12.12.2020 Modifying calf rearing Igloos Part 2.

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Judging the size and visual impact of the larger dome in place in the garden required some digital drawing. Also some re-measurement of my existing dome. The plywood dome is 3.3m diameter at the rubber skirts. 3.1m Ø inside the base ring. 

The 16-sided panels lie somewhere in between. So I gain about a meter in overall diameter. Plus increased height inside for the 7" and even more room for my 10" f/8 Newtonian. If I ever finish that.

The downside to all this is the need to move the entire pyramidal pier. Ideally, the centre of the octagonal building needs to move outwards away from the nearby shed by a couple of feet. This would allow better access between the buildings than at present. 

The newly occupied crescent of ground would need to be raised with self compacting gravel to a depth of over 60cm or 2'. Just as I did for the present building. The larger building could usefully be moved forwards inot the garden as well. To avoid having to raise the ground at the rear. Where access for heavy wheelbarrows is much poorer and the ground much lower. Where it rolls gently away to the northern boundary.

I would need to add more concrete anchors to increase the diameter of the building's circular form. Which means more 4x4" uprights and longer floor joists. The question is whether this can all be accomplished without completely dismantling the present building. The plywood cladding is easily removable. Though time consuming because I used so many small screws.

The change in circle diameter is quite considerable in comparison with the present octagon. I certainly don't want the new building to look like a huge mushroom! I would also prefer the building be much more round rather than octagonal. Not even sure I still need a veranda. The area it covers would be lost inside the new building.

I'd like many more sides to make the ground floor of the building much more roomy. This could probably be best achieved with half width , cladding sheets if I get my sums right. I might even be able to save some of the present and nicely weathered cladding sheets for re-use. Having used screws for fixing literally everything together the last time around. Just in case it ever needed to be taken down.

There would be much better access around the huge, pyramidal pier than at present. Working outwards from the existing building would be much safer at the required working heights. The 4x4 uprights would reach the new base ring. Just as they do now. Balancing these tall and heavy posts was a bit of a trial on the last build. Until I had enough of them to safely cross brace.

Where to put the stairs up to the new dome? Do I really want another trapdoor and the rather steep, 70° warehouse stepladder? Should I build wooden stairs outside? Not keen on ducking under the base ring and opening external doors to go in an out. As I do all the time when I'm solar imaging for hours on end. 

Nor do I fancy climbing outside stairs in snow and ice as I grow even older. A more gentle set of wooden stairs inside a larger, round building could be made tangential rather than straight up the middle. I have to climb [literally] inside the plywood clad, pyramidal pier. Then out through a dog kennel cut-out at the top to reach the observatory floor. It works, but means carrying anything up and own is unusually difficult due to balance and clearance problems. A closed stair well on the perimeter could be another option. There are obvious safety and security issues with all of these decisions.

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