Llangwyryfon Mill is a nineteenth century water-powered corn-mill containing a complete set of machinery and with its drying kiln intact.
The walls are of rubble masonry with large quoins. The roof of the mill and the kiln is of slate, and of the outbuildings is corrugated asbestos. The original openings of the mill have flat heads with rubble voussoirs; other openings have wooden lintels. The mill is a long range, two storeyed, with a single-storeyed stable and byre; there are later additions to the front and rear forming an 'office' and a kiln. The interior has wooden partitioning and the base for a (missing) oil engine. An original wide opening leads into the ground floor of the mill, the main ceiling beam of which is dated 1838. The machinery is mostly of cast iron: the main horizontal shaft, very large pit wheel, vertical shaft, wallower (with wooden teeth), spur wheel (with wooden teeth) and bolted-on contrate gear. This last drives a layshaft with a permanently-engaged wooden-toothed cog; the shaft carried a belt pulley for the chain-drive sack-hoist (belting from the shaft drove a shaft through the kiln to power a sawbench outside the building). There are two stone-nuts, and the chutes discharge into a meal-trough. There is a sack trap near the stair. The first floor of the mill is the stone-floor. There are two pairs of stones, the left hand stone a peak-stone in an octagonal box; the right-hand stone is a French burr stone in a circular box. Both have the stone-furniture complete. Between them is a moveable wooden crane with iron 'tongs' for lifting the stones for dressing: it is located in a hole in the beam and a hole by the stone. The sluice control is a lever operating through a small window by the left-hand stone. The hopper to the wire-machine is also on this floor. The trusses have halted apexes and bolted collars. The sack-hoist seems to post-date the addition of the office; the windlass is located between two beams, bolted to the purloin, between the trusses, and on the end is a large pulley chain driven from below.
Attached to the rear of the mill is the kiln. The gable is buttressed and the windows are shuttered. Inside, the firebox is of stone construction, with a ribbed brick four-way vault over. The kiln floor is complete, of tiles with a 'nine-hole diamond' pattern. The single truss (halted apex, bolted collar) is not smoke-blackened; there are vents in the ridge. The wheelpit is against the gable of the mill, at the end of a long (dry) millpond; it is stone-lined, and an offset in the mill wall might indicate an earlier launder level which could have driven two wheels. The 14 ft diameter overshot wheel (removed in 2002) has an iron rim, and wooden spokes and buckets: the iron hub has circular piercings.
RCAHMW, 15 July 2008.