dobsonian manualv2

8/8/2019 DOBSONIAN manualv2

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This manual was created using Acrobat 4.0 you need to download the lat
http://www.adobe.com/products/acrobat/readermain.html


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E-mail:

Ray Cash-Le Pennec

To my other WebPages:

My Vanity Page

My Deep-Sky Page

How to Build a 13"HoLTravel Scopy Page My ash-Le
http://www.raycash.us/perso/index.htmhttp://www.raycash.us/deepsky/deepsky.htmhttp://www.griffithobs.org/StarAward.htmlhttp://www.starastronomy.org/TelescopeMaking/WebRing/index.htmlhttp://www.webring.org/cgi-bin/webring?ring=TelescopeMaking;id=97;next5http://www.webring.org/cgi-bin/webring?ring=TelescopeMaking;id=97;nexthttp://www.webring.org/cgi-bin/webring?ring=TelescopeMaking;listhttp://www.webring.org/cgi-bin/webring?ring=TelescopeMaking;randomhttp://www.webring.org/cgi-bin/webring?ring=TelescopeMaking;id=97;prevhttp://www.webring.org/cgi-bin/webring?ring=TelescopeMaking;id=97;prev5http://www.starastronomy.org/TelescopeMaking/WebRing/index.htmlhttp://www.raycash.us/scopeandimaging/1stccds.htmhttp://www.raycash.us/perso/sidewalk.htmhttp://www.raycash.us/deepsky/deepsky.htmhttp://www.raycash.us/perso/index.htmhttp://www.raycash.us/sfsidewalk/faqs2.htmhttp://www.raycash.us/sfsidewalk/upskirt.htm


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Plans for Building a Dobsonian Telescopebrought to you by: The San Francisco Sidewalk Astronomers

es, it "looks liket to 10 rg/F1ec5a3iove is 0 ally/F1ten-inch (measuredrgec5adia612er of ec52.99
http://www.raycash.us/perso/sidewalk.htmhttp://209.66.79.40/orion/dir2.icl?SECID=5&SUBSECID=13&ORDERIDENTIFIER=ID896658307218420243B04818http://209.66.79.40/orion/dir2.icl?SECID=5&SUBSECID=13&ORDERIDENTIFIER=ID896658307218420243B04818http://users.uniserve.com/~victorp/http://tie.jpl.nasa.gov/tie/dobson/index.htmlhttp://www.raycash.us/perso/sidewalk.htm


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http://www.raycash.us/sfsidewalk/sources.htm


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Some not-too-technical advice before you begin...
http://www.oriontel.com/http://murni.com/coulter.htmhttp://209.66.79.40/orion/dir2.icl?SECID=5&SUBSECID=13&ORDERIDENTIFIER=ID896658307218420243B04818http://users.uniserve.com/~victorp/


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or telescopes with mirror diameters 16" and larger, a different tube box design and mirror support

stem is necessary. (Again, John Dobson's telescope-making videolisted in "Sources" shows the

nstruction of a 16" telescope with this modified tube box and support ssu. Amodre popuarg ,yaMs
http://www.raycash.us/perso/index.htm


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= C L L G TH =L G TH T U r i rr r l r i l w r r ri l i l r rw !T i r i l r

Thekey thing to rememberis thatyou


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http://www.crazyedoptical.com/http://www.crazyedoptical.com/


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http://www.oriontel.com/http://murni.com/coulter.htm


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http://www.freenet.tlh.fl.us/~blombard/http://www.crazyedoptical.com/http://www.astromart.com/


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Newport Glass Works, LTD; 2044-D Placienta Ave; Costa Mesa, CA 92627
http://www.geocities.com/CapeCanaveral/6389


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ix-inch Telescope Overview with Plywood Cut Pattern


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r r r - rl w ir l w .


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otes:


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i T i " Si r " E i H l r- F r )


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shape... wrap this piece of paper around the dowelso that the ends come together (trail and errorcutting may be required here). The paper will notlay flat! Now trace the outline the edge of the papermakes. Cut close with a hand saw. Sand or file toline.

into the grooves in the dowel.

If the shingles are cut slightly concave (sothey wont rand will fit snugly) they wont have to be gluedin. Replacement will then be easy. If you dodecide to glue them in, use black, 100%silicone adhesive.

Shoving a shingle into the groove in the dowel.

The compass should be set to the radius of theinsideof the telescope tube. dowel, mark all three shingles.

Section A of Making a Telescopehttp://flake/telescope/Section%20A%20of%20Making%20a%20Telescope.htm (2 of 12) [9/6/2001 11:33:23


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NOTE: Above, a close-up photo of my Dobsonian Sun scopebelow) is oto rder--and attach--a2-inch oto1-1/4-inch adaptere


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If the fit is too tight, we may
mailto:([email protected]


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Note: Cut the telescope tube the same length as the focal length of your mirror. Then cut the eyepiecehole back from the front end of the telescope tube by the radius of the tube. That is, for a 10" diametertube, cut the eyepiece hole 5" from the front end; for a 12" diameter tube, cut the eyepiece hole 6" fromthe front end. These distances are for mirrors about 1" thick. If you have a thick mirror (i. e. 2"+) the m 6thick mirrorw/s..1pcut the hole 5" from the front end; a 10" tubewigth 2" (thick mirrorw/s..1pcut the hole42m)Tj

Not:


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iding the circle into six equal segment31.4352 20rcleradius ofircle into syou just drew).


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rin the telescope


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Section "C" of: Making a Dobsonian Telescope


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Front edge of Ground Board (upside down, "planview")--one foot at each corner:

Back edge of Ground Board with foot centered

Now turn the Ground Board right-side-up. Make a markne inch forward (toward the TWO front feet) of the center.Do NOT let this1" forwardconfuse you; this is just anpproximation of the center of the triangle the three feetake. The three sides of this triangle are not equal--the frontde of the triangle--the one with a foot in each corner isnger than the other two sides pointing back to the otherot. A more accurate way to determine this center is to finde midpoint of each side of the triangle and draw a line at a

ght angle to each side toward the inting; the itingsection ofe three lines is r6 ththe center of the triang1" fmed byof tan

lt


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ocker Box, i. e., the same size as the diameter of the lagcrew (1/2"). (CAUTION: Have someone hold down thecord for you while you drill it or it will madly ride up on thet).

On the Ground Board
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Cutting the Cradle Boards And Balancing The Tub

CUTTING THE CRADLE BOARDS

Use the two remaining pieces of Part B for the Cradle Boards.

The Cradle Boards need to be cut to hold the Side Bearings (circles). (Note: Cutting a V-shape io Cu BCrahe


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The telescope s Side Bearings (the circles on theube BoWat 5 18 6.66) sit icircl V-shaped notchtheicircl es on the The to 87 moved up and


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rocker"].

he tpoints wher the tTj /F17 1 Tf -9.83 T" -9.83 T"3)two int tDTs69e). LeTj Cr tpointprotrude14t T*(a litthly-1.rj Crins69e edgeTd


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eep the mirror pulled back against the tailgate during alignment.
http://www.crazyedoptical.com/


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A suitable, clean tub.A drop or two of mild (ivory) dishwashing soap.A box of sterile cotton balls.A 8allon (or less) of distilled water.

Wash your sink, Rubbermaidtub, whatever, thoroughly.

Fill sink, whatever, with room temperaturewater (to avoid thermal shock between the layer of aluminumould help loosen the adhesion between the two surfaces--use only room temperature water

Submerse mirror in water. Swish auound. Let soak.

Replace soapy water with fresh soapy water. Do not hold mirror under a running d (--some people do;


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Frequently Asked Questions (FAQ's)
http://pw2.netcom.com/~rigelsys/Rigelsys.htmlhttp://www.oriontel.com/http://murni.com/coulter.htm


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http://www.skypub.com/


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: How long will it take me to make this telescope?

h, abouttwo weekends, I would guess. I think you will find most of your time spent at the beginni

d end if your project: the gathering of the materials; and the final sanding, painting and
http://hometown.aol.com/billferris/http://members.aol.com/kdaly10475/index.htmlhttp://webhome.idirect.com/~rsnow/http://www.geocities.com/CapeCanaveral/6389http://www.geocities.com/CapeCanaveral/6389http://stargazer.isys.ca/

dobsonian manualv2

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