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

Telekit 18 Inch Telescope V2

Self Improvement

telekit project

astrosystems telekit

telekit manual

gluing feet

masking ground board

upper cage ring

lower ring of upper

gluing truss attachments