~o~
Thursday 16th 47F/8.3C. The forecast is mostly cloudy. With a NW wind.
I have a flu and Covid jab at 4pm. The Ryet saddle should be available for pick-up in the village by then.
Up at 6am after a rather sleepless night. I must have dozed off at the computer yesterday afternoon. So sleep was hard to find last night. I decided to be constructive and make the most of this free time. By imagining a series of gantries. For lifting the carport roof. I have a whole variety of ladders. Which can be safely pressed into service. The exercise must be very safe. So overkill is the order of the day.
The first lift is rather close to the big shed. Which limits my options for resisting longitudinal toppling. So I shall use my 5m long, single stretch, roof ladder as the gantry beam. I bought this ladder at a slight discount as damaged goods. Following the great storm of 1996. I needed a safe means of accessing our damaged roof. So a single, long ladder, as part of a damaged double, was fitted with a ridge hook. The same ladder can now provide the gantry beam. By reaching clear over the carport roof.
The legs of the gantry will be opposed ladders. Leaning against each other and lashed at the top. That solves the height problem and provides massive resistance to lateral movement. Becoming an asymmetric tripod with the beam.
I have regularly used opposed ladders as A-frames for lifting heavy weights. In conjunction with my cheapo chain hoist. The picture shows my lifting my massive, home made telescope mounting onto a temporary work stand. The mounting weighed a couple of hundred kilos. Much the same as the carport roof. Note that I used lifting strops for safety. Rather than employing rope of very doubtful strength. Little of the rope, in the usual outlets, has its breaking strain clearly marked.
The chain hoist will be suspended from the ladder beam on a strop. Just beside, but clear of the A-frame ladders, for the necessary clearance. As one side of the carport roof lifts in an arc of 3m radius. Pivoting on the ground on the far side gutter. No, I'll leave the rollers in place. To allow the roof to move nearer the shed as it is lifted. This will avoid it trying to pull the ladders over. The first pair of carport legs can then be safely bolted into place. With the carport roof now tipped up at an angle.
The second lift is much more critical. Here the carport roof is brought up to horizontal to its full height. A little over 2m at the gutter. With the feet of the first pair of legs resting on the ground. I will now have to support the ladder beam at about 3m height at the opposite end. As well as providing end resistance. The chain hoist is moved to the other side of the carport. To be hung from the raised gantry beam ladder. The carport roof must be able to reach its full height beneath the ladder beam.
The second pair of legs can then be bolted to the heavy, carport gutters. These are the main structural elements and are joined by the arched roof trusses. The arched roof provides more clearance for vehicles. Four legs avoid car doors banging against the carport legs. All the steel is heavily galvanized. The heavy, 5m ladder is visible in the image above. Resting against the shed wall.
I shall, of course, provide pictures of the lift. It will all be seen by one of the security cameras. I can lift single images. Or even videos from the recording.
8.00 It is almost light enough for a walk now. Uniformly grey, with the hedges beginning to move slightly in the wind.
8.40 Back from my walk. Two noisy chevrons of geese went over. I could hear the distant birds of prey calling again. Though nothing was visible.
10.10 All the plans of mice and men.. Back indoors for a rest and to cool off. The 5m ladder isn't long enough to reach right over the carport. Nor can I find any way to resist the A-frame. From leaning towards the carport. A separate, leaning ladder, used as a brace, gets in the way of the carport.
A-frames work fine with a vertical lift within their footprint. Not with an outboard load. The shed could provide an anchor. If I drilled one of the vertical timbers. To what end? If the ladder isn't long enough to support it beyond the carport. Don't trust dreams?
I could use an A-frame and chain hoist vertically. By extending the carport with a central, cross beam. Used as a lever. The A-frame would need to be tall enough. To allow the added beam to rise high enough. I could stack a load of concrete foundation blocks on the ladder's extended feet. That would improve the stability. The carport could roll on the added wheels. To avoid out-of-perpendicular loading. I don't have any very long length of timber. Ladder would be too bulk to lift within the A-frame. So it's back to the drawing board.
~o~
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