Orion Guide to Correctension Installation for Altitude Bearings on Telescopes

Altitude

bearings

Bearing cylinders

Figure 9. Lift the optical tube and place it into the Dobsonian base so that the altitude bearings rest on the bearing cylinders. Orient the optical tube as shown. Do not bump the encoder connector board or vertical stop when installing the optical tube.

To install the XT system, follow these steps while referring to Figures 10 and 11:

1.Select one of the retaining/tensioning knobs and slide the metal washer onto the shaft, followed by the white nylon washer (you will need to thread this washer onto the shaft). This knob will now be known as the tensioning knob. Push the shaft of the tensioning knob through the hole in the left side panel (the one that has the IntellisScope port) (Figure 10). Thread the knob into the altitude bearing until

Figure 10. The tensioning knob, with the metal and nylon washers, goes on the left side of the base, just above the IntelliScope port. The tensioning knob should be tightened until the CorrecTension pads just touch the telescope’s altitude bearing.

Figure 11. The retaining knob on the right side of the base is inserted though the aluminum shaft of the altitude encoder assembly.

the CorrecTension pads on the interior surface of the side panel just touch the altitude bearing on the optical tube.

2.Thread the other retaining/tensioning knob, which we’ll now refer to as just the retaining knob, through the altitude encoder’s aluminum shaft and thread it into the optical tube’s right side bearing (Figure 11). Make sure this knob is fully tightened.

Note: Only the left side panel has a white nylon bushing in the hole for the tensioning knob. The right side panel does not require this bushing.

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