Repairing an eyepiece focuser

If a refractor has been dropped, the focuser must be repaired.

Tools required:

1.5 mm Allen key
2.0 mm Allen key



First, the two focus nuts will be removed. These are held in place by 1.5 mm Allen screws.






Then comes the lower black knurled screw.






Now the 1:10 reduction gear, the so-called automator, is removed. To do this, loosen the two grub screws; the second is accessible through the hole. To do this, turn the focus drive until the grub screw is visible in the hole.





Then remove the bracket. If a black rubber ring suddenly appears, see the picture above to see where it should go.





The automator was damaged. We removed it from another focuser, which we use for spare parts.





The grub screw shown in the image adjusts the contact pressure of the focusing drive (2.0 mm Allen key). The two 2.0 mm Allen screws shown above hold the pressure plate.