Orion #9918, XT6, #9816, #9950, XT8, XT10 instruction manual Assembly of the Dobsonian Base

1Azimuth encoder board

1Encoder connector board

5Encoder board mounting wood screws

1Brass bushing

1Encoder disk

1Azimuth axis hex-head screw (length 2.25")

2Fender washers (diameter 1")

1 Hex lock nut

4 Altitude bearing cylinders

4Altitude bearing cylinder screws (length 1-3/4", black)

1 Vertical stop knob

1 Nylon spacer (white)

3 Flat washers (2x1/16" thick, 1x1/32" thick)

(Please note: Unless otherwise specified, all images and pic- tures in this manual are of the SkyQuest XT8.)

C

B

L

KM

D

E

F

A G J G

G

H

I

Figure 2. Exploded view of the Dobsonian base.

2. Assembly

Now that you have unpacked the boxes and familiarized your- self with all the parts in front of you, it’s time to begin assembly. The optics of the telescope are already installed in the tube, so most of the required assembly concerns the Dobsonian base.

Assembly of the Dobsonian Base

Refer to Figure 2 during base assembly. The base need only be assembled once, unless you disassemble it for long-term storage. The assembly process takes about 30 minutes and requires, in addition to the supplied tools, a Phillips screwdriv- er, and two adjustable crescent wrenches. You can substitute a 7/16" crescent wrench for one of the adjustable crescent wrenches, or use a pair of pliers.

The azimuth encoder board and other encoder items should be installed, even if you do not plan to use the optional Computerized Object Locator. The smooth motion of the tele- scope depends on the installation of these parts.

When tightening screws, tighten them until firm, but be care- ful not to strip the holes by over-tightening. If you use an electric screwdriver, do final tightening with a standard screw- driver to avoid stripping.

1.With a Phillips screwdriver, screw the plastic feet into the underside of the ground baseplate (A) using the self-tap- ping wood screws provided. Insert the screws through the feet and thread them into the predrilled starter holes.

2.Loosely attach the front brace (B) to the two side panels

(C) with six of the base assembly screws in the predrilled holes. Use the 4mm hex wrench to tighten the screws. The side panels should be oriented so the SkyQuest IntelliScope labels are facing outward. Do not completely tighten the screws yet.

3.Connect the two side panels (C) with the front brace attached to the top baseplate (D) with the remaining six base assembly screws in the predrilled holes. The side of the baseplate with the pilot hole near the square-shaped cutout should be facing downwards. Tighten all six screws firmly.

Encoder board

mounting screw Azimuth encoder board

Figure 3. Installing the azimuth encoder board. Line up the large hole in the encoder board with the central hole in the top baseplate.

4.Tighten the six side screws installed earlier.

5.Attach the azimuth encoder board (E) to the underside of the top baseplate (D) (Figure 3). Insert the modular jack on the encoder board into the square-shaped hole in the baseplate and align the encoder board so that the small slotted hole in the board lines up with the predrilled starter hole, and the large hole lines up with the central hole in

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