The Screw-Casing Lemon Squeezer: A Plunger Driven Down by a Screw

"B is a screw which passes through the upper portion of the casing A, and carries at its lower end a plunger, C, which turns loosely thereon, and is of the form seen in Fig. 1, its diameter being considerably less than that of the interior of the casing A." "When the plunger C is forced down the lemon assumes the shape seen in Fig. 2, the upper half being forced into the lower half, thus extracting every particle of juice and avoiding all waste."

**Casing.** Cut 90 mm of 50 mm PVC pipe and push a 50 mm PVC end cap onto each end. Drill a 6 mm hole in the centre of the bottom cap: the nozzle. Drill two 5 mm holes through the top cap's skirt and the pipe, opposite each other, and hold the cap on with two M5 bolts and nuts so it comes off to load the lemon. **Screw.** Drill 10.5 mm through the centre of the top cap and epoxy an M10 nut over the hole inside it. Screw 20 cm of M10 threaded rod through. Drill 10 mm across the middle of 12 cm of hardwood dowel and lock it on the rod's top between two nuts: the T-handle. **Plunger.** Drill a 10.5 mm hole in the centre of a 32 mm PVC end cap and fit it, open side up, on the rod's bottom end between a washer and two nuts tightened against each other, loose enough to turn. **Test.** Weigh a lemon, cut off both ends, put it in the casing and bolt the cap on. Over the measuring jug, turn the handle until no more juice comes; hook the spring scale to the handle's end once to read your push. Weigh the juice. Squeeze a second lemon of the same weight by hand and weigh its juice.

**Valentine Fogerty** of Boston, Massachusetts, assigned US 52,928 to Corns. Callaghan of Boston and James Birmingham of Roxbury; it is dated 27 February 1866. His casing was "of iron or other suitable material", the lower end of the lemon "previously cut off or perforated", and the handle could be turned a few times for a little juice and again later. **Honest limits.** PVC pipe, caps, an M10 rod and a locked pair of nuts stand in for Fogerty's iron casing and screw, and bolts for his screwed halves. The notebook uses a square-thread efficiency, a little high for a V-thread; its hand force, handle radius and friction are examples. Your juice weights are the result.