Tune up guide for the skywatcher 1.25" basic focuser
The Skywatcher Basic 1.25" Focuser

The basic focuser mechanism fitted to the Skywatcher 130 and SkyHawk entry level telescopes amongst others is a simple but reliable focuser made
almost entirely from plastic. It can however be tuned to improve its functionality by a few simple procedures which I have outlined in this simple to
follow step-by-step guide.

This particular focuser was acquired for a project in restoring an old telescope on a budget and I wanted to get the focuser to perform as well as possible.
The telescope being restored was unable to accept anything other than a basic 1.25" focuser due to its mechanical layout.

Skywatcher Focuser Step-by Step Guide
The Skywatcher 130 Focuser The Skywatcher FOcuser Removed from its OTA Removing the pressure spring screws
Although it is not required to remove the focuser to carry out tis step by step guide I would recommend removal to avoid any risk to the secondary mirror.
Be careful when working near the secondary and make sure you remove any watches or rings to prevent scratches and damage to the secondary mirror as well as the internal finish of the tube.
Here is the focuser removed from the optical tube. This particular focuser has a small cut out on its mount ring which was applied for fitting to a TAL telescope. Remove the two small Phillips screws underneath the focus wheels. When these are removed the internal mechanism will drop out so carry out this work on a flat clean surface.
Reoving the pressure spring plate Removing the tensioner Removing the focuse wheel spindle
Remove the small metal plate. This is the plate which holds the focuser mechanism in tension. Remove the small silver colored spring plate. The focuser spindle will now fall free. This focuser showed no grease in any of its components but they are normally greased with something that looks like tar.
Removing the focus draw tube The focus tube rack cleaning The focuser body cleaning
The focus drawtube (the silver tube) will now pull free from the focuser body. The drawtube has a moulded set of teeth on it. This example showed no grease but normally it has a thick grease like tar. Remove the grease using hot water and washing up liquid. Avoid degreasing agents as they will mar the finish of the chrome paint. The focuser body. This example showed no grease but normally it has a thick grease like tar where the focuser spindle is seated. Remove the grease using hot water and washing up liquid. Avoid degreasing agents as they may affect the plastic.
The focuser tension pad Replacing the focuser tension pad Lithium grease and focuser elements
Inside the focuser body you will see a small pad of felt. This acts as a tensioner for the focuser drawtube and some examples of this focuser will show that the pad is either missing or it has slipped and allowed the glued back of the pad to jam the focuser up or make the focus drawtube very stiff. A worn pad will also mean the drawtube is 'sloppy' in the focuser body. On this focuser the felt pad had curled over causing the focuser to jam. The original pad was removed and replaced with a wide strip of felt on the top of the focuser body so that it would be opposite the rack of the focuser drawtube.
The felt was run over with sticky tape to remove any loose particles before being glued into place.
Lithium grease is ever your friend for these tasks. This tub was acquired from a local mountain bike shop for the princely sum of £3.00 and is sufficient for a lifetime of dabbling with astronomy equipment.
Greasing and replacing the focus drawtube Greasing the focuser spindle Replacing the focuser spindle
The rack part of the focuser drawtube is lightly smeared with lithium grease and reinserted into the focuser body. Similarly the cog on the focuser spindle is also smeared with lithium grease. Replace the focuser spindle......
Replacing the tension plate Replacing the tension plate cover Adjusting the tension plate
....and replace the small sliver colored spring plate... ....and replace the small metal plate. Replace the two small screws. DO NOT OVERTIGHTEN. By careful adjustment of these screws applying equal pressure you can adjust the tension of the focuser to provide a relatively smooth and secure focusing action.
  The skywatcher 130PM focuser reinstalled  
  The focuser can now be reinstalled onto the optical tube. The two small screws may need a slight tweak once you have an eyepiece in place to fine tune the action of the focuser.  
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