9.02.2021 Stairway to the heavens?

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 Tuesday 9th -3C cold and very windy. A little sunshine around lunch time.

I was doodling the present, observatory stairs [stepladder] in my mind. When it occurred to me that I [presently] ascend to arrive at the trapdoor. With the outer observatory wall just beyond it. The handrails are literally resting against the low, veranda doors. The image shows an early set-up without the veranda doors or trapdoor.

The trapdoor cannot be lowered until I have completed the climb to gain the observatory floor. Then, unless these doors are wide open, there is still nowhere to go except sideways and backwards. 

I must step backwards to clear the fixed handrails which are welded to the big stepladder. Or, I must stop climbing at the penultimate step. Then step upwards and sideways onto the observatory floor. Which always seems like a physically higher step than between the rest of the stepladder treads. Even though it isn't. It is always an awkward movement. Made worse by the presence of the handrails or when carrying anything.

The image [left] shows the severe limitations in placing the stepladder within the octagon. The big stepladder rises inside the pyramidal pier. Then stops dead against the observatory wall. 

The upper pier cladding had to be cut out like a dog kennel. Just to allow my head to pass unhindered. This followed several, painful collisions! Only much later did I add the present [counterbalanced] trapdoor. Which itself had to be provided with pivoted toggles on which to rest when closed.

Now we move on to the much larger footprint of the expanded building.What if I could twist the whole stepladder in a clockwise direction? Bringing it much nearer to a tangent to the new building's [far more] circular footprint. This would require a new and larger rectangular clearance hole [presently 60cm x 130cm] in the observatory floor. Though now much further away from the mounting, the telescopes and the usual foot traffic area. 

The important detail is that I could continue to climb to the top tread of the existing stepladder. Then simply step straight through the handrails. Onto the observatory floor at exactly the same level. 

The stepladder handrails would provide some limited protection from falling into the large hole in the floor. Though there is now, no longer any need to access the ladder from the side and above. A suitable handrail and three posts can easily and safely protect the entire hole in the floor. 

There would probably need to be some trimming of existing joists. Which must then be boxed around the new hole in the floor with sturdy material. The missing strength must be carried around the hole and continue beyond. Just as it would be in a loft access, trapdoor situation, indoors.

Descent to the ground floor would mean passing backwards between the handrails. The 65° angle of the stairs and narrow [10cm/4"] treads do not lend themselves to forward facing descent. Not unless I replace the aluminium stepladder with a home-built, wooden and/or plywood version. One with a much more relaxed angle [55°?] and deeper treads. The problem then is how much linear space it uses up. 

Such a wooden replacement could be given a gentle bend in the middle. To allow it to follow the lower building's walls more closely and without requiring a curved stair or landing. Nor tapered treads. It could then arrive on the observatory floor parallel to the nearest observatory wall. Providing minimum intrusion into the obs. floor space. While allowing easier access from above and below. A newel post and handrail would provide protection to the hole in the floor. There being no need to add safety overhang as occurs with the metal, stepladder handrails.

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