Threaded-Stud Rubber-Head Hammer: Heads Screw Onto the Body's Own Studs and Lock the Handle's Nail In (Dicks, 1951)

"The nail when driven home obviously forms its own hole through the handle." "Obviously application of the head 15 retains the nail against loss if the same ever became somewhat loose in the handle."

From 38 mm steel round bar turn a body 80 mm long between end faces cut truly square, with a stud 14 16 mm across and 18 mm long standing out of each end; cut M16 threads on them with the die. Drill a 20 mm eye 11 through the middle, square to the axis, in a V-block, and flare its ends a little with a half-round file.

Scribe a line across one end face along the eye's direction. Centre-punch it 13 mm from the centre and drill 4.2 mm parallel to the axis, down into the eye, and counterbore the mouth 7 mm across and 4 mm deep for the nail's head.

For each head saw an M16 coupling nut to 25 mm and chamfer one end's thread 1 mm with a countersink: the socket 16 with its chamfered mouth 18. Cut 4 mm rubber discs 50 mm across: seven with a hole just round the nut and five solid. Bond them up round the nut with contact cement, the chamfered end flush with the head's inner face, and the solid discs at the striking face; clamp overnight and trim round.

Turn an ash handle 300 mm long to drive tight into the eye. Drive it home, then drive a 4 mm nail 23 down the bore through the handle until its head sits in the counterbore below the end face. Screw the rubber heads onto the studs until each bears hard on its end face.

**Byron R. Dicks** of Lebanon, Indiana, US 2,566,517, dated 4 September 1951, filed 25 March 1947. He claimed a cylindrical body "having flat faces at both ends disposed at true right angles to the axis", "threaded extensions integral with said body", detachable heads with threaded sockets "in face to face contact" with the body, a transverse handle opening, a longitudinal bore offset from the extensions through it, and "a safety pin" in the bore sealed in by the heads. His heads were turned from bar or made of any of the materials he lists, rubber among them; ours are rubber discs bonded round a threaded steel insert. He gives no sizes; every size here is ours.