Chop saw

1 . A chop saw power tool for cutting metal, the chop saw power tool comprising a saw base and a cutting head assembly,

the saw base comprising:

a support structure;

a workpiece support table comprising a workpiece support surface arranged to receive a workpiece to be cut in a cutting operation; and

rails connected to the workpiece support table,

the workpiece support table being rotatable in a plane of the workpiece support surface through a predetermined angular range relative to the support structure to select an angle of cut of the workpiece,

the cutting head assembly comprising:

a circular cutting blade arranged on the cutting head assembly and having an axis of rotation such that the circular cutting blade rotates within a cutting plane arranged in a fixed orientation perpendicular to the plane of the workpiece support surface,

wherein the cutting head assembly is pivotable relative to the saw base in a direction parallel to the cutting plane between a position where the cutting blade is remote from the workpiece and a position where the cutting blade is in contact with the workpiece,

wherein the cutting head assembly is slideably mounted on the rails and is linearly moveable relative to the workpiece support table to adjust a cut position of the cutting blade on a workpiece; and

wherein the chop saw power tool further comprises an interlock configured to secure the cutting head assembly in a plurality of discrete linearly-spaced fixed positions on the rails, relative to the workpiece support table prior to a cutting operation;

wherein the rails are connected to an end block at one end, and fixedly connected to the workpiece support table at an opposite end.

2 . A chop saw power tool according to claim 1 , wherein the cutting head is linearly movable along an axis parallel to the plane of the workpiece support surface.

3 . A chop saw power tool according to claim 1 , wherein the interlock comprises a first interlocking element fixed relative to one of the cutting head assembly and the workpiece support table and a second interlocking element fixed relative to the other of the cutting head assembly and the workpiece support table.

4 . A chop saw power tool according to claim 3 , wherein a plurality of second interlocking elements are provided, each second interlocking element corresponding to a discrete fixed position.

5 . A chop saw power tool according to claim 3 , wherein the first interlocking element comprises a rod and the second interlocking element comprises an aperture dimensioned and arranged to receive the rod.

6 . A chop saw power tool according to claim 5 , wherein the rod comprises a tapered distal end.

7 . A chop saw power tool according to claim 5 , wherein the rod is resiliently biased in a direction perpendicular to the direction of linear movement of the cutting head assembly in order to facilitate engagement with the aperture.

8 . A chop saw power tool according to claim 7 , wherein the rod comprises a coil spring arranged to surround the rod.

9 . A chop saw power tool according to claim 5 , wherein the rod further comprises a graspable handle arranged to move in a direction perpendicular to the direction of linear movement of the cutting head assembly order facilitate engagement with the aperture.

10 . A chop saw power tool according to claim 1 , wherein said rails are part of a rail arrangement which enables to linear movement of the cutting head assembly relative to the workpiece support table.

11 . A chop saw power tool according to claim 10 , wherein the rail arrangement is fixedly connected to the workpiece support table and the cutting head assembly is arranged to be movable linearly on the rail arrangement.

12 . A chop saw power tool according to claim 10 , wherein the rail arrangement is fixedly connected to the cutting head assembly and the cutting head assembly and rail arrangement are arranged to be movable linearly with respect to the workpiece support table.

13 . A chop saw power tool according to claim 10 , wherein the interlock is arranged to inter-engage with at least a part of the rail arrangement to secure the cutting head assembly in said one or more fixed positions relative to the workpiece support table prior to a cutting operation.

14 . A chop saw power tool according to claim 10 , wherein the rail arrangement is arranged below the plane of the workpiece support surface.

15 . A chop saw power tool according to claim 1 , wherein the cutting head assembly comprises a cutting head base arranged in a fixed rotational orientation relative to the saw base and a pivot connection to enable the remainder of the cutting head assembly to pivot with respect to the cutting head base, the pivot connection being offset from the cutting plane.

16 . A chop saw power tool according to claim 1 , further comprising an engagement lever operable to selectively provide a friction engagement of the cutting head assembly relative to the workpiece support table to assist in securing the cutting head assembly in one or more fixed linear positions prior to a cutting operation.

17 . A chop saw power tool according to claim 1 , further comprising a fence arranged to enable positioning and location of a workpiece, the fence being arranged in a fixed orientation with respect to the support structure of the saw base.

18 . A chop saw power tool according to claim 17 , wherein the fence extends across the workpiece support surface and comprises a gap located and arranged in the cutting plane of the cutting blade such that the cutting blade can pass therethrough during a cut.

19 . A method of using the chop saw power tool of claim 1 , the method comprising the steps of:

a) positioning a workpiece on the workpiece support surface and securing the workpiece;

b) linearly adjusting the cutting head assembly relative to the workpiece support table to adjust a cut position of the cutting blade on a workpiece;

c) securing, using the interlock, the cutting head assembly in a fixed position relative to the workpiece support table; and

d) performing a cutting operation.

20 . A method according to claim 19 , further comprising, prior to step d):

e) adjusting the mitre angle of the cutting head and workpiece support surface relative to the workpiece to select a desired angle of cut.

21 . A chop saw power tool according to claim 1 , wherein the end block is configured to support the rails.