Restoration Update 9 – Mostert's Mill

2022 Restoration Update 9

On 9 March 2022 we received the welcome news from the Department of Public Works in Pretoria that we could go ahead with the full restoration of Mostert’s Mill. While much of the wooden machinery inside the Mill has been manufactured over the past months, now for the first time since the fire we could start work on masonry repairs and on the Mill furniture – doors, windows, shutters, the two wooden floors and their support beams and access ladders. All these architectural features need broad, official heritage approval. (The wooden machinery did too, but there is no-one in South Africa who knows what the original looked like other than the Friends of Mostert’s Mill, so we were left to get on with making those components by ourselves).

Masonry Repair

Masonry Repair John Wilson-Harris, the heritage architect on our Restoration Team, had already drawn up specifications for the repair of cracks in the plaster layers inside and outside the conical Mill building. This work has been contracted to Bruce Dundas (Pty) Ltd and is now well under way. Call that step one. In particular the top surface is being made both flat and level ready for the next step two, which will be to lower the wooden Curb Ring onto the top. There it will be bolted into place using the original eight studs that are still sticking out at the top of the wall. These studs (19mm diameter, 140mm protruding) are irregularly spaced, so Andy Selfe and Chairman John Hammer had to plot their positions very accurately so that when the Curb Ring is lowered, the studs fit neatly into the holes pre-drilled for them. Step three will be to assemble the Cap Ring, the Cap Frame (which will support the Windshaft) and the long and short stretchers. These are green-painted horizontal beams that are used to turn the Cap and sails into the wind. Once these four components are all bolted together, they will be lifted by mobile crane onto the top of the Mill. The Cap Ring, which rotates, fits neatly inside the fixed Curb Ring. Another crane lift will drop the Vertical Shaft inside the Mill, and more lifts will drop in the Brake Wheel and attach the long Tail Pole. After that, the Cap will get its thatch cover. This will keep the inside of the Mill dry, and enable all the interior “furniture” to be fitted.

The Brake Wheel & Lantern Pinion

Our last Update showed you the work being done by Mike Sutten on the Brake Wheel. Here are the finished wheel and Lantern Pinion, and also two of the four brake blocks (being made by Andy Selfe) that will fit on the outside edge of the wheel. For comparison, the 1995 brake wheel manufactured in the Netherlands is also shown, mounted on the Windshaft and with the brake blocks visible on the edge.

Curb Ring and Cap Ring

Here are the completed rings, with the Cap Ring able to turn inside the Curb Ring with a 3mm clearance between the two.

Cap Frame

Here is the nearly completed Cap Frame in Jon Stevens’ workshop. The green short stretcher is attached to the Frame in the foreground.

And here is a reminder of how the green long and short stretchers and the Tail Pole fit together. The miller can move the whole cap to face the wind by turning the capstan at the foot of the Tail Pole.

Windshaft

This is being cut to size by Kimon Mamacos of Sentinel Timbers in Hout Bay, but needs two months between each cut to dry out. We’ll tell you more with the next update.

For much more detailed information on the whole restoration process, please visit https://mostertsmillafterthefire.blogspot.com/?view=magazine compiled by Andy Selfe.

Yours sincerely – the Mostert’s Mill Restoration Team