Twybil

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A twybil is a hand tool used in green woodworking to clear out mortises quickly. It combines chopping and levering in one tool. It looks like a T-shaped double-edged axe with long blades and a short handle, but it actually comes from a large double-ended chisel with an added side handle for control. The two working ends are different: one is an axe-like edge parallel to the handle, and the other is a crosswise edge for prying and levering.

Mortises are rectangular holes that take a tenon in joints like mortise-and-tenon. Traditionally, ends are marked with a drill, then the twybil is used to remove the waste between the marks. The axe edge splits the wood, and the levering edge lifts out the split block. The short handle lets you flip the tool and use each end quickly, making the work faster and safer than swapping between a chisel and a lever.

A twybil should not be used as a regular axe; its long, straight blades aren’t made for swinging. There are two main forms: a large framing twybil with a straight edge, and a smaller curved or hooked version where the edge curves under or inside. The levering end always has a single bevel like a chisel.

Twybils are usually iron with steel edges welded on, though modern ones may be all steel and sometimes use recycled springs. The handle is a short wooden socket on the side. They’re relatively rare today and can be expensive; a few makers still produce them.

Related tools include the mortise chisel, used for chopping across the grain and shaping the mortise ends, and slicks, which finish and square up the mortise. Apprentices may use all three, but skilled framers choose the right tool for each step to work faster and protect edges.