Hi
Thought I would post a quick summary of my version of the “mini” remote observatory. Not 100% finished but close – just need to complete insulation and tidy up cabling. My objective was quick, simple and cheap. I do have a reasonable workshop which streamlines some things but nothing here is complicated. Hopefully this adds to the library of ideas for budget observatories.
The closed size is approx 1200mm x 1200mm x 1500mm tall. It could have been significantly lower if not for my need to maximise viewing angles. Sadly it most resembles a blend of doghouse and outdoor dunny but is also neat and simple.
Hard to say how this will hold up in the weather but I think it should be ok if paint is kept fresh. Light rain has been no problem but remains to be seen how watertight it is in a real storm.
Pier
140mm x 6mm steel pipe welded to 10mm plate plus very short rat cage for minimal flex topped by brake disk mounting plate. The short cage means access to the bolt for Skywatcher mount requires a spanner but is simple enough.
Enclosure
The observatory currently houses an AZ-EQ5 and small refractor or C8 SCT but was designed to (hopefully) accomodate an EQ6R-Pro swinging a 5 inch refractor or 200mm newtonian. Upgrading to an EQ6 would simply required the brake disk be replaced ($20-30).
The low height of the base enclosure relative to the installed mount is critical to maximise the telescope swing radius relative to enclosure footprint. This enabled the enclosure to accommodate a decent size scope while limiting footprint dimensions to 1200mm minimising the number of sheets of ply required. The low base enclosure sides also allows access by simply stepping over the wall eliminating the need for a door.
Enclosure is framed with cut down framing timber (H3 for base) held together with 65-75mm screws. Cladding is Bunnings 6mm structural ECO-Ply simply nailed to frame. Much cheaper than marine ply but still uses waterproof glue unlike interior ply. In the interest of re-use and cost saving I am using reclaimed polystyrene for insulation.
The slide off roof utilises heavy 1200mm drawer runners. These are rated for 125kg. Not sure I would load them to that but they are plenty for this application and do not require additional support.
Waterproofing was a major concern. The top overlaps the lower section on all sides to facilitate this. The removable “door” is framed with aluminium strips for waterproofing and faces south which will seldom receive direct rain at my location.
Cost
Manufactured goods are cheap but basic materials are just ridiculously expensive and screws, paint and bits n pieces would be another $100 if you don’t have them already lying about. Adds up fast even for small jobs but still small beer compared to everything else in this hobby:
Pier - $110
Concrete - $100
Framing Timber - $130
Ply - $160
Runners - $100
Approx Total - $600
Build Time
After several days googling ideas and roughing out the design the build took about a week:
Fabricate pier - 1 day
Excavate and concrete pier - 1 day
Build box - 2 days
Paint - 2 days
Assemble - 1 day
