The Saddle
Since the eyepiece of the Newtonian reflector is frequently found to be in an awkward position for observing, it is customary to provide a means of rotating the tube in its saddle or cradle (M in Fig. 9).
A good length for the saddle is about 15". The tube rests in V ways, or the ways may be curved to fit the tube. The center of balance of the telescope must be centered on the saddle. To prevent slipping, two rings of metal, plywood, or thick leather belting (K in Fig. 9) are secured to the tube, flanking the ways; straps of leather or spring brass (L in Fig. 9) hold the telescope to the saddle.
A method of attaching bolts to the straps is shown in Fig. 64; metal straps may be riveted directly to the bolts. The bolts enter slotted metal bars fastened to the bottom of the wooden saddle, and extending out about 1" on either side (see Fig. 9). To reduce friction in rotating, the straps and saddle ways should be lined with felt where they bear against the tube. This material can be held in place with glue or shellac.
With such an arrangement, rotation is easy, and when it is time to
close up for the night, loosening of the wing nuts allows the straps
to be quickly slipped off so the telescope can be removed indoors.
Next- Optical Alignment
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