28.04.2022 The big [dome] lift could be possible.

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 Thursday 28th 36F. Early mist clearing to yet more sunshine. 

15.02 Afternoon imaging. Seeing conditions are soft and mobile. With a large white patch of sky around the sun. Best image so far.

 Access to the back garden has been improved dramatically since my wife died. Being free to cut back and lower the boundary hedges has widened the drive by about a meter. Previously it was difficult to drive the car in and out without the mirrors being caught in the branches of the hedges! Now there would be no problem bringing in the lorry with its mounted crane. 

 In theory, the new dome could be lifted onto the waiting building. Unfortunately there are still impediments to such a lift. The dome is full of timber and other non-essential stuff. It was a handy place to quickly store things while I worked on tidying the house and garden. Which, after nearly a month of full time work, is still ongoing. It would take less than an hour to clear the dome completely.

 17.24 Back after a trip in the car.

 The new dome's rotation rollers have not yet been fitted. The original plan was to lay a thick ring of plywood on top of the expanded building. This ring was to ensure a stable and level base on which to mount the rollers.

 The present top ring is a fourteen sided ring of 2x6. Which would form gaps on the flats inside the round dome. Making it unnecessarily draughty. Adding packing arcs to close the gaps afterwards would be awkward and probably messy.

 There is also the matter of lowering the dome directly onto the rollers. This would require very high precision in lowering. Literally a centimetre concentricity. Which would be very demanding on the crane driver. Even though he would have radio control. And, he would probably be inside the observatory during the lift to be close to the action. The slightest swing or a breeze would make lowering to this level of accuracy impossible. Possibly leading to roller or dome skirt damage. 

 I think I will need a tapered [timber] support structure which will aid the final lowering. T-stands of timber would work. Wood screwed onto the building top ring. They would have a slope on the outside. Whilst being the same height as the rollers. This will protect the rollers from the narrow edge of the dome as it lowers. While simultaneously guiding the dome into concentricity with the top of the building. 

17.37 AR2995 and the receding pair AR2994 & 4.

 That said, it is not unusual to lift much larger and much heavier objects. To such fine accuracy that fixing bolts can be accommodated. Usually using a tapered crowbar as a guide. I would have to talk to the crane hire business as to the precision they can manage in reality.

 Then there is the matter of removing the old dome first. The crane could easily manage this too. Provided there was somewhere safe to put it down. It must not impede the lifting of the new dome. This just requires I clear the entire parking area. I can then dismantle the old dome at leisure while it is safely on the ground with access on all sides. A matter of unscrewing the plywood segments via literally hundreds of stainless steel bolts.

  It would be great to have the new dome in place. If only to protect the building from the now-undersized, leaking, plywood dome. I would rather avoid another winter with the building and its contents unprotected. The work required to complete the details might be time consuming but can be done later.

 I need to make and fit new steering rollers. Though the original eight would be perfectly adequate in the meantime. Then there is the dome, friction drive roller. Which will probably be essential to be able to turn the larger and heavier dome. The manual, crank and roller drive work so perfectly, with the old dome, that it makes rotation effortless. The larger dome will provide a lower gear ratio. Making rotation even easier.

 The telescopes and massive mounting would need to be removed prior to lifting the new dome. The risk of damage is simply too great to leave them in place. Besides, even if I use the same pier it will have to be moved bodily to the centre of the larger building. Trying to do this with the telescopes and mounting, still on top, would be suicidal! 

 17.54 Still trying. The image is constantly defocusing and there is thermal "vibration."

18.15 Thin, high cloud is dimming the image now.

 Whoops! I forgot to mention the spherical triangular closures on either side of the shutters. These have not yet been completed. They can be fitted from inside the new dome/building.

 It would be good for me to have my new dome project underway again. It has completely come to a standstill. I need an escape from the tedium of constantly tidying the house and garden after the loss of my wife. The creativity and invention required to complete the enlarged observatory is the perfect distraction. I could then relax and do my solar imaging when conditions allow.

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