaccess.com, Beral, Silver, Gold, Aluminum,
Copper, Rhodium, (most other evaporable metals) and
Overcoatings, Fast turnaround available. Can do up to
90" diameter, up to 1 ton weight (3 tons next year).
Precision Applied Products, 418 Rumsey Place, Placentia, CA 92670
714-738-4775 In addition to standard and enhanced mirror
coatings, they offer MgF2 for refractor lenses and windows.
QSP Optical Technology. 1712-J Newport Circle, Santa Ana, CA
92705 (714)-557-2299 Fax: 714-557-2170 Standard, enhanced
and Anti-Reflective coatings. Can handle up to 64" diameter
optics. 7 working day turnaround.
Southwest Optical Technologies, PO Box 65867, Tucson, AZ 85728
(520)-881-0863. Vacuum coatings by Lynn Hepburn.
Canada
Moonward Vacuum Coatings, Suite 250, 800 Lasalle Blvd., >Sudbury,
Ont. P3A 4V4 Phone: Alan Ward (705) 566-7924
FAX: (705) 566-1833 E_mail: moon...@osiris.isys.ca Four levels
of aluminum: bare aluminum; protected (coated with SiO);
semi-enhanced (coated with MgF2) and enhanced (MgF2/Zns).
Up to 16". Turn around time is 1-2 weeks for the first three,
2-3 for the Enhanced. Secondaries are done free if sent with
the primary.
III. Telescope Making Books and publications
Periodicals
_ATM Journal_. The Amateur Telescope Makers Association
(ATMA) 17606 28th Ave. S.E., Bothell, WA 98012. This has the
"look and feel" of the old _TM_. Membership is $20. Visit their
website at http://www.halcyon.com/rupe/atmj/ or email
Bill Cook, the editor, at at...@aol.com.
_AMATEUR ASTRONOMY_. 2111 Whitield Park Ave, Sarasota, FL 34243
(941)-758-9890 Edited and published by Tom Clark and Tectron.
Now in its second year. Coverage of Amateur Astronomy events,
issues, people, and telescope making.
_Astronomy_ occasional material for TM's. Check your bookstore
or newstand Visit their website at:
http://www.kalmbach.com/astro/astronomy.html
_Sky and Telescope_ monthly column for TM's. Again, check your
newstand, or mall bookstore Visit their website at:
http://www.skypub.com
Books
Beginner
"Build Your Own Telescope", Richard Berry, Pub by Kalmbach
Publishing (pub. of Astronomy) ISBN 0-684-18476-1
$24.95 + $1.50 s&h. Now in the Willmann-Bell catalog.
http://www.willbell.com/
"How to Make a Telescope", Jean Texereau, 2nd ed., Pub and
sold by Willmann-Bell, ISBN 0-943396-04-2, $19.95 +$1 s&h,
address above (under tm supplies) http://www.willbell.com/
"Making and Enjoying Telescopes", Robert Miller and Kenneth
Wilson, Sterling Publishing, 1995, ISBN 0-8069-1277-4,
$24.95 at bookstores. 6 telescope projects using commercial
optics, superb photos and illustrations. Written for absolute
beginners.
"Making Your Own Telescope", Allyn Thompson, Sky Publishing,
1947, 1973, ISBN 0-933346-12-3, $ 14.95 + s&h from
Willmann-Bell (also available from Sky Publishing). Dated,
but lots of solid info and advice. Concentrates on a 6" f/8.
Advanced
"A Guide to Building Truss Tube Telescopes", Randy Cunningham,
AstroSystems. (no ISBN) "Basically the instruction/ guide book
for building a Truss Tube Telescope with the components that
come with our current kits". $19.00 + Shipping. AstroSystems,
Inc., 5348 Ocotillo Ct., Johnstown, CO 80534 303-587-5838,
http://www.frii.com/~astrosys
"Advanced Telescope Making Techniques", Volumes 1 and 2, ISBN
0-943396-11-5 (vol 1) and 0-943396-12-3 (vol 2), pub by
Willmann-Bell, address above, http://www.willbell.com/
"Amateur Telescope Making, books 1, 2, & 3", Albert Ingalls, editor.
Perry Remaklus, editor of the new series. ISBN 0-943396-48-4 (v.1),
0-943396-49-2 (v.2), 0-943396-50-6 (v.3) Published by Willmann-Bell.
http://www.willbell.com/
Probably the most important event in the ATM publishing world in
a decade, this is a reprint of the classic series originally
published by Scientific American starting in the 1930s and used by
ATMs ever since. NOTE: This set has been re-compiled by the new
editors at Willmann-Bell so that it is not a 1 for 1 replacement
for the originals. The material has been re-grouped so that
sections on a given topic that may have been spread across all
three volumes by time sequence now appear in a coherent section.
If you have one or two of the originals and are planning on using
this new series to complete your set, be advised that you can't
just buy the missing volume. But it's still worth it, IMO.
"Telescope Optics: Evaluation and Design", Rutten and
van Venrooij, ISBN 0-943396-18-2, Willmann-Bell, companion
software available, http://www.willbell.com/
"Microcomputer Control of Telescopes", Trueblood and Genet
ISBN 0-943396-05-0, Willmann-Bell, http://www.willbell.com/
"Prism and Lens Making" F Twyman, ISBN 0-85274-150-2, pub by
Adam Hilger, NY, 1988 (corrected reprint)
"Astronomical Optics" Daniel J. Schroeder, Academic Press,
1987 ISBN 0-12-629805-X, Advanced undergraduate text with
loads of info. Sold by Willmann-Bell, http://www.willbell.com/
Other
Videos:
* "How to Make a Telescope", John Dobson, 2hr Video
Dobson Video, PO Box 460915, San Francisco, CA 94146-0915
Make check to "Dobson Astro-Initiatives" Cost: $43 (includes postage
and handling) (Calif residents add $3.40 sales tax) From the ad,
"For the first time on video, John Dobson shows how you can build
your own high-power, low-cost telescope. The 2 hour video is a
complete step-by-step guide, covering telescopes 8" to 16" and
larger."
* "Collimation of Newtonian Telescopes" by Rich Combs and Alan Gorski
Richard Combs, 5151 Greentree Ct., Pleasanton, CA 94566, Cost: $20,
shipping included in the US. A limited quantity of the tapes is also
available from LUMICON.
A 37 minute step by step guide to collimation principles and
techniques. Targeted primarily at the Newtonian type reflector.
Extensive description and use of collimation tools. Tips, tricks, and
many special mock-ups intended to aid understanding and help improve
your telescope's performance.
Internet Resources:
The ATM internet mailing list is a valuable source of Telescope Making
Information. You can subscribe by sending mail to majordomo.shore.net
with the message "subscribe atm" in the body. Don't use a subject,
and don't add anything else to the note. This is an automated
server, and no human will touch your request.
If you want to see the archives of the last year or so, go to
http://www.system.missouri.edu/ics/staff/andy/ATM/atmarchive.html
This is The ATM Archive, maintained by an...@www.system.missouri.edu
IV. Commercially-Made Optics
US
Clear Star Optics, 4193 Tallmadge Road, Rootstown, OH 44272
(216-325-1722) Newtonian Mirrors, also flats.
D & G Optical, 6490 Lemon Street, East Petersburg, PA 17520
717-560-1519 Refractor objectives, apochromatic (5.1") and
achromats (5 -12") Refractor Tube Assemblies (OTAs) 5" to 12"
Classical Cassegrain sets and OTAs. Also parabolic mirrors
through 20". Refigures finished mirrors.
Edmund Scientific, dept 10B1, N919 Edscorp Bldg, Barington,
NJ 08007 http://www.edsci.com Edmund is not the astro company
they once were, but they do carry a lot of lenses and some
other optical components.
Enterprise Optics, P.O. Box 413, Placienta, CA 92670
714-524-7520 Newtonian and Cassegrain Optics, 6" to 24"
Elliptical flats to 6".
Great Plains Instruments, David Harbour, 610 N 14th, Enid, OK 73701
(No phone). Mirror grinding and finishing (no coating),
mirror refiguring, testing and evaluation. Contact by mail only.
Galaxy Optics, P.O. Box 2045, Buena Vista, CO 81211
719-395-8242 A very well respected name in finished mirrors.
Produces only mirrors of 18" and over.
Iowa Scientific Optical, 4231 Northwest Drive, Des Moines, IA 50310
(515-255-0166) Newtonian and Schiefspigler Optical sets, flats,
mounts, tube assemblies and complete telescopes.
J.C. Wilkinson Optics 303-499-7662 (Boulder, Colorado)
Jerry Wilkinson, senior optician for seven years for Galaxy
Optics. Primarily refiguring services, but will also quote
finished mirrors. He will figure mirrors from 6" to 14.5".
JSL Perpetual Technology, Inc., 275 East 100 North, P. O. Box 51
Willard UT 84340, (801) 723-5568, Primary mirrors 6-30",
focusers, eyepieces and mounts.
Lumicon, 2111 Research Dr., Suite 5, Livermore,CA 94550
510-447-9570 Filters, UHC, H beta, O-III, Swan, and more
Full line supplier of astronomy and astrophotography supplies
http://www.rahul.net/resource/regular/products/lumicon/
NOVA Optical Systems, P.O. Box 80062, Cornish, UT 84308,
(801) 258-5699. 10 to 25" Newtonian Mirrors, f4-f10.
Orion Telescope Center, 2450 17th Avenue, PO Box 1158
Santa Cruz, CA 95061 800-447-1001, http://www.oriontel.com
Newtonian primaries, 6 - 12.5", & secondaries. They have several
email addresses: sa...@oriontel.com" for Sales/Product Info
ste...@oriontel.com for the New Product department and
sup...@oriontel.com for Customer Support
Parks Telescope Co., c/o Scope City, 679 Easy Street, Simi Valley,
CA 93065 (805) 522-6646, Newtonian primary mirrors 4.5-16",
secondaries. These are the mirrors used in Parks' telescopes.
Pegasus Optics RR 5, Box 502, Huntsville, AR 72740,
Phone: (501) 738-1650 9am-9pm 16 to 28" Mirrors, Lifetime
warranty, test/certs for all mirrors sold.
Precision Applied Products, 418 Rumsey Place, Placentia, CA 92670
(714)-738-4775 or 800-575-4775 Refractor lenses, 5" to 12"
(this is the same company listed in coatings, above).
Star Instruments, PO Box 597, Flagstaff, AZ 86002
520-774-9177, 10" TO 40" Newtonian, Classical Cassegrain
and Richey-Chretien Cassegrain optics. Catalog $2 US/$3 others
Steve Swayze Optical, 700 NE 101st Ave., #31, Portland, OR 97220,
Phone: (503) 252-5009, Fax: (503) 335-3320
http://www.europa.com/~swayze/ or swa...@europa.com
Custom mirrors in 12.5" to 30".
United Lens Co., Inc., Southbridge, Mass. 01550 508-765-5421
University Optics, P.O.Box 1205, Ann Arbor, MI 48106
800-521-2828, sells a small line of mirrors in addition to
the other supplies listed in part 5.
Canada
Arnold Optics (Barry Arnold) 433 Sioux Road, Sherwood Park,
Alberta, Canada T8A 4H2 Phone/Fax:(403) 467-4781.
Newtonian paraboloid and secondary mirror optic sets: 8" to 16",
larger on special order. Optical windows, achromatic refractor
lenses (to order), mirror diagonals, prism diagonals,
Optical design consulting, & custom optical element fabrication.
Paraboloid and flat evaluation and refiguring.
Telstar, 2130 Primate Rd, Mississauga, Ontario ph 905-270-8744
http://www.interlog.com/~dbig/telstar/ or...telstar@interlog.com
Primarily sell their own Cassegrains, but willing to quote custom
mirrors.
V. Telescope Parts (finders, focusers, eyepieces, etc., etc.)
Apogee Inc., P.O. Box 136, Union, IL, 60180-0136, 815-923-1602
email: AstroS...@il-icom.net, or visit
http://www.rahul.net/resource/regular/products/apogee/
Optical and astronomical surplus including fiberglass telescope
tubes, eyepieces, motors, finder scopes, and some optics.
The Astronomy Shoppe, 15836 N. Cave Creek Rd, Phoenix,
AZ (602)-971-3170. Custom mirrors and "Bigfoot" mounts.
AstroSystems, Inc., 5348 Ocotillo Ct., Johnstown, CO 80534
303-587-5838, http://www.frii.com/~astrosys
Primarily parts for big Dobsonians. Truss tubes, mirror
cells, formica, secondaries, focusers, huge elevation
bearings (like on the Obsession scopes), and more. Produces
telescope kits.
Ceravolo Optical Systems, Peter Ceravolo, Box 1427, Ogdensburg,
NY 13669 (613) 258-4480 Supplies for Interferometry,
testing for ATM's, instruction booklets, interferometer
parts and analysis software.
Crazy Ed Optical, P.O. Box 110566, Campbell, CA 95011-0566
Phone or Fax: (408) 364-0944. E...@crazyedoptical.com
http://www.crazyedoptical.com Dobsonian parts: Ebony
Star formica, teflon, tube trim. Spiders, diagonal holders
and mirrors, focusers, finders (Telrad and Conventional),
LED lamps and flashlights, charts, and even more.
Edmund Scientific, address above
Equatorial Platforms, 11065 Peaceful Valley, Rd., Nevada
City, CA 95959 catalog $2 Poncet platforms.
http://www.rahul.net/resource/regular/products/eq_platforms
Hollywood General Machining (Scott Losmandy) Hollywood, Ca.
213-462-2855. Losmandy mounts are sold by Celestron and
other big companies. He reportedly sells direct as well.
Kenneth Novak & Co., Box 69T, Ladysmith, WI 54848
715-532-5102 Generally regarded as one of, if not _the_,
best makers of cells, spiders, and other mechanical parts.
Jim's Mobile Inc., 810 Quail St. Unit E., Lakewood, CO 80215
Orders 800-247-0304, info 303-233-5353, Better known as JMI,
the makers of the NGT-18 telescope. They carry one of the
largest lines of focusers on the market, including motorfocusers.
All JMI focusers are Crayford type, often considered the best.
They also carry NGC Max computers.
Lumicon, address above
Malco Precision Products, 138 B Lamar St., West Babylon, NY 11704,
1-800 895-1298, or 516-253-0720, Fax 516-491-5519
email: Ma...@ix.netcom.com Parts for Truss style Dobsonians
designed for quick assembly and disassembly. Brackets for the
bottom box and top cage to accept aluminum poles. One size of
aluminum poles (you cut to final length). All parts are Stainless
Steel or Black Anodized Al., except the upper clamps whice are
Galvanized Steel.
Motion Control Systems, P.O. Box 19632, Portland, OR 97280,
503-244-0503, Telescope Mounts and accessories, catalog $2
Opti-Craft Machining, 33918 Macomb, Farmington, MI, 48335, (810)-
476-5893. "Quality clock drives and telescope accessories",
according to the catalog. Highly precise gears, worm drives.
Orion Telescope Center, 2450 17th Avenue, PO Box 1158
Santa Cruz, CA 95061 800-447-1001, Orion has gradually become
a complete supplier for ATMs: spiders, diagonals, focusers,
mirror cells, finders, filters, eyepieces, barlows, etc..
One of America's largest dealers. They have several email addresses:
sa...@oriontel.com" for Sales/Product Info ste...@oriontel.com
for the New Product department and sup...@oriontel.com for
Customer Support. Also http://www.oriontel.com
Parks Telescope Co., c/o Scope City, 679 Easy Street, Simi Valley,
CA 93065 (805) 522-6646, markets parts used in their telescopes;
miror cells, spiders, focusers, mounts, clock drives &
correctors, eyepieces, etc.
Photon Instument, Ltd. 122 E. Main St, Mesa, AZ 85201 (602)-835-1767 or
(800)-574-2589. Restorations, optical testing, unobstructed
reflectors, as well as custom telescope manufacturing
ProtoStar Astronomy Products, P.O. Box 258, 108 E. Granville Road, Bldg. C,
Worthington, Ohio 43085, (614)-785-0245, new fax: (614)-785-0401
Professional quality diagonal holders and spider assemblies (among
other things) http://www.fpi-protostar.com/ or email to f...@ds.net
SOFT-TEC Systems, 9333 Crowley Rd., Suite A, Fort Worth, TX 76134-5904
(800) 354-1256 / (817) 293-8446 / fax (817)293-8606 sells
"SKY PROBE 1000" Telescope Positioning System, SW for PC. motor
driver electronics and cables, hand control, stepper motors
Stardrive Systems, 233 Bannock St., Denver, CO 303-722-4104
Mirror cells, 4-1/4 to 20"
TL Systems, 2184 Primrose Ave., Vista, CA 92084, ph/fax-619-599-4219
Equatorial platform and binocular viewer kits. email:
tlsy...@ix.netcom.com, http://www.nbn.com/people/sunspot/
tlsystems
Tech2000, 3349 SR99 S, Monroeville OH 444847, (419) 465-2997
Dob Driver II computerized drive systems for commercial
or homemade Dobsonians.
Tectron Telescopes, 211 Whitfield Park Avenue, Sarasota,
FL 34243 (941) 758-9890 Parts as well as complete instruments
Televue, 100 Route 59, Suffern, NY 10901 (914) 357-9522
http://www.rahul.net/resource/regular/products/tele-vue-optics/
Some of the finest eyepieces made, plus other items.
University Optics, P.O.Box 1205, Ann Arbor, MI 48106
800-521-2828, Focusers, finders, mirror cells, CCD camera kits
for the Cookbook Camera, telescope tubes.
Canada
Arnold Optics (Barry Arnold) 433 Sioux Road, Sherwood Park,
Alberta, Canada T8A 4H2 Phone/Fax:(403) 467-4781.
Newtonian primary cells, custom-built with larger optic sets.
Machine shop services for optical parts. Small parts
aluminum anodizing. Direct vision prism type spectroscope.
Maestronix, 2025 rue Lavoisier, local 195, Ste-Foy, QC, G1N 4L6,
phone: 418-681-6567 fax: 418-681-6250 Eureka 2001 telescope
positioning system, hand control operated with computer interface
and software. Database of objects to observe and observation
software. http://www.maestronix.com/eng/eureka.htm or
email pdu...@maestronix.com
Telstar, 2130 Primate Rd, Mississauga, Ontario ph 905-270-8744
http://www.interlog.com/~dbig/telstar/ or...telstar@interlog.com
Scope to PC encoder systems.
VI. Miscellaneous
In the past couple of years, the role of electronics, and especially
stepper motors, has increased dramatically. The modern ATM is often
a computer user who controls the telescope with a computer, or other
electronic drive system. To that end, the ATM Resource List has been
expanded to include more electronics dealers. Stepper motors are often
available cheap or free from various sources. There are many excellent
web resources for those new to using stepper motors; among the best is
called Jones on Stepper Motors, and found on the web at
http://www.cs.uiowa.edu/~jones/step/index.html
Alltronics, San Jose, California (408) 943-9773
http://www.alltronics.com Alltronics is an industrial surplus
electronic dealer. Good source for stepper motors and drive
electronics. (A recent catalog had ten stepper motors, and
an assortment of ten for $16.95). HeNe laser tubes, power
supplies, vacuum tubes, logic and linear integrated circuits.
Minimum order $15.
American Science & Surplus, 3605 W. Howard St., Skokie, IL 60076.
Web site URL is http://www.sciplus.com (Formerly American
Surplus, Inc., Jerryco.) Has carried copier lenses for finder
scopes, heat ropes for dew-removal, and lots of weird stuff.
Automatic Tubing Corp. Brooklyn, NY 11222 USA, 718-383-0100; Out Of
State Call Toll Free: 800-527-3091 FAX: 718-349-2518 Large
Inventory For Emergency Or J.I.T. Shipping. Brass and other
tubing.
Digi-Key, Toll free: 800-DigiKey (800-344-4539)
http://www.digikey.com Digi-Key is an electronics components
retailer. Free catalog. They do not have a minimum order amount,
but add a $5 handling fee on orders for less than $25. No
additional charge for normal shipping (delivery within a week).
(Note that the WWW address does not have the hyphen!)
Hastings Irrigation Pipe Co., P.O. Box 728, Hastings, NE 68902
(402)463-6633 Supplier of aluminum irrigation tubing . One
reader "obtained some that's .064" wall thickness and comes
in 12, 10, 8, 7, 6, 5, 4, 3" diameters. The tubing is pretty
cheap (the 6" by 4' was $12.24 + shipping (8/94)) and the
company ships COD". Minimum order $50. (11/96).
Herbach and Rademan (800) 848-8001. http://www.herbach.com
Industrial surplus. Electronics, stepper motors, power supplies.
AC and DC motors. No minimum order, but $5 handling for small
orders (under $25). Free catalog.
Marlin P. Jones and Associates (516) 848-8236. http://www.mpja.com
Another electronics-oriented surplus dealer. Power supplies,
optics, and stepper motors have been in their catalog. Minimum
order $15.
Mouser Electronics (800) 346-6873 http://www.mouser.com Yet another
industrial distributor of electronic parts. Free catalog. $5
handling fee on orders for less than $20.
Newark Electronics Various offices, check locally or call Chicago
headquarters (312) 784-5100. One of the largest industrial
distributors of electrical parts. Big catalog. Minimum order
of $25 for prepaid order (check with order).
Public Missiles Limited, 38300 Long, Harrison Twp., MI 48045
(810) 468-1748</em> Like Hastings Irrigation, these folks probably
won't know what you're doing with their products. They sell high-
power rocketry kits and construction supplies, including phenolic
tubes. For those of you making 4 to 10" scopes, these tubes may
be useful.
Small Parts, Inc. 13980 N.W. 58 Ct. P.O. Box 4650, Miami Lakes, FL
33014-0650 305-557-8222, Small gears, tubes, nylon, teflon,
screws, setscrews, taps, tools and enough other small mechanical
parts to glaze over the eyes of any model builder. If you
can't find it here, it doesn't exist!
Part Two - Europe
The UK ATM Resources have moved to their own web page. The URL is
http://www.aegis1.demon.co.uk/atm.htm. If you don't have web access, you
can email the list coordinator, Steve Tonkin at s...@aegis1.demon.co.uk.
Europe
Astronomische Materialzentrale SAM, Postfach 715,
CH-8212 Neuhausen a/Rhf., Switzerland, 41 (0) 52 672 3869
(where the 0 is only dialed internal to Switzerland, 41 is
the country code). Complete mirror kits. Also sells finished
mirrors, eyepieces, focusers. Catalog approx $2. The catalog
is in German, but phone personnel apparently speak English and
other languages.
Summary and Advice for the Beginner
As a telescope maker, I often get asked the question, "should I build or
buy my telescope?". My favorite answer is "Yes!"; here's what I mean. If
you're new to amateur astronomy, count me as one of those who recommends
getting a nice pair of binoculars 7x50 or 8x56 as your first instrument.
Higher magnification (the first number) makes the binoculars harder to hand
hold so I'd recommend you stay clear of the 10x50 binoculars that you'll find.
Larger numbers in the second place mean the objective lens is bigger, which
is what you want for astronomical use. In general, 35mm binoculars such as
the common 7x35s are considered the smallest ones worth getting for astronomy.
Avoid bird watchers sizes (usually 15 or 20 mm). Get good ones (it's hard
to go wrong with binoculars made by the big optical companies) so that if
you decide that going to faraway dark places and staying up all night isn't
as much fun as it first seemed, you'll have a nice pair of binoculars that
you can use for life. If you're committed to astronomy, buying a reasonable
telescope can keep you occupied while you take on the long task of building
one. Nothing can be more frustrating than missing a beautiful night
(especially if they're as rare where you are as they are here) because the
telescope isn't working, yet. You can find used Celestron and Meade 'scopes
pretty much anywhere, and one of those might keep you going while you build
that 17" Dob that you've been dreaming of.
If you're considering doing your own optics, get the Willmann-Bell catalog.
It's a small newspaper filled with interesting books, and they sell mirror
making supplies.
Get Richard Berry's book "Build Your Own Telescope". Check out the
chapters on homebrew optics. If you can't find an experienced tele-
scope maker to help you, start small. It will take you less time to
grind and polish a 6" f7 or f8 mirror and then do your fantasy 12"
(or 17, or whatever) than to start with the big one. Even if you
finish your 6" scope and then never use it. If you have someone to
turn to for help, an 8" f7 or 8 makes a good starter scope. If you're
going to work on your own, get Texereau's book. Between the two of
them you can figure out what is going on.
Use a template to judge your rough curve. Cardboard is ok, you'll
learn where the uneven spots are in its shape.
As you progress through the grinding stages, spend more time with
the tool on top. In the finest grades the tool is almost always on
top. Say one wet with mirror on top to 10 with tool on top. This
concentrates the work on the edge, where you need it most. The
outermost edge contains most of your mirror's area, the innermost
circle is covered by the diagonal. (source for this idea, TM#6)
I like mats for molding the pitch lap. John Dobson uses a thin
wooden dowel pressed into the hot pitch. One of the most common flaws
in a first mirror is inadequate polish. Either of these techniques
will help you get a better lap. In addition, you should micro-facet
your lap with fiberglass screen (I got mine at the local building
supply house). It can save you an hour on even a 6 inch mirror.
The opthalmic polishing pads that have been mentioned in S&T and
other places polish extremely fast. I would recommend them only for
someone who has already polished out a mirror on pitch. On the
other hand, I wouldn't dream of doing a mirror over 10" without them.
You will need to monitor the surface with frequent Ronchi tests (just
as they polish fast, they can also turn an edge extremely fast) and
then follow the pads with a half hour to an hour on pitch.
You should test your mirror more than one way. The Ronchi test, using
a grating of 85-100 lines/inch, is excellent for checking the surface
during polishing to ensure you're not turning down your edge. It's also
bright enough to do in normal room light, unlike the Foucault test. The
star test can be a very sensitive way to determine the overall figure of
your mirror, but requires a tube and all of your other components to test
with. It may be even more important than the Foucault test, but do the
Foucault or similar test anyway; it's the most accessible way to get
the overall correction in waves that you want.
If you plan to buy commercial optics, learn to test a mirror anyway.
You can use the star test or a Foucault tester. University Optics
sells a nice kit, if you don't want to make one. One of the advantages
of grinding your own mirror is that you build a tester and learn to use
it as part of the process. Of course, you also have control of when
it's "good enough", and are not under the production pressures that a
commercial mirror maker is. Commercial mirrors vary in quality quite
a bit, and even the best companies will occasionally let one slip by.
So make sure you test your mirror and make sure you understand the test.
Don't expect an f4 Dobsonian mirror to be optical perfection; it is quite
difficult to achieve diffraction limited performance from an f ratio this
short. Of course if you're _paying_ for diffraction limited, that's
something else!
There you have it. Enough references to get the beginner started.
If you find this list useful, or if you find it lacking, I'd appreciate
feedback.
Clear skies...
Bob
All material Copyright 1997 Bob Lombardi, with editing help from Fourier,
the cat.