Astro EQ conversion of EQ3-2 (part 4)

My new drills have arrived and I’ve now drilled all the holes for the RA motor mount. It looks a bit like a Swiss cheese. This is the “outside” face, with holes for the motor flange, the four mounting screws, the RJ11 socket for the motor cable, one for a cable tie to keep the wiring neat and an access hole for fitting the motor mount to the telescope mount.

ra-motor-01

The face that fits against the mount has access holes for reaching the motor mounting screws and a large one to make sure there is clearance for the pulley.

ra-motor-02

In fact, having fitted the motor I didn’t actually need the clearance hole, though there’s not a huge amount of space between the face of the pulley and the aluminium channel.

I filed a flat on the end of the motor output shaft for the pulley grub screw to bear on, fitted the pulley and drew the wires through some heat-shrink (as yet unshrunk) to keep them neat.

ra-motor-03

The last step for this motor is to solder the motor wires to the RJ11 socket, after which the entire unit can be fitted to back to the mount.

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4 Responses to Astro EQ conversion of EQ3-2 (part 4)

  1. Kevin Buckley says:

    Hi
    A very informant website.
    I am currently awaiting arrival of an AstroEQ from Tom. I would like to fit equipment to existing motors as i believe this is possible from Stargazers Lounge. Would you be able to go through an instruction as to how this is possible? Do the RJ11 cables clip on directly to the motors? Willthe circuit board within the motor casing be obsolete? I cannot find a visual instruction on how to do this. Will wires need cutting and re-soldering? I am sure i can carry out upgrade if i had some instruction and i am also sure that many other EQ-5 mount owners would find the instructions invaluable. This would provide the confidence to later upgrade to stepper motors.
    Kind Regards
    Kevin

    • james says:

      I believe it is possible to use the standard motor units just by changing the configuration to account for the gearing of the motors, but I’ve never tried it I’m afraid.

      I decided against using the standard motor units because there’s so much backlash in the drive train. You might be able to split the motor and gearbox and put a pulley directly on the motor output which should avoid that problem, but you would definitely have some issues with the existing connectors as you’d have to replace the mounting brackets and remove the outer plastic motor housing so there’d be nowhere for the connectors to go. I don’t think it would be too difficult to unsolder the wires to the motor and reattach them to another connector though — basically you’d end up with the same setup as I have.

      (Should you need it there are some photos of a dismantled EQ3-2 motor that I have posted here, btw.)

  2. Kevin Buckley says:

    Thanks for the reply James
    Would it be very expensive to upgrade the motors? The only thing I’m worried about is that i am not that technical and would not know where to start in splitting motors and gearboxes.
    kind regards
    Kevin

    • james says:

      It’s not that hard to split the standard motors and gearboxes at all. The awkward bit would be adding the new power connectors, but that’s likely to be a requirement anyhow.

      My recollection is that the motors I used weren’t that expensive though. Around £15 each as far as I recall. The timing pulleys probably cost more than that.

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