Abstract: A bolt on drive assembly for a core drill which utilizes an improved high strength spoked reinforcer mounted beneath a disc. The disc and high strength spoke reinforcer are removably mounted on the tube by bolt fasteners. A drive connection is removably mounted and centrally located on a outer disc of the pair of discs. The drive connection is adapted to connect with a drive shaft to cause rotation of the tube. The system can also include a split in the disc when the high strength spoked reinforcer is not welded thereto thereby providing a means of water control. The high strength spoked reinforcer can be a separate piece that is bolted to the disc or can be integrally formed as one piece therewith.

Abstract: A heat reducing slot that is part of a saw blade that includes tips that will house carbide or other tips that are to be attached through a torch or induction. Heat reducing slots repeat for each tip on the perimeter of a blade that will be treated with high heat. For each tip, there is a general area defined near the seat and groove of the tip. In this general area a slot is inserted that has the effect of reducing the amount of heat needed to be applied to the blade for the attachment of carbide or other tips.

Abstract: An improved slot for a circular saw blade that reduces thermal cracking that occurs during the use of the blade. The slot extends from the peripheral edge of the blade in a vertical direction toward the center of the blade. It has an initial channel that takes a slight curve as it extends toward the center of the blade, but remains in a substantially vertical orientation until it terminates in a curve that is convex when viewed from the peripheral edge toward the center hole. The curve extends in both directions away from the channel portion. The first curve extends at a length that is longer than the length of the second curve. The curve does not complete a circle, but resembles a circle that has had been snipped at one point and one side hangs down below the other. Each curve terminates in an aperture.