Telekit 18 Inch Telescope V2

My 18” TeleKit Project

I ordered the 18” Astrosystems TeleKit on September 16 2008 and received the bulk of the order late October / early November. I also ordered an in-stock primary mirror from Astrosystems [f4.5]. For me, Astrosystems was a one stop shop. I finished the project on January 15 2009 after putting in around 100 hours of work. I had a great time and one day, when I’m retired, plan on building a 30” TeleKit. The 18” TeleKit is sized so I can wheel it out of my office door; I have about ½” of clearance on either side of the transport handles. I’m still waiting on first light because the weather has been so darn cold. It’s been low single digit [F] every night which is too cold for me. Hopefully things will warm up soon. I will update this presentation as time and events dictate.

That’s it for now. Astrosystems [www.astrosystems.biz] provided outstanding support throughout this project. BTW, this presentation is l-o-n-g and probably way boring for most people. So that’s your warning. Otherwise enjoy.

Scott Ghizscottghiz AT yahoo DOT com

http://www.astrosystems.biz/

18” TeleKit Project

NOV 8 2008: Most of the boxes and components arrived in late October. Here they sit in my shop. Truss tubes, covers, and some other parts arrived a week or so later.


NOV 8 2008: My carpeted work table built on top of an old Craftsman Workmate


NOV 8 2008: My workshop with some of the parts scattered about.


NOV 8 2008: Labeled boxes, primary mirror is on bottom.


NOV 8 2008: The shop


NOV 9 2008: Building upper cage. OOPS. Astrosystems sent cage supports for a 16”. Astrosystems sent the 18” supports that day.


NOV 15 2008: Edge grain of an upper cage ring. Nice stuff to work with.


NOV 14 2008: Sanded filter box / focuser mount.


NOV 15 2008: Gluing truss attachments to lower ring of upper cage.


NOV 16 2008: Ground board feet and TeleKit manual.


NOV 16 2008: Gluing up ground board feet


NOV 16 2008: Gluing up ground board feet


NOV 16 2008: Gluing up ground board feet with azimuth brake knob acting as a spacer.


NOV 16 2008: Gluing up ground board feet [again]


NOV 16 2008: This is what I used to fill end-grain voids


NOV 16 2008: ‘Natural’ color worked well without adding pigment


NOV 16 2008: Glue drying on ground board feet and upper cage


NOV 25 2008: Gluing feet to ground board


NOV 26 2008: Masking ground board feet in preparation for laminate attachment


NOV 26 2008: Weights pressing the laminate to the bottom of the ground board feet after applying contact cement


NOV 26 2008: Gluing upper cage together, trying to make it square


NOV 26 2008: Gluing upper cage together, trying to make it square… MORE TAPE!


NOV 26 2008: Upper cage just about ready for urethane


NOV 26 2008: Gluing on baffle stops to filter box


NOV 30 2008: Looks like upper cage, filter box, and ground board are ready for urethane


DEC 2 2008: Beginning assembly of rocker box


DEC 2 2008: Rocker box glue up


DEC 3 2008: About to attach rocker box bottom


DEC 3 2008: Rocker box bottom attached


DEC 4 2008: Flush routing rocker box finger joints… what a mess! Shavings get everywhere.


DEC 5 2008: Rocker box getting done. It looks routed and sanded.


DEC 10 2008: Sanding dust and router shavings get spewed all over the place. This is my technique to keep that stuff out of my beer. Dixie cup over the top… I hope it was a clean cup.


DEC 11 2008: Applying contact cement to rocker box laminate


DEC 11 2008: Using weights to press laminate flat onto bottom of rocker box


DEC 11 2008: Using 3/8” round over router bit on bottom of rocker box. I liked this radius better than the recommended 3/16”. I didn’t want to kick the laminate loose while using the telescope.


DEC 11 2008: Rocker box bottom after round over routing


DEC 11 2008: Upside-down rocker box. Looks ready for urethane.


DEC 11 2008: Flood! Typical when we get 2” of rain or more in a short period.


DEC 16 2008: Rocker box getting first 50/50 urethane coat


DEC 16 2008: Ground board, upper cage, filter box, and accessory board getting first 50/50 urethane coat


DEC 19 2008: Final urethane coat on upper cage


DEC 21 2008: Not bad for a non-sprayed finish


DEC 21 2008: Finished ground board with one of three azimuth roller bearings installed and azimuth break installed


DEC 21 2008: Another view


DEC 21 2008: Filter box blackened on part facing inside of upper cage


DEC 21 2008: Filter box blackened on part facing inside of upper cage


DEC 21 2008: Filter box attached to upper cage and double sided tape applied to inside of upper cage for light baffle attachment


DEC 22 2008: Light baffle [inside painted flat black], spider, and secondary mirror mount attached to upper cage


DEC 22 2008: Another view


DEC 22 2008: Feathertouch focuser mounted


DEC 22 2008: Filter slide with el cheapo filters. Someday I’ll save my pennies and get Thousand Oaks filters


DEC 22 2008: Accessory board mounted. This will eventually have a Telrad attached.


DEC 22 2008: Looking inside upper cage with filter slide and internal accessory board mounted [bolts not yet blackened]


DEC 22 2008: Getting ready to blacken the inside bottom of rocker box


DEC 22 2008: A dope at Home Depot talked me into using a latex primer and latex paint to coat on top of the spar urethane…


DEC 22 2008: I was told, “don’t even bother to sand. This stuff will bond to glass.” Apparently not. I returned both the used primer and used paint for a full refund.


DEC 26 2008: Recoated with a brushed on oil based black paint. Much better results and it dried much less shiny.


DEC 26 2008: Rocker box mounted to ground board


DEC 27 2008: Beginning to build the mirror box


DEC 27 2008: Gluing up the mirror box


DEC 30 2008: Sanding mirror box


DEC 30 2008: Blackening aluminum parts of the 18-point mirror floatation system


JAN 1 2009: Filling end-grain voids of the mirror cell with wood putty


JAN 1 2009: Gluing truss tube stops onto bottom of truss tube clamps


JAN 1 2009: Gluing location posts, mirror sling mount posts, and travel posts to mirror cell


JAN 2 2009: Forming rocker bearing laminate to rocker bearing. Let it sit overnight to make attaching the laminate to the bearing easier.


JAN 2 2009: A screw-up by me makes the mirror cell better? I glued 3/8” t-nuts where no t-nut was supposed to go. I drilled out the threads and created metal sleeved collimating bolt mounts. Very nice.


JAN 2 2009: The other side of this screw-up. I’m actually pretty happy about this.


JAN 2 2009: Using contact cement to attach laminate to a rocker bearing


JAN 2 2009: Making sure mirror cell attach points are accurately placed


JAN 3 2009: Gluing truss tube clamps to inside of mirror box


JAN 3 2009: Truss tube mounts and mirror cell attachment points


JAN 4 2009: Rocker bearings with attached laminate


JAN 6 2009: Miles of sanding in the mirror box with lots of corners and surfaces


JAN 6 2009: Mirror box, upper corner detail


JAN 6 2009: Mirror box, rocker bearings, mirror cell, transport handles and mirror cover ready for urethane


JAN 7 2009: Masking rocker bearing laminate prior to urethane


JAN 7 2009: Small parts getting urethane [tops of truss tubes, truss tube clamps, mirror retaining points]


JAN 7 2009: Mirror cell


JAN 7 2009: Mirror box with mirror cover in background, right


JAN 9 2009: Rocker bearings and mirror cell


JAN 10 2009: Transport handles


JAN 10 2009: Blackening truss tube clamps and mirror retaining points


JAN 10 2009: Finished mirror cover with side pads


JAN 10 2009: Truss tubes getting end plugs glued in


JAN 11 2009: Masking off, preparing to blacken inside face of mirror cell


JAN 11 2009: Drilling truss tubes for connection to upper truss tube plates


JAN 11 2009: Mirror cell, blackened


JAN 11 2009: Mirror cell


JAN 11 2009: Finished truss tube assemblies


JAN 11 2009: Truss tube plates attached to truss tubes


JAN 11 2009: Inside of mirror box blackened


JAN 11 2009: Wiring mirror cell


JAN 11 2009: Mirror box, done


JAN 11 2009: Mirror cell, complete with mirror sling and mirror floatation system in place


JAN 12 2009: Mirror box with rocker bearing attached


JAN 12 2009: Rocker box with altitude roller bearing installed. The other bearing is Teflon on laminate


JAN 12 2009: Mirror box, rocker box, and ground board assembled


JAN 12 2009: Mirror cell [bottom] installed in mirror box


JAN 12 2009: Mirror cell [inside] installed in mirror box


JAN 13 2009: I wanted to power the secondary mirror heater with power from the mirror cell, so I built this little thing to fit in a corner of the mirror box with in-line fusing and DC [N-type] connector


JAN 13 2009: Another view. I built this out of $2 of 1/8” thick hobby shop Mahogany. I doubled the top and put a large epoxy filet on the bottom side attachments.


JAN 13 2009: Mounted in mirror box directly under a truss tube clamp


JAN 13 2009: Close up


JAN 13 2009: View from underneath. The wire harness will pass through a hole drilled in the bottom of the visible truss tube clamp assembly


JAN 13 2009: 18” primary mirror. It’s just a $3000 piece of glass.


JAN 14 2009: Installing primary mirror… yikes! And the telescope is taking shape.


JAN 14 2009: Looking in from the top of the upper cage toward the primary mirror


JAN 14 2009: Top / front of the telescope


JAN 14 2009: Storage / travel configuration


JAN 14 2009: All packed up with truss tubes and upper cage in their storage bags


JAN 15 2009: Assembled with shroud installed


JAN 15 2009: Secondary heater wire assembly going from the top of a truss tube to a DC [N-type] connector which is mounted to and through the light baffle


JAN 15 2009: Believe it or not, after squaring up the optical components, collimation was a snap with a Barlowed laser collimator tool


JAN 15 2009: Secondary heater wire harness passing out of the bottom of a truss tube, through a hole drilled in the truss tube clamp, and finally attaching to the DC connector in the mirror box


JAN 15 2009: Secondary heater wire harness inside of upper cage and passing along the top of a spider vane. Spot directly opposite focuser can be seen for squaring optical components.


JAN 15 2009: Just waiting for first light. It’s been clear but very cold. I’m waiting for things to warm up a little before taking this outside.


Done for now. I should be adding updates soon.

Thanks for looking.

Scott Ghiz

Date post:	14-Aug-2015
Category:	Self Improvement
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Telekit 18 Inch Telescope V2

Self Improvement