iOptron GEM28 Manual

For iOptron Internal Use Only
CEM26/GEM28 Worm Play Identification and Adjustment
Tool needed: a set of metric Allen wrench and a
small flat top screw driver, a pair of nose pliers or
tweezers.
1. After open the RA/DEC ring gear cover to
expose worm assembly and ring gear, exam
the worm assembly movement when hold and
rotating the ring gear.
(1) If the whole worm assembly moves up and
springs back down, this is normal for a
spring loaded worm/gear system
(2) If the whole worm assembly moves left/right,
or even gets free at one end, the hinge(s)
may get loose. Go to next step to fix it.
(3) If only the worm itself is moving freely, the
worm end cap needs be tightened. Please
refer to Step 13 to adjust it.
2. Remove mount motor cover.
3. Carefully unplug the motor cable from the DEC
control board.
4. Release two screws and remove the motor
5. Check the worm assembly to see if both hinge
pins are in position. They should be almost
flash with the bearing.
Hinge pin
(1)
(2)
(3)

iOptron GEM28 Specifications

General

Brand	iOptron
Model	GEM28
Category	Racks & Stands
Language	English