The project is to convert a Meade LX50 to OnStep GOTO. The issue is there is visible periodic oscillation in the worm gear. I removed the original clock drive shaft and measured it to be 3/16. I replaced the shaft and left about 1/2 inch to connect to a flexible coupler. The stepper drive motor was mounted on an adapter plate, which was in turn mounted about an inch from the housing. Adjustments were build into the adapter / motor mounts such that the motor shaft may be be aligned to the gear shaft. This appears to be in proper alignment.
First observation: The total the connection is: Gear - shaft - 1st coupler - intermediate shaft - 2nd coupler - motor.
Second observation: The motor - 2nd coupler - intermediate shaft all rotate smoothly.
This issue is the gear - shaft - 1st coupler have a visible in / out oscillation once per revolution.
My speculation is the replacement worm gear shaft is not holding the worm square to the gear, thus producing a wobble.
Does anyone have experience with this?
I have a modest machine shop and am willing to create a improved housing / mount for the worm gear. Does anyone have access to a best practice implementation for worm housings? Dan