Laminated Rubber Mallet: A Rubber-and-Canvas Head Locked on a Flared Handle by an Internal Rib (Whisler, 1924)

"When in position, the flared end 1a of the handle absolutely precludes the head from flying off when delivering blows and the rib and groove engagement prevents any inward displacement of the head."

Cut 17 plies of 3 mm natural rubber sheet 110 x 60 mm and 14 of cotton canvas the same size. Glue each paper circle from the template in the middle of its ply, numbered 1 to 17, and cut the hole round it with a sharp craft knife, holding the blade upright. Cut the same hole in a canvas ply for each of plies 1 to 14.

Brush contact cement on both faces to be joined, let it go touch-dry, and lay up the stack in order, ply 1 at the bottom: rubber, canvas, rubber, ... with the holes lined up over a 24 mm dowel through the middle, and plies 15, 16 and 17 rubber to rubber with no canvas. Press it between boards in clamps overnight. Trim the sides square with the knife and round the edges of the two striking faces slightly.

Turn a hardwood handle 330 mm long. At its head end turn the flared part 2a as long as plies 1 to 15 are thick, 32 mm at the end tapering to 24; then the groove 2b, 20 mm across and as long as plies 16 and 17; then the shoulder 2c, 28 mm, to bear on the head's inner face; then the grip, 28 mm tapering to 26 at its end, so it can pass the eye. Check each diameter with the caliper against the plies.

Warm the head for ten minutes in hot water and dry it. Push the grip end of the handle into the eye from the outer face (ply 1) and force it right through, the rib stretching over the grip and the shoulder, until the flared part seats in the eye and the rib snaps into the groove. Let it cool. Strike a board: the head must not move.

**Chauncy P. Whisler** of Kenmore, Ohio, assignor to The Miller Rubber Company, US 1,501,827, dated 15 July 1924, filed 2 January 1924. He claimed "a mallet having a head of elastic material provided with an outwardly flaring handle-receiving eye provided with an annular internal rib adjacent the inner face of the head, and a handle having an outwardly flared end engaging said flared eye, and an annular groove engaged by said annular rib", and "a stepped conical eye". His head was moulded of rubber and fibrous material, as in Maranville and Dabney's application; ours is laminated from rubber sheet and canvas with contact cement. He gives no sizes; every size here is ours.