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ASSEMBLE THE KIT:

If you have any questions, or see anything I haven't covered, please let me know and I'll add that information. Simply email me at densteele@dobstuff.com and I'll follow up and quickly as I can.

SOME SUGGESTIONS:

== FINISHING THE WOOD: There are couple of very nice varnishes, either the brush or spray kind. I like to use the Varathane "spray" varnish. It's available in gloss or semi-gloss. Use #320 sandpaper to prepare the wood, sanding with the grain. After the coat of varnish dries, polish lightly with the sandpaper and spray again. Make sure you remove all the "dust" from sanding. A shammy works nicely. I suggest 4 coats, paying special attention to the "edge" of the wood, as the varnish absorbs into the wood easily. Spray or brush varnish the edges 7 or 8 times.

== STAINS: Many of my "kit builders" have used stains. The Birch ply stains very nicely. Many of the stains have the varnish built in. Again, multiple coats are fine (remember that with each coat, the color may darken).   If you plan to use a stain, tell me and I'll include a couple of pieces of Baltic birch "scrap" to test your color and finish of the stain.


== ASSEMBLY: I like to assemble the scope with "wood screws" only until everything looks right.  I've drilled pilot holes for you.. Since the wood is 3/4" thick, I include  1 5/8 inch wood screws.  If you have a variable speed drill with a Phillips screw driver, it'll be easier to complete the job. The nice thing about using Phillips screws is that the screw driver stays in place. Be sure to use the right screw driver bit, otherwise you'll damage the screw head, making the screw difficult to remove later.

== GLUE: Once the scope is assembled to your satisfaction, you may wish to glue the rocker box. Simply remove ONE SCREW AT A TIME, dip it into Elmer's White glue, and replace it.  I like to use Elmer's white glue. It dries fairly quickly is a "clear in color". You may wish to use the scope for a while before gluing. No harm with that.

== EBONY STAR AND ALTITUDE BEARINGS: Affixing the Ebony Star (ES) to the altitude bearings is easy to do. Again, be sure you have varnished the edge of the altitude bearings to seal the wood. Otherwise the wood absorbs the contact cement and the ES won't bond to the wood very well. Varathane sells a wood "sealer", but I find a few coats of varnish does the same job. Varnish the entire altitude bearing before putting on the ES. If the contact cement drips or runs a bit, it'll wipe off easily. Otherwise, it'll be absorbed into the wood and discolor it slightly.

== SETTING THE LENGTH OF THE STRUTS: Once you're ready, it's time to set the correct length of the struts and cut them. After you have the mirror/cell, secondary/spider and focuser in place, you'll have the dimensions needed to use a neat little software program called "Newt".  You can download Newt here.  Newt will get you in the "ball park", but sometimes the actual strut length is a bit different than the program indicates. I like to actually use the telescope "under the stars" before cutting the strut length. How?? I use adjustable struts, but I don't think that's practical for everyone.  Take a look at item #15 below. Fred, in Bloomington, Indiana, used wood dowels to test the length of the struts and made sure all his eyepieces came to focus. Start out a bit "longer" and slowly down them shorter and shorter until everything works correctly. You don't need to worry about collimation, just get a star image into the field of view, focus all of your eyepieces and you're all set.

== SETTING THE LENGTH OF THE STRUTS 2: Here's an easy procedure for measuring the strut length with a tape measure. Click here.

== MOUNT YOUR MIRROR TO YOUR MIRROR CELL WITH SILICONE. For a discussion of this subject, pictures and instructions, click here.

I hope the pictures and descriptions that follow are helpful. They are in no particular order .

Thanks, Dennis

 
 

 

 1)  I usually start assembling the telescope with the top ring.  Mount the spider and secondary, install the knobs and focuser.

A NOTE ABOUT THE FOCUSER. I've drilled the holes in the focuser bracket and on the top ring so as to mount the bracket once you have affixed the focuser itself to the bracket. You'll notice one hole is larger than the other. This allows the focuser bracket to shift, slightly, so it can be aligned with the center of the secondary.

And a note about installing the Destiny spider. As you assemble the secondary mirror onto the center support of the spider, notice that the "spring" goes on the TOP of the assembly. If you need to move the secondary up/down along the optical axis, you can do so with the collimation thumb screws. Finally, tighten the center thumb-nut for a firm assembly.

Collimation is easy, that is you just adjust the thumb screws without the need to "loosen two, tighten one"!! Easy.

1.1) The underside of the top ring. The hand-knob takes a lock washer. Make it tight enough so there is no "up/down" motion, but that it rotates freely.

NOTE: When you're installing the threaded inserts into the aluminum struts, be sure make allow enough room for the lock nut to clear the top of the tubing (be careful NOT to install the insert too deeply into the strut. If you do so, the threads won't "connect".
 

 

 2) The mirror board. Install the "feet" into the mirror board. The 1 1/2" carriage bolts go into the holes that will attach the struts to the telescope.

NOTE: If I didn't make a mirror cell for you, or if you didn't send me yours to install, the mirror board will be shipped with a 1/4" center hole. Once you've centered your mirror cell, you can use a router (or other tool) to cut a larger center hole if you wish.

As a service for kit buyers, I WILL MOUNT YOUR MIRROR CELL at no cost -- the cut the larger center hole -- just send me your mirror cell.

 

 3) The top side of the mirror board. Note the washers and lock nuts (the washers keep the struts from digging into the wood when tightening the strut).

 

 4) Once the mirror board and top ring assemblies are complete, I use a set of "adjustable struts" to test the optical system. Calculate the strut length here or use this helpful this on-line web-application.

NOTE: I use a "wing nut" (any nut will do) to keep the feet in place. Otherwise, they'd fall off during this stage of the OTA assembly. 

 

 5) Once you've checked the focus in step #4, you can finish the mirror box.  Install the inserts into the mirror box struts and affix them to the mirror board.

NOTE: With these shorter "mirror box" struts you have some leeway, but when installing the inserts into the main struts of the OTA, be sure make allow enough room for the lock nut to clear the top of the tubing (be careful NOT to install the insert too deeply into the strut. If you do so, the threads won't "connect".

 

 6) Affix the top ring of the mirror box.

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 7) The "wood strut" goes onto the mirror box. Install ONE screw in the top and ONE screw in the bottom for now (I've put a "register" mark that defines the center-line of the OTA ring).

 

 8) Assemble the optical tube assembly (OTA) and move into the next step -- determining the balance point of the OTA.

 

 9) I determine the balance point by using a piece of 3/4" PVC tubing. Install a medium weight eyepiece at this point. Be sure to remove the mirror cover if you have one. Mark the balance point with a pencil. This is where the "center hole" of the altitude bearing will go

 

 10) Assembling the rocker box is easy. I use "bar clamps" to keep the sides and front/rear in place. I've drilled pilot holes for you. Use the 1 5/8" #6 wood screws. They are "self-countersinking". Work slowly.

 

 11) Detail of inserting the wood screws. Using a power drill and Philips bit helps save your muscle power.

 

 

 12) Finally affix the bottom. I've drawn a circle on the bottom of the rocker (toward the ground board) to position the laminate. A small bar clamp helps keep the pieces steady during assembly. There is a FRONT and a REAR (I've marked these for you), so orient the bottom correctly.

 

 13) Use contact cement to affix the laminate to the bottom of the rocker box.  Glue the "smooth side" to the bottom of the rocker box.

 

 14) Affix the feet to the ground side of the ground board.

 

 

 15) Install the ground board Teflon. The center 2.5" center carriage bolt is inserted.

NOTE: I use oversize Teflon bearings, here, so the motion isn't "bumpy". Unlike the texture of Ebonystar, the texture of the azimuth laminate is more coarse.

 

 16) Install the ground board. Use the 2.5" carriage bolt, 1.25" fender washer and lock nut. Don't tighten the nut too tightly, leave about 1/8" of play so the rocker box will ride on the laminate and Teflon bearings easily.

 

 17A) Install the altitude bearing Teflon. I usually put them 1" below the top of the curve. You can move them closer for an easier motion, farther away for a bit more sticktion.


17B) PLEASE NOTE: I put a groove on the inside of the rocker box sides. So, when installing the Teflon bearings on the top of the rocker box -- simply install the side Teflon FLUSH with the outside of the rocker box side. The allows the telescope to "float" between the sides of the Teflon while riding on the surface of the Teflon.

 

 18) By now, you'll need to install the Ebonystar onto the riding edge of the altitude bearing. Use contact cement.

 

 19) I usually put a small "brad" at each end of the Ebonystar to help keep it in place.

 

 20) The altitude bearing affixes to the mirror box and forward strut as shown. There is a LEFT and a RIGHT side (as looking from the bear of the ring). In this picture you see the LEFT clamp. The curved corner goes toward the center of the primary mirror.

NOTE: The center hole is located at the "height" you measured in step #9 for the balance point. Now you can drill the hole in the wood strut for the bottom bolt of the altitude bearing, washer and wing-nut.

 

 21) Once the altitude bearings are installed onto the OTA and it is place into the rocker box, it MAY be necessary to "twist" altitude bearing to align it with the sides of the rocker box. This is why I've only installed "one screw" on the top and bottom. Once the alignment is all set, you can install the second screw in into the top of the wood strut.

FINALLY, when you're happy with the "fit" of the OTA in the rocker box, and if you wish, you can remove ONE SCREW AT A TIME, dip it into Elmer's White Glue (I like this glue because it dries clear) and re-insert the screw. This will be enough glue to assure the assembly stays together permanently. 


22) Assemble the counterweight as shown.

NOTE: I include a second clamp for a finder. You can find any number of methods for mounting finders. Some users like to use a Telrad. If that's the case with you, I'm glad to make an extra clamp for the Telrad base.


23) The focuser baffle can take any configuration you wish. I usually put the mounting hole -- centered -- 3 inches below the top. I round the corners. Use the baffle with the textured surface toward the eyepiece.

 

 NOTE:) Here's a good example of a kit assembly. Fred, located in Bloomington,  Indiana,  has put together the mirror box and top ring and then used wood dowels and bungee cords to keep everything together. He'll adjust the length of the dowels (the struts) as needed and then cut the aluminum. Just make sure you've made the wood dowels a bit "longer" than needed. The best way to test the length of the struts is by actually using the OTA under the stars and bring your eyepieces to a focus.

Calculate the length of the struts with this simple procedure. Click here.

 


A good idea for adjustable struts by Rick in Taylor Michigan.  Rick calls these "pseudo struts" (adjustable). The components are:

1) Bottom,  1.5" wooden dowel.
2) Middle, split 1.5" Schedule 40 PVC with hose clamp.
3) Top, Schedule 40 PVC with 1.5" dowel plug.
4) Both ends have 3" lag bolts and 2 washers.

Of course, the diameter of the PVC and dowel can be smaller for your specific application. The lengths of the wooden dowel and PVC pipe should match your calculations for the struts.  Calculate strut length here.

 

 Completed Telescope.
For more information about your requirements:
--Dennis Steele
--Tel: 650-315-6578 (anytime)
--Email: densteele@dobstuff.com		  

 

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