Abstract: A high solidity impeller has a number of equally spaced blades, each formed from a sheet that is bent to a continuous cylindrical curve along a roll axis that lags (in the rotation direction) the radius at which the blade is attached to the shaft. The blade also is pitched by rotation around the radius, i.e., the leading edge is raised in the flow direction and the trailing edge is lowered. The roll axis preferably lags the radius by 45.degree.. This arrangement provides a good approximation of a true hydrofoil and results in an excellent reconciliation between interests of material and manufacturing cost vs. pumping efficiency. The blades can be formed by rolling asymmetrically shaped contours cut from a flat sheet. A base member and preferably a connecting arm couple each blade to the shaft. The base member abuts the rolled contour along surfaces referenced to the roll axis, which surfaces can be used as a reference for rolling.