Big Screw Nutcracker

This is a nutcracker design that is easy and satisfying to use. It will break open tough nuts with a smooth turning action and offers exquisite control. Inspired by the Over Engineered Nutcracker, this design is a combination of wood and metal construction. It can be held in one hand with the nut in place, while the other hand turns in the screw. It is very convenient and pleasant to use. This Instructable describes the main construction details involved in making this style of nutcracker.

You will need a big screw and a small chunk of strong wood. Clear maple was rescued from the firewood supply in the author's case. The nutcrackers shown here have big stainless steel 3/8-16 Allen head cap screws 3" long. The pressure pad for the end of the screw was made on a lathe from 3/4" diameter stainless steel bar stock, and 3/4" diameter brass rod for the threaded bushing.

The rectangular body of the nutcracker measures about 3-1/2" by 3" by 1-1/2". The nut pocket was hollowed out with a 2-1/8" diameter Forstner bit to a depth of 1-1/4"; this left a 1/4" thick wall behind the cavity adding needed strength to the cracker. The round shaped cracker started from a slightly wider chunk of wood to leave a slightly thicker wall around the nut pocket; after boring out the cavity, the blank was cut and sanded to the round outline. This shape fits the palm of the hand very nicely. The hole for the brass bushing is centered so that axis of the screw is in the center (i.e. front-to-back and side-to-side) of the nut pocket. The threaded bushings are shown in the photo.

The end of the screw was turned down to the minor thread diameter for a short length as can be seen in the photograph. These particular screws have very finely finished smooth and almost polished threads, which makes for smooth operation of the nutcracker. The pressure pad is turned from 303 stainless steel. The concave conical end helps capture and keep the nut in place as the screw is turned. The other end is shouldered and bored to fit the screw end; upon final assembly it is secured to the screw with retaining compound.

The handle for cranking the screw is a 2" length of 1" diameter birch dowel bored to accept the head of the screw. The ends are rounded and sanded smooth for a comfortable grip. The handle is secured to the screw with a generous application of clear epoxy.

A good finish for items used with food is a mixture of beeswax and pure mineral oil. In use, this compound is slightly warmed until very soft and almost liquid, then wiped on and rubbed in. After a time, the piece is buffed off with a soft cloth. If the wood is sanded nice and smooth, this Beeswax finish leaves a pleasant velvety feel to the piece.

The threaded bushing is held in place with a light coat of epoxy. Note that the flange of the bushing is on the inside of the cavity so that it takes on the heavy thrust of nutcracking. After turning in the screw halfway, the pressure pad is permanently attached with a strong retaining compound such as Loctite 609. After that, there is no taking the nutcracker apart !

The author actually made four like these and gave three as Christmas gifts - with a supply of nuts to crack.

The rectangular nutcracker is my favorite !