WO2018015753A1

WO2018015753A1 - Cross joint milling machine

Info

Publication number: WO2018015753A1
Application number: PCT/GB2017/052130
Authority: WO
Inventors: Michael Derham; Mark FORTUNE
Original assignee: Mighton Products Limited
Priority date: 2016-07-20
Filing date: 2017-07-19
Publication date: 2018-01-25
Also published as: GB2552355A; GB201612597D0

Abstract

The cross joint millingmachine (10) is arranged to cut frame members for use with glazing products and in particular for window/door glazing panels. The frame members comprise Georgian bars, astragal bars and other glazing bars/elements. The cross joint milling machine (10) is arranged to cut a first bevel section (22) and a second bevel section (24) within a frame member (20) which acts as a work piece in the machine arrangement. The cross joint milling machine (10) is also arranged to cut a groove (26) extending between the first bevel section (22) and the second bevel section (24). The interconnecting groove (26) is either cut on the rear face (32) of the frame member (20) or the front face (30) of the frame member (20) and partially extends through the depth of the frame member (20). In particular, this groove cut may extend half way through the depth of the frame member (20). Accordingly, in one pair of intersecting frame members (20, 40), a first frame member (20) has a groove (26) cut in to the front face (30) whilst the second frame member (40) has a groove (46) in to the rear face (50).The cross joint milling machine (10) is portable and can be easily transported by a user and hence used on site at an assembly location. Accordingly, this portability enables a user to quickly and easily and accurately produce crossjoints in frame members at the assembly location.

Description

Cross Joint Milling Machine

FIELD OF THE INVENTION The present invention relates to a cross joint milling machine and a method of forming a cross joint in intersecting frame members. In particular, the present invention relates to a cross joint milling machine for producing timber (window/door) frame members and a method of forming a cross joint in intersecting window/door frame members.

BACKGROUND TO THE INVENTION

Some styles of windows and doors include frame members which extend across the glass to form a grid or lattice. These frame members divide the window/door into smaller framed areas for decorative purposes. Such frame members include Georgian bars, astragal bars and other similar glazing bars/elements.

The frame members extend horizontally and vertically across a pane of glass of the window/door and intersect with each other. At these intersections a cross joint is formed. These cross joints typically comprise corresponding shaped or bevelled sections which are linked with an intersecting groove. These recesses are formed on both frame members. The joining sections correlate with each other on the two members such that the two frame members can be neatly interlocked and secured to each other. The aim is to provide a seamless joint to increase the aesthetics and decorative look of the window/door.

The bevelled sections and the groove are typically created on a cross joint milling machine. These machines are designed for the mass production of the frame members such that the frame members are then distributed ready for immediate assembly. Alternatively, an assembler/fitter will need to manually cut or mill the two bevelled sections and the groove at specific positions on the frame members in order to create the cross joints. Windows/doors formed from such mass produced frame members will only be provided in specific sizes and configurations. This limits the choice and the available sizes and configurations may not be optimal or the required size or configuration. The individual creation of the cross joints by the assembler/fitter is time consuming since these are generally created using different machines and or with different set ups for each cut. In addition, the formation of these individual cross joints is relatively skilled and/or results in cross joints which are not close fitting and may not be aesthetically pleasing.

Several separate cutting/milling machines can be used to produce the individual bevels and grooves. Alternatively, a single machine may be provided for mass producing the frame members in which a work piece is moved and manipulated between the cuts within the machine. In such a machine, the movement and manipulation of the work piece between the various cutting/milling stages can introduce errors. Accordingly, in these systems there is a potential opportunity for the work piece to be unintentionally moved and/or misaligned between the various cutting and milling stages. It is an aim of the present invention to overcome at least one problem associated with the prior art whether referred to herein or otherwise.

SUMMARY OF THE INVENTION According to a first aspect of the present invention there is provided a cross joint milling machine comprising:

clamping means;

a first shaped cutting head for cutting a first bevel in a work piece;

a second shaped cutting head for cutting a second bevel in a work piece; a groove cutting head, for cutting a groove between the first bevel and the second bevel in the work piece;

wherein the clamping means is arranged to clamp the work piece in a clamped position and whilst in the clamped position:

the first cutting head and the second cutting head are simultaneously movable to cut the first bevel and the second bevel in the work piece; and

the groove cutting head is movable to cut a groove in the work piece.

Preferably the groove cutting head is movable to cut a groove between the first bevel and the second bevel.

Preferably the first cutting head and the second cutting head are initially simultaneously movable to cut the first bevel and the second bevel in the work piece and then the groove cutting head is subsequently movable to cut a groove in the work piece.

Preferably the first cutting head and the second cutting head are automatically movable between the rest position and the cutting position. Preferably the first cutting head and the second cutting head are automatically movable by pneumatic and/or electrical means (motors/actuators) between the rest position and the cutting position. Preferably the first cutting head and the second cutting head are manually movable between the rest position and the cutting position.

Preferably the first cutting head and the second cutting head are mounted to a mounting member.

Preferably the mounting member is movable and more preferably automatically movable between the rest position and the cutting position. Preferably the mounting member is automatically movable by pneumatic and/or electrical means (motors/actuators) between the rest position and the cutting position.

Preferably the mounting member is secured to an operating handle. Preferably the handle is arranged to be gripped by a user and operated in order to move the first cutting head and the second cutting head.

Preferably the handle is provided on a lever. Preferably the handle is provided on a pivotally mounted lever. Preferably the pivoting movement of the lever produces translational movement of the first cutting head and the second cutting head.

Preferably a separation distance between the first cutting head and the second cutting head is fixed (and maintained) during the movement of the first cutting head and the second cutting head between the rest position and the cutting position.

Preferably the first cutting head comprises a truncated conically shaped cutting head. Preferably the second cutting head comprises a truncated conically shaped cutting head.

Preferably the first cutting head is driven by a first motor and the second cutting head is driven by a second motor.

Preferably the groove cutting head comprises a rotatable cutting shaft and more preferably comprises a router cutter or a router cutting head/bit.

Preferably the groove cutting head comprises a planar rotatable cutting disc. Preferably a cutting edge extends radially outwardly from the cutting disc. Preferably the groove cutting head is mounted on a support member. Preferably the groove cutting head is mounted on the mounting member. The mounting member may comprise a mounting frame on which the first cutting head, the second cutting head and the groove cutting head are all mounted. The mounting frame may be movable to cause the first cutting head and the second cutting head to cut the work piece. The groove cutting head may be movable on (and/or relative to) the mounting frame in order for the groove cutting head to cut the work piece. Preferably the mounting frame is initially moved vertically relative to the work piece and the groove cutting head is then moved relative to the mounting frame.

Preferably the machine comprises a positional element (or indicator) to indicate a depth of groove for the groove cutting head to cut. The positional element or indicator may stop the vertical (downward) movement of the mounting frame to position the groove cutting head at the correct depth relative to the work piece. The positional element or indicator may be adjustable to enable the depth of the cut to be adjusted. The positional element or indicator may have a plurality of pre- set depths set. The positional element or indicator may comprise a first setting for a first depth, a second setting for a second cut and a third setting for a third depth and a fourth setting for a fourth depth and so forth. The positional element or indicator may comprise a rotatable wheel (capstan) with a plurality of abutment members projecting radially outwardly therefrom. Each abutment member may extend radially outwardly to a different extent to correspond with different cut depths. The abutment member is arranged to abut and prevent (arrest) the mounting frame moving downwardly and this thereby sets the cut depth. The rotatable wheel is rotatable to enable a user to orientate the wheel to provide and/or register a correct abutment member with a part of the mounting frame.

Preferably the support member is connected to a handle portion which is arranged, in use, to be gripped by a user. Preferably the handle is arranged to be moved translationally in order to translationally move the groove cutting head between a rest position and a cutting position.

Preferably the handle is pulled outwardly from a base portion of the cross joint milling machine between the rest position and the cutting position. Preferably the handle is retracted and/or pushed inwardly into a base portion of the cross joint milling machine between the cutting position and the rest position.

Preferably the groove cutting head is driven by a groove cutting motor. Preferably the groove cutting motor is triggered by the movement of the groove cutting handle. The grove cutting motor may only be triggered as the groove cutting head approaches the work piece and the groove cutting motor may be powered off as the groove cutting head returns to the rest position. The cross joint milling machine comprises guide mean to guide the work piece. The guide means may guide movement of the work piece between a position for creating a first cross joint and a position for creating a second cross joint. Preferably the guide means enables the work piece to be moved longitudinally between the first position and the second position.

Preferably the clamping means clamps the work piece in the guide.

Preferably the guide comprises a cutting template section. Preferably the cutting template section provides recess portions which correspond with the cuts to be formed in the work piece. Preferably the cutting template section supports the work piece directly adjacent to the cuts to be formed. Preferably the cutting template section prevents (or inhibits or reduces) the formation of splinters (or rough edges) particularly at the finish of a cut. Preferably the cutting template section provides a support cutting surface to provide clean edges for the cuts.

Preferably the guide means includes an index member. Preferably the index member sets the position of the work piece for the first cross joint cutting position and/or the second and/or subsequent cross joint cutting positions. The clamping means may be arranged to clamp the work piece within the cross joint milling machine whilst all three cutting heads are operated and then the clamping means is arranged to be released to enable the work piece to be removed or repositioned within the guide means. Preferably the clamping means comprises a first clamp member and a second clamp member and the clamp members may be arranged to clamp the work piece on either side of the portion of the work piece to be cut. The first clamp member and the second clamp member may be urged downwardly on to an upper surface of the work piece in order to clamp the work piece within the guide.

The clamp means may comprise pneumatic clamp means.

Preferably the work piece is arranged in use to be clamped in a lateral position across a base of the cross joint milling machine. Preferably the first cutting head and the second cutting head are arranged to be moved vertically downwardly to the cutting position and to be moved vertically upwardly to the rest position. Preferably the groove cutting head is arranged to move forwardly from a rear position in a base of the cross joint milling machine and to move rearwardly to a rest position. Preferably the groove cutting head moves perpendicularly relative to a longitudinal axis of the work piece.

Preferably the groove cutting head projects upwardly by a predetermined (and set amount) from a support surface of the cross joint milling machine. Preferably the projecting height can be adjusted which may thereby be used with work pieces of different thicknesses.

The guide may be interchangeable. The interchangeable guide may enable work pieces of different dimension to be cut within the machine. The machine may comprise an outer housing. The outer housing may be arranged to encompass and/or encase and/or surround the cutting heads during the operation of the cutting heads. The outer housing may comprise an encasing cover which is (manually) moved into position prior to the cutting heads being activated. The clamp(s) may be manually activated once the housing is closed and the work piece is correctly positioned within the guide. In use, a user may manually move the housing into position and then (activate the clamp and then) activate the cutting operation. The cutting operation may be automatic with the movement of the three cutting heads being controlled by a control system. The outer housing may have a first aperture on one lateral side and a second aperture on a second lateral side to enable an elongate work piece to project therethrough. According to a second aspect of the present invention there is provided a method of forming a cross joint in a work piece comprising:

clamping the work piece in a cross joint milling machine;

wherein the cross joint milling machine comprises:

a first shaped cutting head for cutting a first bevel in a work piece;

wherein the method further comprises, whilst the work piece is in the clamped position:

simultaneously moving the first cutting head and the second cutting head to cut the first bevel and the second bevel in the work piece; and

moving the groove cutting head to cut a groove in the work piece.

Preferably the method comprises moving the groove cutting head between the first bevel and the second bevel.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described by way of example only with reference to the drawings that follow, in which:

Figure 1 is a perspective view of a preferred embodiment of a cross joint milling machine. Figure 2 is a schematic view of a preferred embodiment of a first and second bevel cutting head and a work piece. Figure 3 is a schematic view of a guide and indexing mechanism of a preferred embodiment of a cross joint milling machine.

Figure 4 is a front perspective view of a first and second frame member including the cross cuts.

Figure 5 is a rear perspective view of a first and second frame member including the cross cuts. Figure 6 is a front perspective view of the first and second frame members partially engaged with each other.

Figure 7 is a schematic view of another preferred embodiment of a cross joint milling machine.

Figure 8 is a schematic view of another preferred embodiment of a part of a cross joint milling machine.

Figure 9 is a schematic view of an adjustment indicator device of another preferred embodiment of a cross joint milling machine.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in Figure 1 , a cross joint milling machine 10 comprises a base 12 with feet 14 in order for the cross joint milling machine 10 to be placed on a work surface. The cross joint milling machine 10 is portable and can be easily transported by a user and hence used on site at an assembly location. Accordingly, this portability enables a user to quickly and easily and accurately produce cross joints in frame members at the assembly location.

As mentioned above, the cross joint milling machine 10 is arranged to cut frame members for use with glazing products and in particular for window/door glazing panels. The frame members comprise Georgian bars, astragal bars and other glazing bars/elements. These frame members are secured vertically and horizontally across a glazing panel to divide the glazing area into smaller framed areas. For example, the glazing area may be divided into smaller rectangular framed areas. Accordingly, the frame members must intersect with each other as they extend across the glazed area from one outer (upper, lower, side/lateral) frame to an opposite (upper, lower, side/lateral) frame member. The cross joint milling machine 10 is arranged to cut the intersecting joint in order for the dissecting frame members to fit together whilst providing a relatively seamless joint.

The cross joint milling machine 10 is arranged to cut a first bevel section 22 and a second bevel section 24 within a frame member 20 which acts as a work piece in the machine arrangement. The cross joint milling machine 10 is also arranged to cut a groove 26 extending between the first bevel section 22 and the second bevel section 24. The interconnecting groove 26 is either cut on the rear face 32 of the frame member 20 or the front face 30 of the frame member 20 and partially extends through the depth of the frame member 20. In particular, this groove cut may extend half way through the depth of the frame member 20. Accordingly, in one pair of intersecting frame members 20, 40, a first frame member 20 has a groove 26 cut in to the front face 30 whilst the second frame member 40 has a groove 46 in to the rear face 51 .

The frame members 20, 40 are arranged to intersect perpendicularly such that the bevel sections 22, 24, 42, 44 provide four opposing faces which all correspond with each other and the groove sections 26, 46 also form an interlock in the centre of the cross joint. This enables the two frame members 20, 40 to lie flush with each other in the final assembly and the bevel faces all fit snugly with each other to provide a seamless join which is aesthetically pleasing.

The cross joint milling machine 10 includes a first milling head 60 and a second milling head 70 which for example (as shown) may comprise a first router bit and a second router bit which are advantageous over saw blades. Each milling head 60, 70 has an individual (electric) motor 62, 72 in order to power and rotate the respective milling head 60, 70. The first milling head 60 and the second milling head 70 are mounted on a mounting frame 80 such that the milling heads 60, 70 are simultaneously moved. In a preferred embodiment shown in Figure 1 , the mounting frame 80 is secured to a lever 82 which is manually operable.

The lever 82 is pivotally connected to support members 84, 85 extending upwardly from the base 12. In addition, the lever 82 is connected to a gas strut 86 in order to aid the movement of the lever 82. The geometry of the pivotal lever 82 and the mounting frame 80 is arranged to move the milling heads 60, 70 vertically downwardly through the work piece. The position and separation distance of the two milling heads 60, 70 can be set maintained whilst numerous work pieces are cut.

The cross joint milling machine 10 also comprises a groove cutting head 90 comprising a cutting plate which can be moved translationally across the base 12 of the cross joint milling machine 10. The groove cutting head 90 comprises a disc 91 which locates within a guide slot 92 and can be moved manually along the slot 92 by a handle 94. The depth of the groove 26, 46 to be cut is controlled by the distance to which the groove cutting disc 91 projects above the support surface for the work piece. This projecting distance can be set and then retained for cutting numerous work pieces. The handle 94 is pulled outwardly from the base 12 in order to move the groove cutting disc 91 across the work piece and to thereby cut the groove 26, 46 between the two bevelled sections 22, 24, 42, 44. The groove cutting disc 91 and guide slot 92 are arranged to coincide with the centres of the bevel cutting heads 60, 70 and hence the bevel cuts 22, 24, 42, 44 are formed within the work piece.

The cross joint milling machine 10 also comprises a guide 100 into which the work piece is retained. This guide 100 enables the work piece to be correctly positioned within the cross joint milling machine 10 in order for both bevels 22, 24, 42, 44 to be cut and also for the intersecting groove 26, 46 to be cut. The guide 100 also includes clamping means to clamp the work piece firmly within the cross joint milling machine 10 whilst all three cuts 22, 24, 26, 42, 44, 46 are formed.

The clamping means comprises a first clamping member (plate) and a second clamping member (plate) which are urged downwardly on to the top of the work piece. The clamping plates 130 are arranged to locate either side of the portion of the work piece which is to be cut. The clamping plates 130 are urged downwardly by pneumatic means (a pneumatic cylinder). The clamping means are manually activated once the user has correctly position the work piece within the machine. Similarly, the clamping means are deactivated by the user once the cuts have been made. In addition, the guide means 100 may also comprise an indexing member 102 which may be set in order for the location of the cross joint on the work piece to be set along the longitudinal length of the work piece. This indexing stop 102 may also enable subsequent cross joints to be formed equidistantly along the longitudinal length of the work piece.

In use, the work piece comprising the frame member 20, 40 is located within the guide means 100 and is longitudinally positioned using the index abutment 102 in order to set the first longitudinal position of the cross joint. In this secured position, the first bevel section 22, 42 and the second bevel section 24, 44 are formed.

In the clamped position, a user manually moves the lever 82 downwardly which simultaneously moves the first milling head 60 and the second milling head 70 relative to the work piece. The two milling heads 60, 70 thereby form opposing bevel cuts 22, 24, 42, 44 in the opposing lateral sides of the work piece. The lever 82 is returned to an upward position to move the milling heads 60, 70 away from the work piece. A user then pulls the handle 94 outwardly from the cross joint milling machine 10 which moves the groove cutting head 90 laterally across the work piece. This groove cutting head 90 will cut a groove 26, 46 partially through the work piece extending between the first bevel section 22, 42 and the second bevel section 24, 44. The groove cutting head 90 does not cut to the full depth of the work piece but may cut a groove 26, 46 to a depth of approximately half of the depth of the work piece.

As mentioned above, subsequent intersecting work pieces may be cut in the opposite orientation such that the grooves 26, 46 extend through the front face 30 rather than the rear face 32. The handle 94 is returned to the inner position to move the groove cutting head 90 back to the starting position. The clamping means can be subsequently released now that all three cuts 22, 24, 26, 42, 44, 46 have been formed within the work piece. If required, the work piece can be longitudinally moved in order for further cross joints to be formed along the length of the frame member. In particular, the initial cross joint may be moved to the index stop 102 in order for the second subsequent cross joint to be formed. Similarly, the second formed cross joint can then be moved to the index stop 102 in order for the third cross joint to be formed and so on and so forth.

As mentioned above, the intersecting work pieces must be orientated with a first frame member 20 having a groove 26 on the rear face 32 and the second intersecting frame member 40 having the groove 46 on the rear face 52. Accordingly, subsequent frame members may be cut with either the front face 30, 50 or the rear face 32, 52 facing downwardly towards the base of the cross joint milling machine 10.

Another preferred embodiment of the cross joint milling machine is shown ion Figures 7 - 9. This embodiment essentially functions as described above. However, the in this embodiment the groove cutting head 90 comprises a router bit which cuts the groove in the upper facing surface of the work piece. As above, the first cutting head 60 and the second cutting head 70 are mounted on a mounting frame 80. In addition, the groove cutting head is also mounted on this mounting frame 80. Accordingly, all three cutting heads are arranged to move simultaneously downwardly in an initial cutting phase. From the starting position, the frame member 40 moves between the two cutting heads 60, 70 in order for the two bevels to be created. In this movement the work piece moves to the relative position of the work piece 40a shown by the dashed lines in Figure 7. At this stage, the groove cutting head is triggered to move transversely across the work piece in order to form the groove between the two bevel sections. In this phase, the groove cutting head 90 (and motor 93) moves to the position of the groove cutting head 90a shown in dashed lines in Figure 7.

The movement of the cutting heads 60, 70, 90 are all automatically controlled by a control system. Once the cutting operation is activated, the cutting heads 60, 70, 90 are all arranged to move automatically and in sequence until the milling/cutting is complete.

The movement of the cutting heads/mounting frame 80 is powered by a pneumatic system. In other embodiments an electrical system may be used. The motors 62, 72, 93 for the cutting heads may be electrically powered.

The work piece is held within a guide 100. The guide 100 includes a template section 101 immediately around the work piece where the cuts will be formed. This template 101 includes cut-out or shaped sections which will correspond closely with the cuts to be formed in the work piece. In particular, these shaped sections just allow the cutting heads 60, 70, 90 to pass therethrough with minimal clearance. These shaped sections are particularly important in the formation of the two bevel sections. This helps the work piece to be secured at position immediately adjacent to the cuts and to form a scissor type action to remove any burrs/splinters etc. Accordingly, this template section 101 helps to provide clean cuts without any abrasions. The machine includes a positioning element 1 10 or limiting element to set the depth of the groove to be cut. In particular, this positioning element 1 10 arrests the downward movement of the mounting frame 80. For example, a part of the mounting frame 80/cutting head arrangement 62, 72 may be arranged to move downwardly until the positioning element 1 10 is abutted. This abutment prevents the further downward movement of the mounting frame 80 and signals for the translation movement of the groove cutting head 90 to be performed. At this stage, the groove cutting head 90 moves horizontally across the work piece to form the groove.

The positioning element is adjustable to enable the depth of the groove to be adjusted and controlled. As shown in Figure 9, the positioning element 1 10 comprises a rotating wheel member (capstan) 1 1 1 including a number of abutment members 1 12, 1 14, 1 16, 1 18. The wheel 1 1 1 is manually rotated until the appropriate abutment member 1 12, 1 14, 1 16, 1 18 is directly in opposition to the mounting frame 80 / motor 62 which will be moved downwards to abut the positioning element 1 10.

The abutment members 1 12, 1 14, 1 16, 1 18 all extend radially outwardly from the wheel 1 1 1 by a pre-set amount. This embodiment provides four pre-set groove depths. However, the abutment members 1 12, 1 14, 1 16, 1 18 may include threaded shafts which can be screwed into or out of the wheel 1 1 1 in order to provide further adjustment of the groove depth. The wheel 1 1 1 may have an indexing mechanism to direct an abutment member 1 12, 1 14, 1 16, 1 18 to be correctly aligned in a vertical direction and not slightly off vertical.

The machine 10 includes an outer housing 120 which is manually pivoted between a closed position and an open position. This outer housing 120 cover provides protection from the cutting heads 60, 70, 90 and also helps to collect and prevent the distribution of any dust and debris. The machine 10 may include a failsafe mechanism to prevent the operation of the cutting heads 60, 70, 90 whilst the cover 120 is open or partially open. The cover 120 may include an aperture 122 on both lateral sides walls to enable an elongate work piece to pass therethrough. These are arranged to align with the guide 100. In addition at least a portion of the guide 100 may locate outside this cover 120 to help support the work piece.

The guide may be interchangeable to enable a guide of different dimensions to be used to enable the machine 10 to be used in cutting frame members of different dimensions. In particular, the guide is essentially a channel member and therefore a channel member of a different width could be used. Similarly, an interchangeable template section may also be required.

In addition, the guide may provide a measuring rule or indicator along one surface to enable a user to measure the projection and position of the work piece within the guide.

Claims

1 . A cross joint milling machine comprising:

clamping means;

a first shaped cutting head for cutting a first bevel in a work piece;

the groove cutting head is movable to cut a groove in the work piece.

2. A cross joint milling machine according to Claim 1 in which the groove cutting head is movable to cut a groove between the first bevel and the second bevel.

3. A cross joint milling machine according to Claim 1 or Claim 2 in which the first cutting head and the second cutting head are initially simultaneously movable to cut the first bevel and the second bevel in the work piece and then the groove cutting head is subsequently movable to cut a groove in the work piece.

4. A cross joint milling machine according to any preceding claim in which the first cutting head and the second cutting head are automatically movable between the rest position and the cutting position by pneumatic means.

5. A cross joint milling machine according to any preceding claim in which the first cutting head and the second cutting head are mounted to a mounting member.

6. A cross joint milling machine according to Claim 5 in which the mounting member is movable between the rest position and the cutting position.

7. A cross joint milling machine according to any preceding claim in which a separation distance between the first cutting head and the second cutting head is fixed and maintained during the movement of the first cutting head and the second cutting head between the rest position and the cutting position.

8. A cross joint milling machine according to any preceding claim in which the first cutting head comprises a truncated conically shaped cutting head, the second cutting head comprises a truncated conically shaped cutting head and the groove cutting head comprises a rotatable cutting shaft comprising a router cutting bit.

9. A cross joint milling machine according to any preceding claim in which the groove cutting head is mounted on a mounting member and the mounting member comprises a mounting frame on which the first cutting head, the second cutting head and the groove cutting head are all mounted.

10. A cross joint milling machine according to Claim 9 in which the mounting frame is movable to cause the first cutting head and the second cutting head to cut the work piece and the groove cutting head may be movable on the mounting frame in order for the groove cutting head to cut the work piece and wherein the mounting frame is initially moved vertically relative to the work piece and the groove cutting head is then moved relative to the mounting frame.

1 1 . A cross joint milling machine according to any preceding claim in which the machine comprises a positioning element to indicate a depth of groove for the groove cutting head to cut.

12. A cross joint milling machine according to Claim 1 1 in which the positioning element stops the vertical downward movement of the mounting frame to position the groove cutting head at the correct depth relative to the work piece.

13. A cross joint milling machine according to Claim 1 1 or Claim 12 in which the positioning element is adjustable to enable the depth of the groove cut to be adjusted.

14. A cross joint milling machine according to Claim 13 in which the positioning element has a plurality of pre-set depths set.

15. A cross joint milling machine according to any preceding claim in which the cross joint milling machine comprises guide mean to guide the work piece and the clamping means clamps the work piece in the guide.

16. A cross joint milling machine according to any preceding claim in which the guide comprises a cutting template section providing recess portions which correspond with the cuts to be formed in the work piece.

17. A cross joint milling machine according to any preceding claim in which the clamping means is arranged to clamp the work piece within the cross joint milling machine whilst all three cutting heads are operated and then the clamping means is arranged to be released to enable the work piece to be removed or repositioned within the guide means.

18. A cross joint milling machine according to any preceding claim in which the clamping means comprises a first clamp member and a second clamp member and the clamp members are arranged to clamp the work piece on either side of the portion of the work piece to be cut.

19. A cross joint milling machine according to Claim 18 in which the first clamp member and the second clamp member are urged downwardly on to an upper surface of the work piece in order to clamp the work piece within the guide.

20. A cross joint milling machine according to any preceding claim in which the clamp means comprises pneumatic clamp means.

21 . A cross joint milling machine according to any preceding claim in which the work piece is arranged in use to be clamped in a lateral position across a base of the cross joint milling machine and the first cutting head and the second cutting head are arranged to be moved vertically downwardly to the cutting position and to be moved vertically upwardly to the rest position and the groove cutting head is arranged to move forwardly from a rear position in a base of the cross joint milling machine and to move rearwardly to a rest position and in which the groove cutting head moves perpendicularly relative to a longitudinal axis of the work piece.

22. A cross joint milling machine according to any preceding claim in which the machine comprises an outer housing and in which the outer housing is arranged to encompass the cutting heads during the operation of the cutting heads.

23. A method of forming a cross joint in a work piece comprising:

clamping the work piece in a cross joint milling machine;

wherein the cross joint milling machine comprises:

a first shaped cutting head for cutting a first bevel in a work piece;

moving the groove cutting head to cut a groove in the work piece.

24. A cross joint milling machine substantially as herein described with reference to, and as shown in, any of the accompanying figures.

25. A method of forming a cross joint in a work piece substantially as herein described with reference to, and as shown in, any of the accompanying figures.