Heavy cap timbers

As promised, a further update on the cap construction....

Having taken delivery of some rather hefty sections of oak, we are now in a position to start building up the main cap structure. First up, the two large beams which run front to back in the cap, the 'shears'. Here we see one of the shears in position, being cleaned up prior to being notched over the cap circle. Large timbers call for large planes!

Shear being cleaned up

With both shears cleaned up and notched into place, next came the transverse beams. The next photo is looking from the front of the cap towards the rear. So, we have, from front to back, the weather beam, sprattle beam and tail beam.

The weather beam and tail beam will support the front and rear ends, respectively, of the windshaft. The sprattle beam is effectively in the centre of the mill and will locate and support the top end of the main upright shaft.

The next two shots show some detail of how these beams are located in the shears.

Dovetail joint between weather beam and shear

Tenons at ends of weather beam and sprattle

The tenons on the sprattle (upside down in this shot) are cut to allow for wedging of the beam into position. This gives some scope for adjustment, so the upright shaft can run true. In contrast, the tail beam will be a direct fit. So, next job, morticing..........