Mostert's Mill
02 March 2023:
Well, the sails are up at Mostert's Mill! Much planning had gone into today, not least the wind factor. It looked as if tomorrow, Thursday would be less windy, but Johannes Uys of MME, in charge of the rigging and craning, was confident, particularly as the wind was coming from directly behind the Mill. As it happened the wind did abate at the critical time, although I did battle to keep the bare second stock square in the mortise as it was lowered in! Johannes had calculated that water in a flow-bin hung from the front of the Poll-end, plus the fully assembled outer sail in its mortise closest to the end, as suggested by Paul Moonie Kemp, would balance the assembly, if slung just outside of the overhang of the thatch roof. The water was running in slowly from a domestic garden tap, so we added three chain-blocks and any heavy rocks we could find. Eventually it was possible to lift the tail bearing with a finger, and we were ready to lift, swing away from the tower to an open space over the threshing floor, turn it 180 degrees, then feed it carefully into the opening at the front. Then we discovered we'd mis-calculated the height of the pillow-block that the stone bearing rests on. It was too high! We compromised and laid the block temporarily on its side and lowered the stone bearing, already strapped to the wind-shaft, into place. The crane could then lift the other sail-stock at the end already assembled with lattice-work for the sail, and the bare half could be lowered through the other mortise and wedged when it came to rest on the Stock shoulder block. Pilot John then rushed home to collect the decoration for the end of the Wind-shaft so I could install it. Straight Jon can now assemble the fourth set of lattices! The third lift of the crane was the Brake-pole, much easier to lift with a crane with its long outer section and operating chain! So Jamie the Scottie's mate is 7m in the air! We drilled a hole for the anchor chain in the end of the tail-pole, primed it and then drove in a 40mm PVC tube so the chain won't wear the soft spruce. Last thing we strapped the sails back against the Long Stretcher in case of being tail-winded, as we can't 'Wind the Cap' into the prevailing wind from the south, until the fourth sail is assembled. The assembled end will swing to the bottom if the two guy ropes at the ends of the now horizontal sails are released!
24 January 2023
Now Mostert's cap is facing square on towards Cape Town and the traffic coming from that direction! As soon as the builders started working again, Rob Uphill from Bruce Dundas arranged for the remaining scaffolding to be removed and we could 'wind the cap', to test whether there might be any snags between the stationary wooden curb, made of Eucalyptus paniculata, the hardest of all the gums and a gift from Rustenberg Wines, and the moving parts of the cap. The Capstan winch isn't quite finished yet, so Pilot John and I rigged up the chain-block between the eye in the Tail-pole and the successive rings set in concrete around the tower. It was hard work, but we worked out a plan where each of us took turns to grab the operating chain and walk backwards as far as the chain allowed, then went to the front again and pulled again! We turned it about 300 degrees and we're happy inside, but there are places where the Long Braces rub against the tower. We marked these with chalk and met at midday with Architect Long John Wilson-Harris and Rob to discuss this problem. We experimented at the end by applying more tension from the Hangers we assembled last time. First I tried moving the Hanger outwards on the Stretcher. That had little effect and looked out-of-place. We then used the chain-block to pull upwards from the hook on the Hanger and hooked the shackle in higher up the chain. This had the effect of pulling the Braces away from the Tower. Now we must 'wind the cap' again (preferably with the Capstan!) to see if that has cured the problem! Earlier, Straight Jon Stevens from Floorscape who made the Cap-frame was there, doing some assembly of the Sail-bars on the Stocks, but that wasn't as easy as we thought. Johannes Uys from MME, who will do the lifting, also met on site and we discussed how we will insert the 6.5m Wind-shaft into that small opening at the top, only being able to hang the shaft from the crane towards the outer end. We decided that we will assemble the entire outer sail through the Wind-shaft to add weight to the outside, and additionally hang a 'flow-bin' (a 1000 litre water-tank enclosed in metal mesh) to the outer end, and add water until the assembly balances. Then the shaft can be fed in and through the waiting Brake-wheel in the Cap, and on to the two granite bearings (themselves a gift from JA Clift in Paarl). There was one other job, to refit the fourth 'Klapmuts' we took off and damaged slightly last time. We are making progress!
20 July 2022
Lots going on at Mostert's Mill, thatching over the cage which was finished last week is now well advanced. A second truckload of thatch arrived from the Riversdale area today and took a while to offload, into the Threshing Floor area. While the thatchers from JNA Thatchers were doing that, Chairman John and I fitted the 'Cap Ladder' which will give us access from the Dust-floor into the Cap Frame. That involved drilling a 20mm hole through the left-hand Sheer, with John doing most of the work! We had some accurate measuring to do, so that Kimon in Hout Bay will know exactly where to turn the section round for the neck bearing. He's very happy with the way the huge piece of Sugar Gum is drying out. John and I then went to look at some Teak pillars we'd been promised early in the restoration. We were offered three, but when asked what our first prize would be, we said five, two need to be doubled-up for the Hurstings, the pillars which support the weight of the Millstones on the floor above. When I went back with my vehicle to collect them, five were in the pile ready to load. Thank you Henry! We are holding thumbs for tomorrow. Sven, our main supporter in the Netherlands is going to look at a pair of French Burrstones which are available. If he's happy with them, he'll use Crowd-Funding money to buy them and ship them out to us.
04 April 2022
Work has started, at last, on the Tower of Mostert's Mill! Bruce Dundas Builders are putting up scaffolding over which they plan to stretch a big tarpaulin so they can work dry, until they have the top of the tower ready for all the wooden components we have been making. Their brief for the moment is dealing with the cracks in the plaster outside and completely re-plastering inside. Today we had a site meeting, working out the Critical Path Analysis of getting the working parts on site, assembling them and lifting them into position with a 30-tonne mobile crane. The first visit of the crane will be for the Curb, which is fixed to the top of the tower, then the whole Cap Frame, then the 12-metre Long Stretcher, the Vertical Shaft and the Brake-wheel. Five lifts should be possible in one day. Then the Thatchers can make the framework for the roof and thatch it. Unfortunately the wood for the Wind-shaft is still drying out, so that will have to be fitted through the front, and through the suspended Brake-wheel. It should be possible to refit the sails at that stage. All very exciting!
6 December 2021
Mostert's Mill progress! Picking up from last week..... Jon has turned a pile of old scrap beams into a Work of Art! Meanwhile Mike is using his Engineering skills to bring out the best in his 'slice of the cake'! I said Jon needed the roof rafter half-rings to tenon into the Sheers, then he could cut off the Outriggers to the right length and form the fancy ogee ends in them. He also needed the Short Stretcher to build up the Rear Gable which will have a window in the middle and Storm Hatches on each side.
01 November 2021
It's about time for an update on the progress on Mostert's Mill. First, the all-important permission from Heritage Western Cape to proceed with the restoration has been received. A copy of this and the plans must be on site throughout the restoration for any Official to inspect. HWC didn't require anything with respect to the working parts, so I've been pressing on anyway. Work is proceeding on three fronts, Mike here in Grabouw is busy with the Curb rings. He's been on holiday for two weeks, back now, so I expect lots more progress on that front! He'd thicknessed and cut many of the arcs before he left. Jon in Cape Town is busy with the Cap Frame. The two long Sheers needed scarf joints to make them long enough. He is attaching with tenon joints the Outriggers to them and making the fancy 'ogees' at the ends. He's busy with the Tail Beam which supports the heavy stone bearing at the back of the Wind Shaft. Here at home, I've used up 9kg of Epoxy resin on the 'shakes' in the Spruce beams, and I'm happy with them now. Over the weekend I've been busy with the scarf joint in the middle of the Long Stretcher which will stick out on both sides of the Cap, for turning it into the wind.
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