A tool bit for a surface working machine, the tool bit comprising: a tool body for connection to a tool carrier blade of the surface working machine, the tool body comprising a neck at one end for connection to the tool carrier blade and an insert cavity at an opposite end for accommodating a tool insert; and a tool insert for insertion into the tool body of the tool bit, the tool insert comprising: a cylindrical stem for engagement with the tool body, the cylindrical stem having a free base end opposite a body end, wherein the cylindrical stem comprises a first bevel around the circumference of the stem at the base end and a second bevel around the circumference of the stem at the body end, the first and second bevels (18, 20) for engaging the tool body and distributing load substantially evenly around the tool body; a tapered body in connection with the cylindrical stem at the body end thereof, the tapered body having an angle of taper (a) and having a minimum base diameter equal to or greater than an outside diameter of the tool body thereby protecting the tool body when inserted; and a tip having a convex dome shape of radius and connected for engaging a surface to be worked, the tip comprising an outer surface free of edges and adjacent the tapered body opposite the cylindrical stem. a tool body for connection to a tool carrier blade of the surface working machine, the tool body comprising a neck at one end for connection to the tool carrier blade and an insert cavity at an opposite end for accommodating a tool insert; and a tool insert for insertion into the tool body of the tool bit, the tool insert comprising: a cylindrical stem for engagement with the tool body, the cylindrical stem having a free base end opposite a body end, wherein the cylindrical stem comprises a first bevel around the circumference of the stem at the base end and a second bevel around the circumference of the stem at the body end, the first and second bevels (18, 20) for engaging the tool body and distributing load substantially evenly around the tool body; a tapered body in connection with the cylindrical stem at the body end thereof, the tapered body having an angle of taper (a) and having a minimum base diameter equal to or greater than an outside diameter of the tool body thereby protecting the tool body when inserted; and a tip having a convex dome shape of radius and connected for engaging a surface to be worked, the tip comprising an outer surface free of edges and adjacent the tapered body opposite the cylindrical stem. a cylindrical stem for engagement with the tool body, the cylindrical stem having a free base end opposite a body end, wherein the cylindrical stem comprises a first bevel around the circumference of the stem at the base end and a second bevel around the circumference of the stem at the body end, the first and second bevels (18, 20) for engaging the tool body and distributing load substantially evenly around the tool body; a tapered body in connection with the cylindrical stem at the body end thereof, the tapered body having an angle of taper (a) and having a minimum base diameter equal to or greater than an outside diameter of the tool body thereby protecting the tool body when inserted; and a tip having a convex dome shape of radius and connected for engaging a surface to be worked, the tip comprising an outer surface free of edges and adjacent the tapered body opposite the cylindrical stem.