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Overnight
I can decide how best to move the RA wormwheel down to the bottom of
the PA. This would give me about another 40mm of southerly movement. It
would also reduce the amount of cantilevering of the Dec assembly off
the top of the PA housing. The 2" drop in Dec height will be useful for
extra dome clearance up high if I ever need to extend the stumpy
dewshield on the straight tubed refractor. Or move the tube so far up
through the rings, for eyepiece clearance, that it collides with the
inside, top of the dome.
Flashback to 2016 when I was still trying to fit the wormwheel at the bottom of the PA.
The next step is to lower the mounting onto the obs. floor to safely remove the counterweights. Then I can move the 11" RA wormwheel to the lower end of the PA. Then I an try the RA motor mounting plate at the bottom of the RA housing to see if it will allow the motor to fit underneath the PA. Which I still doubt whatever I do to the pier and base plates.
The 10mm thick motor plate will fit in any of the four positions at 90 degrees to each other. I just prefer the motor to be underneath the PA for best protection. Not to mention the tidiest appearance.
The
wormwheel and motor assembly will both have to be inverted. The motor
support plate pushes the bottom PA bearing downwards by 10mm. Which
helps to increase motor clearance from the base plate slightly.
I have tried drawing these changes but would prefer to assemble the parts on the floor to see what is really needed to achieve adequate motor clearance.
Rotating the motor relative to the worm is only possible if it can be tucked in tighter to the wormwheel boss. The worm cannot move relative to its wormwheel. Which makes any changes very limited. Even if there was room for the motor under there it would probably need a longer timing belt. Plus the vital mechanical support for the motor in its new position. A clamping ring will be needed to stop the wormwheel slipping off the end of the PA shaft.
Flashback to 2016 when I was still trying to fit the wormwheel at the bottom of the PA. The next step is to lower the mounting onto the obs. floor to safely remove the counterweights. Then I can move the 11" RA wormwheel to the lower end of the PA. Then I an try the RA motor mounting plate at the bottom of the RA housing to see if it will allow the motor to fit underneath the PA. Which I still doubt whatever I do to the pier and base plates.
The 10mm thick motor plate will fit in any of the four positions at 90 degrees to each other. I just prefer the motor to be underneath the PA for best protection. Not to mention the tidiest appearance.
The
wormwheel and motor assembly will both have to be inverted. The motor
support plate pushes the bottom PA bearing downwards by 10mm. Which
helps to increase motor clearance from the base plate slightly.I have tried drawing these changes but would prefer to assemble the parts on the floor to see what is really needed to achieve adequate motor clearance.
Rotating the motor relative to the worm is only possible if it can be tucked in tighter to the wormwheel boss. The worm cannot move relative to its wormwheel. Which makes any changes very limited. Even if there was room for the motor under there it would probably need a longer timing belt. Plus the vital mechanical support for the motor in its new position. A clamping ring will be needed to stop the wormwheel slipping off the end of the PA shaft.
Click on any image for an enlargement.
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