FEATHER TOUCH FOCUSER MODEL 3545
Care and use of the Feather Touch 3545
The Feather Touch 3545 was a collaborative design effort between Telescope Engineering and Starlight
Instruments for TEC’s line of fine refractors. It was designed to provide the user the with the best possible
control while focusing using a 9:1 fine focus reduction assembly along with other features that make the use
of the telescope simple and functional. All efforts were taken to design it with the best available materials and
technology to achieve long-lasting functionality and reliability.
Part Description
6.1 OTA Focuser Mounting Flange
6.2 Focuser Locking Collar
6.3 Locking Collar Stems
6.4 Tension Adjustment Screw
6.5 Finder Base Screw Holes (Plugged
with (2), 8-32 Button Head Screws)
6.6 Focuser Housing
6.7 Coarse Focus Knobs
6.8 Fine Focus Knob
6.9 Draw Tube with mm scale
6.10 Draw Tube End Cap
6.11 Draw Tube End Cap Locking Screws
6.12 Eyepiece Collet Locking Nut
6.13 Eyepiece Collet Sleeve
6.14 Plug with TEC logo
Description of Design Features
1. The Feather Touch 3545 achieves excellent focusing capability
using a 9:1 Planetary Reduction Assembly coupled to a fine focus
knob (fig. 6.8). The fine focus knob should be used once the image
is close to focus and final tweaking is required.
2. The two coarse focusing knobs (fig. 6.7) on each side of the
focuser allow quick rough positioning of the eyepiece or imaging
equipment. They are coupled to the rack and pinion set and the fine
focus knob.
3. The assembly incorporating the focusing knobs, the pinion and
it’s housing is called the pinion assembly (not shown). This assembly is attached to the focuser housing using (2) 6-32 socket head cap
screws. The position of the pinion assembly relative to the rack, is
precisely adjusted by Starlight Instruments using 4 flat bottom set screws (internal to the pinion assembly) to
provide the minimum amount of backlash between the rack and the pinion for ease of operation. The other
adjustment that is made is to align the pinion axis to be parallel to the rack face.
NOTE: It is possible to reverse the pinion assembly for left handed preference but Starlight Instruments does not recommend the user reversing this assembly because of possible misalignment resulting
in a loss of performance or possible damage.
Please contact Starlight Instruments or TEC if this change is desired.
6.1
6.2
6.5
6.3
6.7
3
6.4
6.11
6.12
6.13
6.14
6.7
6.8
6.6
6.9
6.10