2021 Restoration Update 3

– What has happened in the past month?

We mentioned in the last update that detailed plans, budgets and time frames would be needed for presentation to big corporate or state entities in order to raise the substantial sums needed for a professional restoration of the mill. This has been difficult for the wooden machinery components because some of them are really large and require specific types of wood. For example the windshaft, which carries the two pairs of sails, needs to be cut from a solid piece of timber at least 6,5 metres long to a square cross-section with sides 0,4 metre wide.

Andy Selfe, our Engineer, has found a standing sugargum tree (Eucalyptus cladocalyx) in Grabouw that was ring-barked two years ago and can be felled and shipped to Botrivier, where it will be sawn to the right size. The ends will be machined to a circular cross-section for fitting into granite bearing blocks, which allow the shaft and sails to rotate in the wind. After machining, the shaft has to be transported to Cape Town and lifted into position by crane. Sufficient old Bilinga (an African hardwood, Nauclea diderrichii) has been found in Cape Town for 24 smaller beams. There are another six beams ranging from 6 to 12,5 metres in length, but these can be scarfed (joined from shorter pieces) if necessary. Other timbers are needed for flooring, staircases etc.

The thatched cap together with a frame holding the windshaft and its sails can be rotated so that the sails face the wind. The whole rotating structure sits on two circular curb rings, one attached to the rotating bit and the other fixed to the top of the masonry wall of the Mill. The fixed one is 5,3 metres in diameter and has a square cross-section of 150 x 150 mm (6” x 6” in old units). The rotating one is similar but half as thick (and will be lubricated with lard so that it can slide on the fixed one). Both will be fabricated from sugargum.

As you can imagine, sourcing all the wood, costing it and the necessary transport, machining, jointing and assembly has been a big task for Andy, but it is now nearing completion. Plans and preliminary budgets for the masonry repairs have been completed. Meetings have been held with the Heritage Services Division of the National Department of Public Works & Infrastructure, Heritage Western Cape, and other interested parties. While some formalities regarding formal authorisation to proceed still remain, all of these discussions have been positive and encouraging.


A silver lining came our way with the Covid lockdown last year. The Zamani Project, associated with UCT (https://zamaniproject.org), was unable to visit the UNESCO World Heritage Sites at which it normally carries out detailed 3-D photogrammetric surveys using advanced laser equipment. So to practice their skills locally, last September they undertook a survey of Mostert’s Mill. We are now negotiating access to their results, which will assist greatly in determining some dimensions that are missing on the old 1935 plans that we have currently. (In 1995, some of the major wooden machinery was fabricated in the Netherlands).

Will our donations be acknowledged?

They are being whenever we can. But for a few of the EFTs we have no email address, and many of our Snapscan bank statements gave no payer’s name. We have modified our Snapscan code on this website to allow a donor’s name and/or email address to be included optionally. If you have made a donation and would like an acknowledgment, please email your name and the date & amount of the payment to our Treasurer at thorpex@iafrica.com. If you have friends or relatives overseas who would like to contribute, please refer them to www.GoFundMe.com/f/Mosterts-mill-restoration-fund.

Yours sincerely – the Mostert’s Mill Restoration Team

Andy’s update:

For the record, I’m busy constructing a drilling jig for the critical squareness and centrality of several holes; the top (for the pintle) and bottom of the vertical shaft and at least the front of the wind shaft, to insert a bar to turn it on.


The triangular tube is now welded to the edge of the steel angle. The angle will be fixed  (screwed or maybe strapped) to a corner of the square beam. Inside the tube another slides exactly and rigidly, and on the end of that is a bracket to which the drilling machine will be attached, all nice and square.


The bracket with the drilling machine attached will be slotted so that it can be set to drill on the precise centre.