GB2077185A - Saw guide apparatus - Google Patents

Abstract

The apparatus is arranged to be placed upon a workpiece (W), having bearer means that define location planes for mutually transverse faces of the workpiece. The bearer means comprise at least two relatively adjustable members (4, 6 or 6, 54) and a saw guide (20) is provided on a first bearer member (6) to define a forwardly facing saw guide plane 30. A further one (4 or 54) of the bearer members is adjustable to provide a workpiece location plane rearwards of the saw guide means at an adjustable distance from the saw guide plane. The saw guide plane is defined by a planar element (28) that can be mounted in the saw guide means in different positions relative to the bearer means. The saw blade is held against the guide face (30) of the planar element by a U-form resilient member (38) that is adjustable vertically of said guide face. The saw guide element (28) may be provided with an oblique front face for use in cutting dovetail slots and pins. <IMAGE>

Description

SPECIFICATION Saw guide apparatus This invention relates to saw guide apparatus for use with handsaws of various kinds.

Guide apparatus for sawing operations is known in many different forms. The conventional mitre box, for example, is often employed for preparing mitre joints of frames but is limited in its applications and also in the size of workpiece that it will accept. It is still widely used because of its robust nature, but even when attempts have been made to make more versatile forms of apparatus in which a workpiece can be placed for sawing, the incorporation of further facilities can make them cumbersome, and they remain extremely limited as regards the maximum size of workpiece that can be accommodated.

Other saw guide apparatus has been developed that is adapted to be placed upon the workpiece, this resulting in a more compact form of apparatus, and also generally allowing it to be used with larger sizes of work. However, such apparatus often has only limited capabilities, such as the saw guides of UK Patents 620650 and 904254. Thus, although these saw guides can be placed against the side faces of a workpiece to guide the saw at specific angles to those side faces, they do not provide any means of controllably locating the position of the saw longitudinally of said side faces.

There is known (UK patent 1 502 596) a relatively robust form of saw guide apparatus that is adapted to be supported on a workpiece which is capable of a number of different functions. This comprises bearer means that are adapted to be placed on a workpiece with a forwardly facing guide face behind which the bearer means extend to engage longitudinal side faces of the workpiece, and a transverse location device can provide a datum at an adjustable distance in front of the guide face, but this is of limited practical value as a means of locating the saw guide plane at desired positions longitudinally of said side faces. Also, while it is able to be supported upon relatively large workpieces, it can only make a limited depth of cut.Moreover, the setting arrangements for making oblique cuts are complicated and, indeed, it is not possible to use the apparatus practically for making 45" mitre cuts.

This last form of apparatus, like other known apparatus that is adapted to be placed upon a workpiece, is primarily useful for making cuts across the width of an elongate workpiece and cannot be readily adapted to making cuts longitudinally of the workpiece.

Even in an example of known apparatus, such as UK patent 620650, in which a rotatable saw guide is employed that can be disposed longitudinally to the bearer means by which the apparatus is supported on the workpiece, there is no practical value to be derived from this as there is no way of adjusting the spacing of the saw guide relative to the workpiece side faces.

According to one aspect of the present invention, there is provided saw guide apparatus comprising bearer means arranged to be placed upon a workpiece and having faces defining location planes for mutually transverse faces of the workpiece, and saw guide means on said bearer means providing a forwardly facing guide face defining the orientation of a saw guide plane relative to said workpiece faces, the bearer means comprising at least two members that are adjustably secured together, the saw guide means being secured to or forming a part of a first of the bearer members, a second of said bearer members being adjustably securable to said first member to provide a location plane rearwards of the saw guide means at an adjustable distance from the saw guide plane.

By providing longitudinal displacement between the bearer members they can alternatively be used for location and/or gauging the longitudinal position of a saw cut made transversely of the workpiece. Moreover, by arranging that the members are relatively rotatable to adjust the angular orientation of said one member relative to the saw guide plane and are relatively displaceable in their rotated positions, it is possible to provide for a mode of use in which the apparatus can guide a saw cut parallel to a planar face of a workpiece over any length. Additionally or alternatively the saw guide means may be pivotably secured to the first bearer member for angular adjustment relative to said mutually transverse faces of the workpiece.

Preferably, said first bearer member has a bottom face capable of defining a top face location plane perpendicular to a workpiece location plane defined by a side face of another member of the bearer means. That is to say a bottom face is planar, or is otherwise able to form a stable locating face in a plane perpendicular to a second locating face provided by a further member of the bearer means. Such an arrangement can be adapted for use either right-handed or left-handed.

According to another aspect of the invention, there is provided saw guide apparatus comprising bearer means carrying saw guide means and being adapted to be placed upon a workpiece to locate the apparatus against the workpiece for said saw guide means to define the orientation of a saw guide plane relative to the workpiece, said saw guide means comprising a planar element mounted on a carrier member to present an upwardly extending saw guide face, the element being provided with location means for mounting it in the saw guide means in different positions relative to the bearer means.

In this manner, a range of adjustment is provided that does not require re-location of the bearer means in a manner that may make it more difficult to hold the apparatus securely against the workpiece while a saw cut is being made.

Thus, it is possible to provide an element securable to the carrier member in alternative angular orientations at 90 to each other about an axis transverse to the saw guide face, said saw guide face being directed obliquely to a longitudinal axis of the bearer means and thereby providing a saw guide plane inclined at the same angle either in the vertical direction or transverse to said vertical direction, whereby the apparatus can be utilised for cutting dovetail pins and sockets in workpieces forming the respective members of dovetail corner joints.

According to a further aspect of the invention, there is provided saw guide apparatus comprising bearer means carrying saw guide means and being adapted to be placed upon a workpiece to locate the apparatus against the workpiece for said saw guide means to define the orientation of a saw guide plane relative to the workpiece, said saw guide means comprising a planar element mounted on a carrier member to present an upwardly extending saw guide face, and the saw guide means is provided with a U-form resilient member for urging the saw blade against the saw guide face, said member being mounted in the saw guide means to be adjustable vertically of the saw guide face.

The invention will be described in more detail by way of example with reference to the accompanying drawings, wherein: Figure 1 illustrates a first embodiment of saw guide apparatus according to the invention, Figure la is a transverse section of the aparatus in Fig. 1.

Figures ib and ic are front and plan views of the supporting bracket of the saw guide means in the apparatus of Fig. 1, Figures 2 and 3 show the apparatus of Fig.

1 in two different modes of use, Figure 4 illustrates a further form of apparatus according to the invention, Figure 5 illustrates the apparatus of Fig. 4 in another mode of use, Figure 6 illustrates the apparatus of Fig. 4 with modified saw guide means, Figures 7 and 8 are side and plan views illustrating a further modification of the apparatus of the preceding figures, Figures 9 and 10 are rear and side views of a saw guide element for apparatus according to the invention, Figure 11 illustrates a further modified form of apparatus according to the invention, and Figure 12 illustrates the apparatus of Figs.

1 to 3 in a further mode of use.

Referring mainly to Figs. 1 and 1 a to 1 c of the drawings, the apparatus there comprises a two-member bearing means 2, this having a lower angle-section member 4 and an upper shallow channel-section member 6. The members are secured together by a clamping screw 8 that passes through a longitudinal slot 10 in the member 6 to engage a tapped hole 1 2 in the lower member. The slot 10 is enlarged at its rear end to allow the members to be separated without removing the screw.

As can be seen in Fig. 1a the screw can be used to hold the members parallel, with the flanges 14 of the channel-section member seating in longitudinal recesses 1 6 in the top face of the member 4.

Beyond the forward end of the slot the upper member 6 projects past the lower member and has a nut and screw fixing 1 8 for a saw guide device 20. The guide device comprises a right-angle bracket 22, with a horizontal limb 24 held by the screw and nut fixing and a vertical limb 26 on which a saw guide element 28 is secured by a screw 32 having its head recessed into the element to be clear of a planar front guide face 30 of the element that defines a saw guide plane. The vertical limb 26 has front flanges 26a that seat in a recess 34 in the rear face of the element 28 to locate the bottom edge of that element horizontally. The screw 32 passes through an elongate slot 26b in the limb 26 allowing the element to be adjusted upwardly and downwardly on the limb before it is secured by a nut on the screw.

A guide spring 38 provided to hold a saw blade (not shown) against the guide face 30.

The guide spring is formed by stainless steel or aluminium alloy strip in the form of an inverted narrow "U" with a bifurcated rear leg 40 received in the slot between the limb 26 and the element 28. The spring 38 is adjustable upwardly and downwardly and is secured by a further screw 33, recessed into the front face 30, like the screw 32. A nut 33a retaining the screw 33 is disposed in the top recess 27 in the limb 26 and the spring is therefore not clamped directly to the limb 26 although the sides of the flanges 26awill prevent the spring element rocking about the screw 33. The manner of attachment of the spring allows its height to be adjusted relative to the saw guide element and it can also be inserted into its slot from above or from below. The forward leg 42 of the spring overlies the front guide face 30 and the free end of the forward leg is formed in a shallow 'V" to bear resiliently against the guide face.

Fig. 1 illustrates the use of the apparatus to make a saw cut in an elongate workpiece W at 909 to its main faces. The user holds the bearer means with one hand against the workpiece so that horizontal and vertical limbs 4a, 4b of the angle-section member 4 bears firmly against the abutting workpiece top and side faces respectively, and with the blade of a handsaw (not shown) retained against the saw guide face by the spring 38, the 90 saw cut is made.

Angular adjustment is possible about the axes of the screw and nut fixings of the saw guide device 20 to the upper bearer member 6 and of the upper bearer member 6 to the lower bearer member 4. Preferably, for both such adjustments location means are provided whereby specific angular orientations can be obtained. Thus, additional grooves can be formed in the upper face of the member 4 to receive the flanges 1 4 of the upper bearer member, and Fig. 1 shows a pair of such grooves 48 directed at right-angles to the angle member. These can be used, in the manner illustrated in Fig. 2, to locate the two bearer members at right-angles to each other, so that the vertical limb 4b of the angle member locates against an edge of a workpiece W rearwards of the saw guide means, while the bottom face of the upper member 6 locates on the top face of the workpiece.This arrangement is particularly suitable for making saw cuts in relatively wide workpieces, such as boards.

The bottom edge of the saw guide element 28 can also engage the workpiece top face to assist in supporting the apparatus stably. In the different modes of use shown in Figs. 1 and 2 the element 28 must be at different levels relative to the bearer means to do this, but the elongation of the slot 26b permits the necessary adjustment.

By means of further slots similar to the slots 48 but set obliquely in the lower member 4, it is possible to adjust the two bearer members to make oblique cuts in the workpiece. However, it is more appropriate, when there is a need for making such oblique cuts in elongate workpieces, e.g. for framing, to make use of the angular adjustability of the saw guide device. In the forward end of the upper bearer member 6 beyond the slot there is a longitudinal rib 50 that can seat in alternative slots 24a in the underside of the horizontal limb 24 of the bracket 22 and Fig. 3 illustrates how the bracket 22 can be rotated through 45 on the upper member 6 to be located obliquely by the rib 50. The slots illustrated allow adjustment through 45 and 90 in both directions, but other angles can be provided.

Further modes of operation are possible using bearer means of greater depth than those illustrated in Figs. 1 to 3. Fig. 4 illustrates an example, in which the same upper bearer member 6 is employed with a lower bearer member 54 that now takes the form of an I-section strip bent to a right-angled "S": a screw and nut fixing 56 is provided, with a plurality of alternative receiving holes 58 in the lower member horizontal limbs. In this embodiment the lower Storm member 54 the workpiece W, and the I-section of the lower member is disposed symmetrically between the flanges 14 of the upper channel-section member 6 so that the bottom face of one of those flanges locates on the top face of the workpiece.

It will be clear that, as compared with Fig.

1, the increased depth of the S-section member gives substantially greater stability when the apparatus is held against a workpiece, which may be particularly important when making saw cuts on members with a relatively narrow top face, such as the moulding illustrated in Fig. 4. In fact, because the lower member there extends below the workpiece, for firmer location it can be used as a bench stop or can be gripped in a vice on which the workpiece rests. The location of the apparatus may be assisted by the provision of transverse projections such as pins 60 on the forward limb of the S-forrn member having their bottom face in the same plane as the bottom faces of the upper member channel flanges.

The form of the lower member in this modified apparatus provides for other modes of use of the apparatus, as will now be described. In the mode shown in Fig. 4, the forward limb 62 projects upwards to above the level of the upper bearer member 6, and thus has its rear face directly opposed to the saw guide face 30. By setting the spacing between the saw guide face and the forward limb, and then aligning the rear face of that limb to a datum on the workpiece, e.g. the end face of a workpiece or a previous saw cut, a saw cut can be made at a required distance from that datum. The displaceability of the spring 38 allows it to be moved clear of the saw guide face to facilitate setting the spacing.If the workpiece is to have a halved joint with another elongate member, simply by gripping that other member lightly between the forward limb and the guide face before tightening the screw 56, this distance can be set to its width. Fig. 4 also illustrates how the relatively deep lower bearer member may depend below a workpiece and be used as a bench stop, or may have its bottom portions held in a vice.

The overall longitudinal and vertical extent of the lower member 54 is sufficient for it to provide support for the apparatus against the workpiece in either of these directions. Fig. 5 shows the S-form member reversed as compared with Fig. 4, so that top face of a workpiece W is engaged by the upper bearer member 6 and/or the lower edge of the saw guide element, and the workpiece side face by end face 65 of the shorter end limb 64 of the lower member 54, now located rearwards of the saw guide plane. With the apparatus held by clamping the end limb 64 against the workpiece side face this is suitable for making a saw cut vertically or nearly vertically in the end face of an elongate member in a position spaced forwards from the locating side face.

In the example of Fig. 5, if the workpiece W is to be one part of a halved joint, the position of the vertical saw cut in the other part of the joint can be gauged using the vertical cut face in the workpiece W after the waste has been removed at one side of the first saw cut. To do this the spacing between the limb 64 and the saw guide face 30 is set at the distance between the first saw cut and the opposite face of the workpiece to that with which the limb 64 is shown in contact in Fig. 5.

When sawing wide workpieces, it will be understood that the mode of operation shown in Fig. 2 may be employed using the modified form of the apparatus of Figs. 4 and 5, with the S-form member 54 turned at right-angles to the upper member. Slots can be provided in either or both horizontal limbs of the S-form member, like the grooves 48 in the bearer member 4, to give a positive angular setting.

For wide boards it is also possible to remove the lower bearer member of either of the forms of apparatus described above. If the saw guide device is then turned through 90 , so that the saw guide face 30 is directed parallel to the upper bearer member, and that member is abutted against the side face of a batten or like straight-edge clamped to the workpiece, the saw guide face will then define a plane parallel to the abutment face and the apparatus can be used to make a saw cut at a predetermined and fixed spacing from that face.

Referring again to Fig. 4, this also illustrates a modification of the saw guide device in that a guide element 28a is provided with grooves in its rear face for two spaced guide springs 38, both vertically adjustable and reversible (as will be described below). Further more, to increase wear resistance a facing sheet 30a, e.g. of a plastics laminate, can be adhered to the front face of the saw guide element in this and other embodiments. If required, interchangeable saw guide elements may be provided for specialised functions, e.g. for hacksaws for coping saws, for tile cutters etc.

Referring to Fig. 6, another modification of the saw guide device is shown in which a guide face element 70 is provided having an oblique front face. The rear face is still located vertically by the bracket but the element has a tapered thickness so that the front face is inclined at a small angle to allow it to be used for cutting the pins and slots of dovetail joints. Preferably an inclination of 8" is pro vided, a conventional angle for dovetails. The guide element is shown in position for cutting the sides of dovetail pins that must have their faces inclined to the longitudinal (vertical axis from the joint end face of the workpiece W.

To cut the opposite sides of the dovetail pins the element 70 is turned through 180 . To cut the sides of the dovetail slots on a simi larly located second workpiece the element is turned through 90 and 270 . Mutually transverse grooves 34 allow the guide spring 38 to be inserted from the uppermost edge of the guide element 70 as it is turned to each new position: preferably in each case the bottoms of the spring grooves are at a uniform distance from the guide face.

Fig. 6 shows a further possible modification of the apparatus to incorporate two saw guide devices at opposite ends of the bearer means.

As illustrated the upper bearer member 72, otherwise similar to the member 6, is cranked at its rear end to form an integral saw guide bracket 74 on which the additional saw guide element 28 is mounted, with a guide spring 38 if required. This may be of particular advantage when it is required to make saw cuts at two different settings (as in the case of dovetail pins and slots) and it is then possible to preserve the settings while all the cuts are being made. It will be understood that this second saw guide device may be mounted on a pivotable bracket also if required. It is alternatively possible to form the saw guide bracket in the previously described embodiments as an integral part of the upper bearer member. Although some modes of adjustment may not be possible this will be a more economical construction.

Figs. 7 and 8 illustrate an alternative modification for use in cutting dovetail joints. In this case a modified lower bearer member 76 is of inverted U-form with dependent limbs 78a, 78b one of which is perpendicular to the horizontal intermediate section and the other of which is at an angle of 8" to the vertical.

The limb 78a can be used in the same way as the limb 64 (Fig. 5). The limb 78b can be set against a side face of a workpiece W, as illustrated in Fig. 7, to locate the saw guide plane at 8" to that side face. The figure shows one side of a dovetail pin being cut and the opposite inclined other side is cut after reversing the workpiece W to locate against the opposite side face.

For cutting the dovetail slots as shown in plan in Fig. 8 the lower member has two pairs of grooves 80a, 80b oppositely inclined at 8" to the longitudinal axis, so that the saw guide face can be located at an oblique position to the vertical side face of the workpiece W for the mating part of the joint.

Figs. 9 and 10 illustrate another saw guide element 82 that can be assembled in different positions for different uses. The guide element has an elongate rectangular form with a pattern of projections on its rear face formed by ribs running parallel to its side edges and interrupted by similarly directed recesses.

Along its longer dimension the rear face has a single central pair of interrupted ribs 84 while along its shorter dimensions the rear face has three similar pairs of interrupted ribs 86 sym metrically spaced. A series of three apertures 88 are formed through the element at the intersections of the centre-lines of the pairs of ribs, each with hexagonal sockets 90 for holding a hexagonal screw head. These are the sockets for the fixing screw that attaches the element 82 to a supporting bracket 22, with the flanges 26a of the bracket embracing a pair of ribs 84 or 86, as indicated in Fig. 10.

Using the ribs 86 the guide element can be mounted with either of its longer edges uppermost, because alternative apertures with hexagon sockets 92a are provided above and below each socket 90 for the guide spring attaching screw 33. Using the ribs 84 the guide element can be mounted with either of its shorter edges uppermost, the lowermost of the sockets 88 being used in either instance for the fixing screw 32 and the adjacent socket 92b above it holding the guide spring attaching screw 33.All four edges of the guide elements can thus be used as a lowermost edge, where wear from the saw teeth is most likely to occur, and because of the three pairs of ribs 86 the guide element can also be placed asymetrically relative to the mounting bracket, e.g., so that the major part of its width extends over the workpiece for better stability of the apparatus and increased clearance for the saw handle.

As a further modification, by disposing a pair of ribs such as the ribs 86 adjacent an edge of the guide element, it can be mounted on its bracket 20 without that edge extending beyond the width of the bearer upper member. Referring to Fig. 4, if the guide element 30 does not project past the location plane formed by the side edges of the S-form member 54 it can be mounted in a position in which it depends below the upper bearer member and thus below the top face of the workpiece. The element can thus guide the saw blade through a greater depth of cut.

It may be noted here that although for firmer guidance the lower part of a saw blade should be kept in contact with the guide element as it cuts through the workpiece, this may introduce a very slight inaccuracy in the saw cut, due to the fact that the saw blade will be held slightly out of the vertical (as represented by the saw guide face) due to the set of its teeth. To ensure that the face of the saw blade is in planar contact with the saw guide face, the guide element above the workpiece should have a recessed lower edge, as illustrated at 92 in Fig. 7, so that the laterally projecting tips of the teeth do not contact the saw guide element. Generally, however, it is unnecessary to try to avoid this source of minor inaccuracy.

The saw guide device may incorporate means acting as a depth stop to limit the depth of saw cut. For example, if used with a backsaw, the saw guide element may be so adjustable in height so that the saw movement downwards is limited by engagement of the spine of the saw with the upper edge of the element. In some modes of use the guide spring 38 can be used as a depth stop by reversing it from the illustrated position so that it is upwardly open. Near their junction the two vertical limbs of the spring are joined by a screw bolt 94 (Fig. 1) that forms an axle for a hard plastics roller 96 and when the saw teeth engage the roller further downwards movement of the saw is prevented. The roller rotates freely and therefore little or no damage is caused to it or the saw teeth.The screw bolt 94 can help to draw the two limbs of the guide spring together and so be used to adjust the spring pressure with which a saw blade is held against the guide element.

In its inverted orientation, when sawing relatively small section workpieces, it may also be possible to locate a guide spring (or a single bifurcated bar) behind the workpiece as a supporting leg for the apparatus resting on the surface on which the workpiece is placed.

Fig. 11 shows a further modified apparatus according to the invention. The upper bearer member 6 and saw guide device 20 are as described before but a longitudinally and rotatably adjustable intermediate box frame member 102, is clamped to the upper member by the screw 8, and to a planar bottom element 1 02a of the member 1 02 a lower L-shaped member is secured to be longitudinally adjustable. Location against a workpiece top face is provided by the upper bearer member 6, and side face location by the side edges 1 02b of the intermediate member 102 together with the lower member 104 if this is present. The upper member is held in longitudinal alignment with the intermediate member by grooves (as in the previously described embodiments).Auxiliary grooves 110 are illustrated for receiving the channel section flanges of the upper member to locate the upper and intermediate members at right angles to each other and there may of course be similar pairs of grooves for other angular orientations. The lower member 104 is slidable longitudinally on the intermediate member and is secured by a further clamping screw 11 2. It is therefore adjustable independently of the relative positions of the upper and intermediate members, and its upright terminal limb 1 04a can be employed in the same way as the limb 62 shown in Fig. 4. With the lower member 104 removed, the forward end face 1 02c of the intermediate member can be employed in the same way as the shorter vertical limb 64 shown in Fig. 5.

With the lower member removed, if the intermediate member is inverted, as shown in broken lines in Fig. 11, its lugs 108 depend a short distance below the upper member to function as a side location for the workpiece.

In this configuration the apparatus can be used for, e.g. a workpiece held in a bench vice, where there is not enough clearance for the lugs of the intermediate member.

It is a feature of all the apparatus described that it is possible to assemble and adjust it to use it either right-handed or left-handed. In the example of Fig. 11 by re-assembling the bearer members with the upper member 6 reversed, but on the same side of the lugs 108 as illustrated, and with the lower member 104 also reversed, the saw guide means 20 and the vertical limb 104a will face in the opposite direction to that shown in the drawing.

It is also possible to use the apparatus described in the preceding examples as a drilling jig, by replacing the saw guide device with a drill plate containing one or more drill bushes. Fig. 1 2 illustrated this modification applied to the apparatus of Figs. 1 to 3. The lower bearer member 4 has been turned at right angles to the upper member 6 and the saw guide bracket has been replaced by a horizontal drill plate 1 22. Replaceable drill bushes 1 24 in prepared holes in the plate permit a series of holes to be drilled at a constant distance from the edge of the workpiece abutted by the flange of the lower member. The drill plate illustrated is itself formed by a saw guide element, identical to the previously described element 28 except for the added drill bush holes.

It will be understood that in all instances in which the bearer means comprises a member having an upright limb disposed forwardly beyond the saw guide plane, means can be provided for attaching a selector head, as is described in UK patent specification 1 502 596, for assisting the location of a saw cut relative to an existing cut or end face as described in that earlier patent specification.

While the saw guide elements have been illustrated with retaining springs to hold the saw blades against the guide faces, it is possible to use other saw retaining means known in the art, such as inset magnets, or fixed or sprung rollers, but it is generally desirable to provide means that allow the user to use the apparatus with the entire guide face unobstructed if desired. Other modifications are also possible within the scope of the invention: for example the saw guide carrier and planar element can be a single member and the guide element if detachable can also be reversible. The parts of the apparatus can also be adapted for more effective co-operation with other apparatus: for example special guide springs may be provided for engagement of a hacksaw blade.

Although to avoid undue repitition many of the features of the invention have been described and illustrated in different embodiments, it will be understood by those skilled in the art that these features can be combined within the scope of the invention in different ways than in the specific examples illustrated.

It will also be clear that because the apparatus is built up from a series of components that are preferably fully detachable, it is possible to combine these components in further ways than those illustrated.

Claims (29)

1. Saw guide apparatus comprising bearer means carrying saw guide means and being adapted to be placed upon a workpiece to locate the apparatus against the workpiece for said saw guide means to define the orientation of a saw guide plane relative to the workpiece, said saw guide means comprising a planar element mounted on a carrier member to present an upwardly extending saw guide face, the element being provided with location means for mounting it in the saw guide means in different positions relative to the bearer means.

2. Apparatus according to claim 1 wherein said carrier member is angularly adjustable about an upwardly extending pivot mounting on the bearer means.

3. Apparatus according to claim 1 or claim 2 wherein said element can be mounted in alternative angular orientations at 90 to each other about an axis transverse to the saw guide face, said saw guide face being directed obliquely to a longitudinal axis of the bearer means and thereby providing a saw guide plane inclined at the same angle either in the vertical direction or.transverse to said vertical direction, whereby the apparatus can be utilised for cutting dovetail pins and sockets in workpieces forming the respective members of dovertail corner joints.

4. Apparatus according to any one of claims 1 to 3 wherein said element is of elongate form and is locatable in alternative positions in which the longer dimension of its saw guide face extends either upwardly and downwardly or laterally.

5. Apparatus according to any one of the preceding claims wherein said element is adjustable to locate the saw guide face in different positions in the direction of the saw stroke.

6. Apparatus according to any one of the preceding claims wherein the saw guide means comprises a planar member that is loctable to extend in the direction of one of said mutually transverse faces and that comprises a drill bush mounting.

7. Apparatus according to any one of the preceding claims wherein the saw guide means is provided with a resilient member for urging the saw blade against said planar element, and said member is removably adjustable in position in accordance with the different positions of the planar element.

8. Apparatus according to claim 7 wherein said resilient member is of Uform and said planar element has means for receiving the resilient member in alternative positions in which the bend of the U-form is located either above or below the guide face

9. Saw guide apparatus comprising bearer means carrying saw guide means and being adapted to be placed upon a workpiece to locate the apparatus against the workpiece for said saw guide means to define the orientation of a saw guide plane relative to the workpiece, said saw guide means comprising a planar element arranged to present an upwardly extending saw guide face and provided with resilient means to urge a saw blade against the guide face, said resilient means comprising a U-form resilient member mounted in the saw guide means to be adjustable vertically of the saw guide face.

10. Apparatus according to claim 9 wherein said member can be secured in place in alternative positions in which the bend of the U-form is located either above or below the guide face.

11. Apparatus according to claim 9 or claim 10 wherein adjustable means are provided to urge the arms of the U together whereby to vary the retaining force exerted by the U-form member on an inserted saw blade.

1 2. Apparatus according to any one of claims 9 to 11 wherein the U-form member has a freely rotatable roller mounted at the bend of its U-form to protect the saw teeth when said bend is located lowermost.

1 3. Saw guide apparatus comprising bearer means arranged to be placed upon a workpiece and having faces defining location planes for mutually transverse faces of the workpiece, and saw guide means forming a part of or secured to said bearer means to provide a forwardly facing guide face defining the orientation of a saw guide plane relative to said workpiece faces, characterised in that the bearer means comprising at least two members that are adjustable secured together and the saw guide means being part of or being secured to a first of the bearer members, a further one of said bearer members being adjustably securable to said first member to provide a location plane rearwards of the saw guide means at an adjustable distance from the saw guide plane.

1 4. Apparatus according to claim 1 3 wherein the saw guide means are pivotally adjustable on the first bearer member.

1 5. Apparatus according to claim 1 3 or claim 1 4 wherein said bearer members are relatively rotatable to adjust the angular orientation of said further member relative to the saw guide plane.

1 6. Apparatus according to any one of claims 1 3 to 1 5 whereinsaid first bearer member has a bottom face capable of defining a top face location plane perpendicular to a workpiece location plane defined by a side face of said further or another member of the bearer means.

1 7. Apparatus according to claim 1 5 together with claim 1 6 wherein said second member is rotatable relative to the first member to a position at which it has a side face parallel to the saw guide plane providing said location face behind the saw guide plane.

1 8. Apparatus according to claim 1 6 or 1 7 wherein said further member is adapted to be secured to a top face of the first member and comprises at least one portion projecting below the first member to provide said side face location.

1 9. Apparatus according to any one of claims 1 3 to 1 8 wherein said further bearer member is of elongate form and has a terminal limb perpendicular to said location faces and providing said location plane rearwards of the saw guide means.

20. Apparatus according to any one of claims 1 3 to 1 9 wherein said second bearer member or a further bearer member is locatable in a position in which it projects forwardly through the saw guide plane to have a forward terminal portion beyond the saw guide plane and said first bearer member carrying the saw guide means, said terminal portion thereby providing an adjustable location plane spaced forwardly from the saw guide plane.

21. Apparatus according to claim 20 wherein said forward terminal portion has a vertically extending face adapted to support the apparatus against a vertical face of the workpiece.

22. Apparatus according to claim 20 or claim 21 wherein said projecting member or said terminal portion thereof is of L5orm with a horizontal limb extending through the saw guide plane at a level below the saw guide means, and an upwardly extending terminal limb forming said terminal portion.

23. - Apparatus according to any one of claims 20 to 22 wherein said forwardly projecting member has parallel terminal limbs at opposite ends and is reversible to dispose either of said limbs foremost with respect to the saw guide plane, at least one of said limbs being adapted to provide a forward location face for the workpiece rearwards of the saw guide plane.

24. Apparatus according to any one of claims 20 to 23 wherein said bearer means comprises three members the first member of the bearer means on which the saw guide means is mounted being attached to a second bearer member providing said location plane rearwards of the saw guide plane, and the third member being slidably adjustable to act as said projecting member providing said location plane forwards of the saw guide plane.

25. Apparatus according to any one of claims 1 3 to 1 9 wherein said second or further bearer member is of U-form or comprises a U-form portion in which both end limbs o, the U-form can be employed as alternative location faces.

26. Apparatus according to any one of claims 1 3 to 25 wherein said further and/or other bearer members have a substantial longitudinal and vertical extent such as to provide planar location for the apparatus in both said directions against the workpiece.

27. Apparatus according to any one of claims 1 3 to 26 wherein the saw guide means extends above the bearer means and comprises a guide face element that is upwardly and downwardly adjustable to be engageable with a top face of the workpiece.

28. Apparatus according to any one of claims 1 3 to 27 wherein the saw guide means comprises a planar member that is locatable to extend in the direction of one of said mutually transverse faces and that comprises a drill bush mounting.

29. Saw guide apparatus constructed and arranged for use and operation substantially as described herein with reference to any of the examples illustrated in the accompanying drawings.