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Vixen GP-D2 upgrade kit

Markus Noga has designed this excellent kit for TeenAstro with a Vixen GP-D2 Mount.

The kit contains all files and parts that are required for modifying a Vixen GP-D2.

Supported Motor :

Nema17-400 steppers are coupled with the worm shafts via a belt drive

The kit support these motors: Nema 17 Bipolar 0.9deg 36Ncm ( 0.9A 5.4V 42x42x40mm

These motors have been tested and works very well with TeenAstro.

Motor housing:

Markus has made a 3D-printable housing for this 2 motors that doesn't need any mechanical modification on the Vixen GP-D2:

The 3D print design for stepper case can be found here (*.stl), if you want to modify the stepper case the tinkercad project file is here


other elements

  • 2x GT2 pulley with 16 teeth and 5mm bore for the stepper axis
  • 2x GT2 pulley with 48 teeth and 6mm bore for the worm axis
  • 2x GT2 belt 140mm
  • 8x Screw M3x8 to fix the stepper in the case
  • 1x Screw M6x35 to fix the RA stepper case to the mount
  • 1x Screw M6x16 to fix the DEC stepper case to the mount
  • 2x DSUB9 male up to 3 Amps
  • 2x SUB-D Mounting kit

 Soldering the Stepper Wire to the SUB-D connector

  • Solder the wires for one motor coil to pins 1 and 2, and for the other coil to pins 4 and 5.
  • It doesn’t matter which coil you put first, switching the coils will just invert the direction of the motor.
  • Switching two wires for the same coil also just inverts the direction.
  • You can correct for this in the „direction of rotation“ software setting.
  • If your motor came without a data sheet, take out your trusty multimeter and measure the resistance for a pair of wires.
    • If they have low resistance of a few ohms, congratulations, you have found a pair connected to the same coil.
    • If they read megaohms of resistance, you have wires connected to different coils.
    • Hold on to one wire, and try the others until you have found your pair.

****Thanks to Markus for this great Contribution****