The Ribbon-Cutting Can Opener: A Square Knife That Rolls Up a Strip and Leaves Smooth Edges

A thin blade drawn through tin leaves ragged, sharp edges on the lid and on the can. Isaac N. Arment of Dayton, Washington Territory, received US 327,983, dated 13 October 1885, for improvements on his 1880 opener, consisting in "the removal of a narrow ribbon or strip of the metal by means of a knife having a broad or rectangular cutting-edge; and it consists, further, in the method of rolling up into small compass the narrow ribbon or strip removed by the knife." The knife's flat face, about a sixteenth of an inch wide and inclined at about thirty degrees, "cuts out a small portion of the tin the same width with itself, and curls the said narrow portion into a solid roll and down into the can, and leaves both edges" "smooth and straight, as though cut by a pair of shears." A clamping plate and thumb screw lock the head block, and a second knife on the bar's side cuts square cans and round cans just below the rim. This rung works out how small the ribbon rolls up, then makes the broad-edged knife on a clamped head block, and compares its edges with those of the 1880 blade.