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Esprit 100ED focusser issues.

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Started a session last night that  once the sequence was going seemed to be going well, the initial auto focus in NINA looked a bit  odd but not to conderned as focus looked good I carried on.
After a few images it did anther auto focus and although it carried on it looked really bad and also the resulting image was not properly focussed.

When I went ut to check the scope I disconnected the auto focusser so I could turn it by hand using the focusser knob the focusser tube just clunked in and out about 6 or 7 mm back and forth like it was massive backlash and refused to actually then move any further and would not rack in or out, just this 6 or 7 mm movement back and forth. I could even move the inner tube back and forth this amount by hand without the knob moving.

This was obviously the issue so shut everything down and brought the scope inside,

Had to strip down the whole focusser, and still not sure exactly what was wrong as basically stripped it down (Everything including all the small 2 or 3 mm little ball bearings and the 3 bigger ball bearings, cleaned everything, and re-assembled giving the ball bearings the lightest of oiling with very fine oil (literally a drop or so) and all working fine again.
I managed albeit 2:30 am to get it back up just to check the focussing and it auto focussed just perfect several times.

Now whether any oil at all is recommended I am not sure hence making the oiling very sparingly as I guess a lot of oil will be counter productive as the 10:1 spindle that the focusser attaches to is ultimately only friction driven to the larger spindle that drives the rack on the focusser and so does not want oil on it. Nut a little oil seemed to help otherwise felt quite notchy.

All working but don't feel confident this will not come back to bite me later down the line.

In my mind this is the part that is failing.

Can you get spares like this or do I need an upgraded focusser altogether ?


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