I have an older meade LX2000 EMC 10
The main problems encountered with the mechanics of the telescope centre around
the mechanical swarf, grease compound, the liberal use of grease and the quality
of machining of the main DEC and RA gears.
1. Remove the motors from the telescope. Be careful when removing either
motor as there is a compression spring between the motor mounting frame and
the worm shaft assembly.
The RA motor is located under the telescope body, removing the 4 screws and
2 Allen bolts will allow the bottom cover to be removed, thereby allowing access
the the 2 Allen bolts holding the motor in place. Unplug the motor from the
main PCB before removal.
The DEC motor is in the the fork arm containing the clutch and fine DEC adjustment
control. (Never to be used with power applied to the scope). Remove the 3 small
Allen screws holding the plastic cover plate in place and the DEC clutch knob
to allow access to the motor. Remove the RJ45 connector located inside the telescope
fork arm. Then remove the motor by unscrewing the 2 Allen bolts holding the
motor in place.
2. Remove all grease from the motor worms, especially around the RA motor's
magnetic pulse detector and the permanent magnet built into the worm shaft.
3. Remove all grease from the main DEC and RA gears, making sure to clean into
the gear teeth.
4. Lightly re-grease with a Molybdenum Disulphide based grease (Castrol MS3
is great for this application if you can get it)
5. Assemble in reverse order. But before doing so, carry out the electrical
adjustment above then, (a) relocate the the RA and DEC control PCB's in the
vertical plane thereby gaining access to their respective backlash Allen screws.
Adjust for 20thou max clearance when in final position. Note:- the DEC adjustment
screw has to be replaced for a longer unit complete with a thin bolthead as
this adjustment has to be carried out with a spanner....there is no room for
an Allen key adjustment here.
6. A drop of Loctite must be applied after adjustment.
7. The final part of the process is to run in the gearing. Apply 12 volts to
the motor wires, either at their respective plugs or to the motor direct. Allow
to run for 2 to 3 hours in each direction by reversing the battery polarity
to bed the teeth engagement. Remember to release the clutches.
Dec 28, 2011 |