Tool inserts in the form of PCD (polycrystalline diamond) tips with a carbide backing are sold to saw blade manufacturers for use in the woodworking industry. Such manufacturers have automatic brazing machines for brazing the tips into pockets on a saw blade. The tips or saw teeth need to be oriented correctly-usually with the PCD facing down and a chamfered end of the carbide going forward for this brazing operation. Feeding of PCD saw teeth correctly oriented in a reliable manner to the brazing machine is a major headache for saw blade manufacturers.

SUMMARY OF THE INVENTION According to the present invention, a unit comprises: a plurality of tool inserts, each insert defining a working region and being adapted to be secured to a tool to present that region with a predetermined orientation; and a body defining a plurality of discrete zones, each zone having an insert located therein such that the orientation of the working portion of each insert in the zones is the same.

In one preferred form of the invention, the body is elongate in form and the zones are defined along the length of the body. The body will typically take the form of a tape.

The zones may be pockets or recesses in the body into which the inserts are placed.

The invention has particular application to tool inserts for saw blades which comprise a PCD layer bonded to a carbide backing, the PCD layer providing the working region.

According to another aspect of the invention, there is provided a collection of tool inserts as described above in combination with apparatus such as brazing apparatus for securing the inserts to a tool.

DESCRIPTION OF THE DRAWING The drawing illustrates a perspective view of an embodiment of the invention.

DESCRIPTION OF AN EMBODIMENT An embodiment of the invention will now be described with reference to the accompanying drawing. Referring to this drawing, a length of tape 10 has a plurality of pockets 12 formed along its length. The tape is coiled on to spindle 14. Located in each pocket 12 is a saw blade tip 18. Each saw blade tip 18 has a carbide backing 20 to which is bonded a PCD layer 22. The PCD layer is formed with a leading cutting edge 24. The carbide backing 20 has a chamfered edge 26.

A saw blade tip 18 is located in each pocket 12 such that the cutting edge 24 of each tip 18 is located at the forward end 28 of the pocket and facing down and into the pocket as illustrated.

In use, the spindle 14 (which will generally form part of a reel) will be suitably mounted to a saw blade manufacturer's brazing machine. When it is necessary to braze tips to a saw blade, the tape will be moved forward one pocket. As the tape moves forward one pocket, a cover tape 30 is simultaneously peeled back from the pocket, exposing one correctly oriented saw blade tip. This is then picked up by a brazing machine attachment and placed into the feeding track of the brazing machine ready for brazing. When the tip 18 has been brazed into position, another pocket is moved forward and the process repeated.