Motorised focus for PST solarscope

[Photosbykev]

A simple mod for the Coronado PST Solarscope to motorise the focus so I can keep my hands off the PST for critical setting of the focus.

It's important to say that the PST is completely unmodified by this addition.

PST Solarscope motorised focuser - YouTube

I've mounted the PST in an aluminium channel primarily so I can have the skywatcher dovetail on the side of the PST. This allows the eye piece tube and CCD camera to be positioned above the PST rather than hanging off sideways during normal use on an EQ3 Synscan Pro mount.

The aluminium channel is then used to provide a mounting location for the Orion Accufocus motor system to avoid any damage to the PST. The gearing is 1 : 1 and is made from a Como/MFA multi ratio gear kit. The adaptor shafts to connect the gears to the motor and the PST focus knob have been machined up to suit the various diameters and small grub screws are used to lock the adaptors onto the motor and PST focus knob.

[Merlin66]

Kev,

neat idea!

well done

[MikeWilson]

That's brilliant. Where did you get the little cogs and chain from, Kev?

[Photosbykev]

That's brilliant. Where did you get the little cogs and chain from, Kev?

I bough a multi ratio gear kit from RS Components http://uk.rs-online.com/web/p/products/2396886/?searchTerm=239-6886&relevancy-data=636F3D3126696E3D4931384E525353746F636B4E756D626572266C753D656E266C663D59266D6D3D6D61746368616C6C26706D3D5E5C647B337D5B5C732D2F255C2E5D5C647B332C347D2426706F3D3126736E3D592673743D52535F53544F434B5F4E554D424552267573743D3233392D363838362677633D4E4F4E4526 but I've found a kit with less gears here Plastic Sprocket Set

I did think I might want to change the ratio but 1 : 1 is about right using the Orion Accufocus motor