Abstract: A knife sharpener includes guide structure for accommodating thick blades of a knife. The guide structure includes a fixed guide surface having a convex portion to match a concave shape of the blade and a spring guide surface preferably has a convex portion to press against a hollow ground portion of the blade.

Abstract: A manual sharpener includes at least one pre-sharpening stage having interdigitating comb-like abrasive sharpening structure. The sharpener also includes a finishing stage having a pair of abrasive surfaced truncated conical disks as its sharpening structure. The disks are mounted on a rotatable shaft with the small ends of the disks in contact with each other.

Abstract: A manual sharpener includes at least one pre-sharpening stage having interdigitating comb-like abrasive sharpening structure. The sharpener also includes a finishing stage having a pair of abrasive surfaced truncated conical disks as its sharpening structure. The disks are mounted on a rotatable shaft with the small ends of the disks in contact with each other.

Abstract: A knife sharpener includes guide structure for accommodating thick blades of a knife. The guide structure includes a fixed guide surface having a convex portion to match a concave shape of the blade and a spring guide surface preferably has a convex portion to press against a hollow ground portion of the blade.

Abstract: An electric sharpener for sharpening ceramic blades includes at least one stage. The stage is a finishing station having a sharpening member in the form of a disc which comprises a rigid support having a flexible abrasive matrix which both sharpens and polishes the facet of the ceramic blade. The sharpener may include a pre-sharpening stage for metal blades and a further pre-sharpening stage for ceramic blades. The sharpener also includes a removable guide.

Abstract: An electric sharpener for sharpening ceramic blades includes at least one stage. The stage is a finishing station having a sharpening member in the form of a disc which comprises a rigid support having a flexible abrasive matrix which both sharpens and polishes the facet of the ceramic blade. The sharpener may include a pre-sharpening stage for metal blades and a further pre-sharpening stage for ceramic blades. The sharpener also includes a removable guide.

Abstract: The problems associated with rotating a wing sail around a stayed rig mast; changing the airfoil shape of a wing sail on different tacks; and reefing a wing sail may be solved by using an A-frame mast with port and starboard mast extrusions for supporting two asymmetrical wing sails.

Abstract: A combination sharpener assembly which is particularly useful for fishermen, includes an electrically powered knife sharpener. A manually operated scissors sharpener is mounted in the recess of the housing for the knife sharpener. A hook sharpener is detachably mounted in a compartment in the housing of the knife sharpener. The motor for the knife sharpener is mounted in a sealed inner housing and can be selectively operated under either direct current or alternating current.

Abstract: A combination sharpener assembly which is particularly useful for fishermen, includes an electrically powered knife sharpener. A manually operated scissors sharpener is mounted in the recess of the housing for the knife sharpener. A hook sharpener is detachably mounted in a compartment in the housing of the knife sharpener. The motor for the knife sharpener is mounted in a sealed inner housing and can be selectively operated under either direct current or alternating current.

Abstract: An electrically powered knife sharpener for ceramic (or other brittle, crystalline or amorphous media which could be used for blades) knives includes at least one pre-sharpening stage with a sharpening member(s) and includes a final stage with a sharpening member(s). There are one or more motor driven shafts on which the abrasive surfaced sharpening members, such as disks, are mounted. Guide structure is provided to guide the knife for aligning and positioning the knife facet precisely at a defined location on the abrasive surface of each rotating sharpening member. The pre-sharpening stage sharpening member(s) moves in a first direction. The final stage sharpening member(s) moves in a second direction which differs from the first direction.

Abstract: A knife edge enhancing apparatus includes a support having a support surface and knife blade clamping structure mounted to the support and located above the support surface. An object having a knife edge modifying surface which could be abrasive or non-abrasive is mounted to a holder which is freely slidable on the support surface so that the object surface can be manually moved into contact with a knife edge facet. At least one of the clamping structure and the object surface is angularly adjustable to control the angle of contact of the object surface with the knife edge facet.