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Here you go Terry, Ian's azimuth fine tuner (wood version). The original was made out of aluminum and didn't go all the way around the pier cap and pier as it was held in place with some strategically placed tapped holes in the pier and cap.
It can be made out of 25mm ply scraps and I've not dimensioned the unit as I no longer have my Sampson mount and am working largely from memories that are 12 years old while roughing out the unit design so view the design as nothing more than a guide to a method that works well.
Construction wise the only difficult bit is making the unit fit tightly on the pier and cap, as you need a good level of clench on the pier and cap to overcome the friction induced by the metal to metal contact between pier and cap, adding some grease to the inside of the cap where it meets the top of the pier will help.
Asimov's turnbuckle suggestion for RA altitude adjustment is pretty much what I did, though I made up a custom slip ring for the back of the RA shaft as there wasn't much room to fit it. If I remember rightly (now stretching my mind back to mid 76) the back of the RA drive has a collet that just butts up against the RA drive. If this is correct you could simply tap a hole in to it and put in a heavy threaded eyelet and hook the turnbukle to another eyelet mounted on the pier. Needless to say you'll have to remove the turnbuckle when rotating the RA axis.
Cheers,
Ian
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