Electric Focuser Mount, Meade ETX-125 Telescope

A bracket for mounting a Meade 1244 electric motorized focuser kit on a Meade ETX-125 telescope. The 1247 kit for the ETX-125 is difficult to find and the 1244 kit for the ETX-90/105 is more-readily available.

No drilling or permanent modifications of the telescope are required. The bracket is captured by the right side flip mirror knob and the flange around the focuser shaft opening. However, you will need to cut the 1244 plastic shell under the motor and remove the plastic standoff. An M3x14mm socket head cap screw is required to mount the 1244 motor unit to the bracket.

Loosen the set screw of the right-side flip mirror knob and the focuser knob. Remove both knobs and set aside. You will not be reinstalling the focuser knob.

Remove the two screws from the 1244 motor unit to separate the halves of the housing. Set aside the top cover and two internal gears. Carefully pull the motor out of the other half and let it hang from its wires and move the wiring out of the cutting path. I used a milling machine to trim the standoff until it is flush with the surrounding housing. Test fit the 1244 housing to the bracket and trim the housing under the motor until it clears the bracket, telescope rear cover, and the right side telescope mount bracket. You will cut away at the housing until the motor is exposed, however once the motor unit and bracket are installed on the telescope, the cuts are not visible. Do not cut the ribs that hold the motor and prevent the motor body from spinning inside the housing.

Press the spacer into the brass focuser gear. You might need to sand/file the outer surface of the spacer to fit, and then ream the inside diameter of the spacer with a 5/32 hand reamer to fit the focuser shaft. The gear is installed with the set screw face towards the telescope and the flat face away from the telescope.

Reinstall the right-side flip mirror knob. The knob will be installed rotated 180 degrees from the original orientation because access to the set screw is blocked by the bracket.

The focuser can be controlled using the 497 Autostar hand controller of the ETX-125. It is possible to purchase the 1244 motor unit and brass focuser gear separately if you do not need the focuser hand controller.