Abstract: A repositionable abrasive disc mounting assembly comprises a backup pad and a clamp assembly. The backup pad has a rotational axis of use and a major surface with projections extending outwardly therefrom. The backup pad further comprises an inwardly facing centrally disposed first fastening member, and also an outwardly facing centrally disposed second fastening member. The clamp assembly comprises inner and outer clamp members for securing an abrasive disc. The inner clamp member comprises an inwardly facing centrally disposed third fastening member adapted to repositionably engage the second fastening member in a discrete number of rotational orientations. The inner clamp member further comprises an outwardly facing centrally disposed fourth fastening member. The outer clamp member comprises an inwardly facing centrally disposed fifth fastening member adapted to securely engage the fourth fastening member. A method of abrading a workpiece using the repositionable abrasive disc is also disclosed.

Abstract: A spike retainer which may be forcibly driven through an aperture in a tie plate into a wood cross tie includes an upper lip for engaging a flanged base of a rail supported by the tie plate. A movable wedge attached to the spike retainer is forced between the cross tie and the tie plate when a spike is forcibly inserted into the spike retainer, thereby clamping the tie plate and the flanged base of the rail between the upper lip and the movable wedge. The spike retainer is initially inserted into a pre-drilled hole in the cross tie by means of an insertion tool having a channel which permits the spike retainer to be forcibly inserted into the hole without engaging the movable wedge.

Abstract: A system is disclosed for converting solar radiation into electricity and for storing energy generated in excess of demand. The system includes a large circular collector fabricated from modular elements. The collector is combined with a concentrator and boiler for producing steam. The steam produced is used to drive an electrical generator and a hydraulic pump. When system demand is less than the capacity of the generator, the excess energy is used to drive the pump. The pump transports water from a low level reservoir to an elevated reservoir, thereby storing potential energy. Later, when demand increases, water from the elevated reservoir is used to drive a second electrical generator. The circular collector is mounted on tracking apparatus which automatically aims the collector to focus on the sun and receive maximum solar radiation on its surface.

Abstract: A railroad spike retainer is disclosed which may be driven into a railroad tie together with the spike it retains. The retainer exerts a retention force both against the spike to prevent its regression from the retainer and also against the tie to prevent the regression of the retainer itself from the tie.