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Gday Dan,
thanks for taking an interest. I was pretty sure my initial rough alignment was within 2 or 3 degrees of the SCP given that it is clearly visible from my viewing site on a dark night. I even have a"meridian line' painted on my slab, set at an angle of 167 deg east which is the direction of the SCP from here as we have a magnetic declination of 13 deg. So I got really frustrated when the slew kept hitting what seemed like limits of some sort at around 100 deg(east) and 260 deg (west).
You could see the mount was still trying to slew but going nowhere.
At the weekend my son-in-law came for a few days and he knows his way around this stuff and we started from scratch and tested everything and concluded that it was a slew limit but we could not figure what was causing it - initially we though it was "gravitational" due to the angle of the mount base on the wedge plate but no matter how we tilted the tripod,the limits were still there - and when we demounted the wedge and tried the mount in alt-az,the mount spun the full 360 deg - ?????
You will never guess what it was......I bought the wedge basically as new but second hand and it is in perfect condition BUT,someone has removed two of the "captive" threaded bolts at some point and on re-assembling them to the wedge has forgotten to put the 2mm washers back onto the bolts - result..... the threaded bolts protruded just far enough into the base of the mount to interfere with the mount AZ motor mechanism and as it turned out,the slew was stopping each side exactly opposite the position of the bolts on the wedge. Would never have found it without a slow and step by step analysis. The mount now slews 360 deg in EQ mode if required and I have done a few daylight dry runs and have succeeded in both EQ and Polar alignment .So the major problem is out of the way and I need a clear night or two to check it out in real time and see if I still have a pointing accuracy issue.
Rgds
Ron
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