AU783741B2 - Improved timber milling apparatus - Google Patents

Description

IMPROVED TIMBER MILLING APPARATUS FIELD OF THE INVENTION The present invention relates to milling of timber and in particular to a portable timber mill.

BACKGROUND ART Portable timber mills in general are known.

One type of mill comprises a rail that is fixed to the log or timber to be milled. This mill is adapted to allow the saw to be used only in the vertical position. The mill also comprises a roller head manufactured of cast iron and fitted with replaceable bearings which is adapted to be rolled or otherwise moved along the length of the rail. An adjustable arm member slides transversely through the roller head. The arm member has a first end which is adapted to extend through the bar of a conventional chainsaw and thereby fix the chainsaw to the mill. A nut or another fixing means is placed on the other side of the bar to achieve this purpose.

The adjustable arm member is movable in a direction transverse to the rail in order to adjust the width of the plank or slab cut. The roller head may also comprise a winch kit to allow the imposition of the required force on the chainsaw to push it through the timber to be cut. By winding the winch, the chainsaw is pulled through the timber, cutting as it moves.

The rail in this type of mill is a standard 4-meter length although extension rails are also available in 2-meter lengths. The extension rails interlink with the standard rail to lengthen the mill.

The prior art device is sold with titanium chainsaw bars that have been pre-drilled with holes to allow the positioning of the arm member.

The major disadvantage of this type of mill is that in order for the mill to function, the log or timber to be cut must be elevated off the ground, usually on dunnage or logs placed transversely under the main log. This allows the tip of the saw to protrude under the log to be cut. The log must therefore be lifted which may be extremely difficult for large logs and/or logs in inaccessible places. Another disadvantage is the mill makes no allowance for cutting in both horizontal and vertical orientations.

Another type of device is a mill that uses a chainsaw in a horizontal orientation. The mill consists of a plurality of arm members which are oriented perpendicularly to the direction of cutting. The arm members may rest on the log to be cut or on slabbing rail members placed on the log.

There is also a means to hold the chain saw fixed in position relative to the arm members. Additional members allow the spacing of the cutting chain from the arm members resting on the log, in order to control the thickness of the slab to be cut.

This device only allows cutting in a horizontal orientation. The mill makes no allowance for cutting in both horizontal and vertical orientations. The design of the mill to rest on the log to be cut or on the slabbing rail members does not allow for the use of friction reducing devices and so the force that must be used to push the cutting chain through the log is large, often requiring more than one person to achieve it.

Alternatives to the use of a chainsaw mill are the use of large circular saw mills or band saw mills. These types of mills have certain restrictions. Circular saw mills are very expensive and are generally not portable. The types that are portable cannot be used to cut large diameter logs. Circular saw blades can only cut slabs up to half their diameter and this means the when cutting large logs, extremely large blades must be used.

The larger the blade is the more easily it can be damaged and the more expensive it is to do so. Circular saw mills are also generally bulky devices requiring a stable flat footing and once set up are not easily moved. This requires that logs to be cut must be brought to the mill site. This means the large logs must be moved using heavy machinery which increases the expense and complexity of the milling operation.

Band saw mills are ideally used for medium sized straight logs.

They also require a flat stable footing. The setup of a band saw requires that the log to be cut is elevated and this causes difficulty for large logs and/or inaccessible positions. The band saw blade used is often fragile and easily damaged. Once damaged, the blade is expensive to replace.

OBJECT OF THE INVENTION The present invention is directed to an improved timber milling apparatus, which may at least partially overcome the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

In one form, the invention resides in an improved timber milling apparatus for use with a saw, comprising a main ladder rail assembly having two spaced apart longitudinal side rail members, at least one endpiece located transversely between and attached to an end of the two longitudinal rail members and a plurality of spaced apart transverse members extending between and attached to the two longitudinal side rail members, at least one ground bearing leg assembly releasably attachable to a transverse endpiece of the main ladder rail assembly, having means for adjusting the height of the attached main ladder rail assembly, and a saw carriage having means for releasably fixing the saw thereto and means for slideably moving the saw carriage and the affixed saw, along the main ladder rail assembly.

The main ladder rail assembly may preferably be manufactured from strong yet relatively lightweight material, a light metal such as galvanized iron being an example of such a material. Aluminium may also be used in the construction.

The main ladder rail assembly may suitably possess a transverse member at each end of the rail to provide a rectangular appearance. This transverse endpiece may also provide a suitable member for attachment of the main ladder rail assembly to the at least one ground bearing leg assembly. There may suitably be a hole drilled through the endpiece through which a bolt or other fastening member may pass in order to attach the main ladder rail assembly to the at least one ground bearing leg assembly.

The main ladder rail assembly may preferably have the appearance of a conventional ladder with endpieces located at either end.

The spaced apart transverse members may preferably have the effect of strengthening the main ladder rail assembly.

One of the two longitudinal side rail members may preferably have a protrusion extending perpendicularly from the side rail in a direction away from but parallel to the transverse members. This protrusion may preferably extend over the entire length of the side rail. The protrusion may suitably extend from adjacent the uppermost flat surface of the side rail and also be flush with that uppermost surface.

Each at least one ground bearing leg assembly may preferably be substantially similar. Each leg assembly may suitably have two spaced apart longitudinal leg members, at least one ground bearing member located transversely attached linking the lower ends of the two longitudinal leg members and a plurality of spaced apart transverse members extending between and attached to the two longitudinal leg members.

Each leg assembly may preferably be manufactured from hollow box section to provide the assembly with strength but remaining lightweight.

Each longitudinal leg member may suitably have a channel located so as to oppose the channel located on the other leg member of the same leg assembly. This channel will preferably act as reinforcing for the leg members and also act as a guide for the means for adjusting the height of the attached main ladder rail assembly. The channel may suitable extend along the length of each leg member.

Each channel will have two walls and a base. The base of the channel on one leg member will suitably face the base of the channel on the opposed leg member of the same leg assembly. Each channel wall will suitably have a lip.

Each channel may also have an angled protrusion extending from the lip of a channel wall in a direction away from the leg members. This protrusion may preferably extend over the entire length of the channel.

The means for adjusting the height of the attached main ladder rail assembly may preferably comprise a hoist carriage and an associated winch apparatus that is attached to one of the leg members.

There may preferably be a hoist carriage at either end of the attached main ladder rail assembly, located between the two leg members of the same leg assembly. Each hoist carriage may preferably be located at least partially within the opposed channels on leg members of the same leg assembly.

Each hoist carriage may preferably comprise an H-shaped body portion. The H-shaped body portion will have a substantially vertical orientation. On each of the legs of the H-shaped body portion there may preferably be a plurality of bearings to reduce the friction between each leg and the channel in which each leg is at least partially disposed. Suitably there may be an extra group of bearings to interact with the angled protrusion extending from the lip of each channel wall. This will allow easier and more precise location of the hoist carriage and reduce any free play which the hoist carriage may have within the channel.

There may also be an indicator means to show the user where the hoist carriage is located relative to the leg assembly.

There may preferably be at least one pulley associated with the crosspiece of the H-shaped body portion. There may suitably be two pulleys to allow easier movement of the hoist carriage. Each pulley will suitably be able to swivel about its attachment means. The pulleys may preferably be located on the upper face of the crosspiece.

There may suitably be more than one crosspiece. Associated with one of the crosspieces of the body of the hoist carriage will preferably be a cradle member. The cradle member will extend perpendicularly from the Hshaped body portion in a substantially horizontal direction and then upwards.

The cradle will preferably receive the endpiece of the main ladder rail assembly. There may suitable be a hole drilled thought the vertical portion of the cradle and the crosspiece to allow the endpiece to be fixed to the cradle usually by passing a bolt through all portions and securing.

Each leg assembly may preferably also have a detachable headpiece. The detachable headpiece may preferably comprise a transverse crosspiece with a portion depending from each end of the crosspiece. Each depending portion may preferably be sized to be received within the hollow longitudinal leg member to facilitate the removal and replacement of the headpiece.

Positioned on the upper side of the transverse crosspiece will suitably be at least one fixed friction reducing means for the winch cable.

The cable from the winch may preferably pass from the winch upward to the fixed friction reducing means attached to the transverse crosspiece on the headpiece, through a hole in the crosspiece, though the pulleys located on the crosspiece of the hoist carriage and continue upwards to be fixed to the transverse crosspiece on the headpiece. In this way, winding the handle of the winch will raise or lower the hoist carriage and the attached main ladder rail assembly.

The saw carriage may preferably have four arm members arranged to form a substantially rectangular base. Two of the arm members may preferably be oriented in the same direction as the cutting direction and the remaining two arm members oriented in a perpendicular direction. The base may suitably be manufactured from hollow metal box section. The base may also preferably have dimensions such that it may be slidably movable on the main ladder rail assembly.

When in position on the main ladder rail assembly, the saw carriage has a depending portion on either side of the main ladder rail assembly to restrict the movement of the saw carriage. When in position, the saw carriage may only move in a longitudinal direction along the main ladder rail assembly.

The saw carriage may also be equipped with bearings to reduce the friction between the sliding surfaces and to maintain its position on the main ladder rail assembly. The bearings may include a set which interacts with the protrusion extending perpendicularly from the side rail.

The saw carriage may preferably include at least one slabbing attachment member located at an angle to the direction of cutting. The slabbing attachment allows a user to make cuts in the timber or log longitudinally and substantially parallel to the ground. The saw cutting surface will be aligned accordingly. Each slabbing attachment member may suitably be manufactured from hollow metal box section. There may preferably be two such members. These members will suitably allow the attachment of a slabbing attachment to the saw carriage.

The slabbing attachment preferably comprises at least two support members which are positioned through the hollow slabbing attachment members. There may be an endpiece attached to either end of the two support members. Each of these endpieces is associated with a means for releasably fixing the saw thereto. The endpieces also have a means for adjusting the space between the cutting surface of the saw and the support members. The slabbing attachment may also preferably have a means to allow the user to grip the slabbing attachment associated with it. As a consequence of the angled support members, the cutting surface of the saw will also be at an angle to the log or timber.

The saw carriage may preferably also include at least one ripping attachment member located perpendicular to the direction of cutting.

There will preferably be two ripping attachment members, one positioned on either of the arm members oriented in the cutting direction. The ripping attachment members will preferably be semicircular members which are able to clamp a hollow box section member between the inner surface of the semicircle and the saw carriage. In this manner, the box section may be rotated around the horizontal to provide adjustable depth in cutting. The actual ripping arm members may then be inserted into the hollow box section clamped to the saw carriage. The ripping arm members may be clamped into position using a friction clamp with a threaded screw for adjustment. These members will suitably allow the attachment of the saw to the saw carriage.

The ripping attachment allows a user to make cuts in the timber or log longitudinally and substantially perpendicularly to the ground. The saw cutting surface will be aligned accordingly.

Each leg member may preferably have at least one attachment member extending in a direction perpendicular to the cutting direction in the mill. There will suitably be more than one attachment member. There may suitably be a first attachment member extending at an angle toward the ground from each leg member and also a second attachment member extending in a substantially horizontal direction. The second attachment member may suitably be positioned lower on the leg member than the first attachment member. The attachment members are to facilitate the attachment of stabilizing leg members to add to the safety of the mill.

Attachment of the stabilizing leg members may be accomplished using a conventional pin and slot attachment means.

There may also preferably be at least two types of stabilizer leg member. The first type of stabilizer leg member is associated with the first attachment member. This stabilizer leg member may suitably have a groundbearing member disposed at its lower end. The ground-bearing member may suitably have a hole for the insertion of a tent peg or like device for fixing the leg member to the ground. The upper end of the first stabilizer leg member may suitably have at least one hole for the use of a pin and slot attachment means to attach it to the leg member assembly.

The second type of stabilizer leg member is associated with the second attachment member. This stabilizer leg member may suitably have an angled portion disposed at its outer end to receive a stabilizer bar. The angled portion may suitably have a hole for the insertion of a pin or like device for fixing the second stabilizing leg member to the stabilizer bar. The inner end of the second stabilizer leg member may suitably have at least one hole for the use of a pin and slot attachment means to attach it to the leg member assembly. The second stabilizer leg member may receive the first stabilizer leg member in its hollow interior. The stabilizer bar may suitably be important in order to maintain the stability of the mill, especially when used on uneven ground.

In any non-permanent attachment in the mill apparatus, the preferred method of attachment may be a friction or clamping type attachment wherein a threaded screw member may be tightened against a member to hold it in position.

"Slabbing" in this description refers to cutting a log in a longitudinal direction substantially parallel to the ground or other surface.

"Ripping" in this description refers mainly to cutting a log in a longitudinal direction substantially perpendicular to the ground or other surface. Ripping may also be done at any angle to the ground.

BRIEF DESCRIPTION OF THE DRAWINGS Various embodiments of the invention will be described with reference to the following drawings, in which: Figure 1 shows an end perspective view of the mill adapted for slabbing.

Figure 2 shows a close up of the main ladder rail assembly with the saw carriage and slabbing attachment in place.

Figure 3 shows a perspective view of the mill adapted for ripping.

Figure 4 shows a top perspective view of the saw carriage.

Figure 5 shows a reverse perspective view of the saw carriage.

Figure 6 shows a top perspective view of the saw carriage with the ripping attachment in place.

Figure 7 shows a side perspective view of the saw carriage and the slabbing attachment removed from the main ladder rail assembly.

Figure 8 shows a perspective view of a leg assembly showing the winch and the hoist carriage.

Figure 9 shows a close-up perspective view of the hoist carriage removed from the leg assembly.

Figure 10 shows a perspective view of the leg assembly which has been removed from the mill.

Figure 11 shows an exploded schematic perspective view of a leg assembly.

Figure 12 shows a schematic perspective view of the hoist assembly.

Figure 13 shows a schematic perspective view of the main ladder rail assembly.

Figure 14 shows a schematic perspective view the first stabilizer leg member.

Figure 15 shows a schematic perspective view the second stabilizer leg member.

Figure 16 shows an exploded schematic perspective view the slabbing assembly.

Figure 17 shows a side view the ripping assembly.

Figure 18 shows a bottom schematic view the saw carriage.

Figure 19 shows an end view the saw carriage.

Figure 20 shows a top view the saw carriage.

Figure 21 shows a side view the saw carriage.

BEST MODE According to the present invention, an improved timber milling apparatus 10 is provided.

As can be seen from the Figure 1, the improved timber milling apparatus 10 is designed for use with a chainsaw 11, and comprises a main ladder rail assembly 12 having two spaced apart longitudinal side rail members 13, two endpieces 14 located transversely between and attached to an end of the two longitudinal rail members 13 and a plurality of spaced apart transverse members 15 extending between and attached to the two longitudinal side rail members 13, two leg assemblies 16 releasably attachable to the transverse endpieces 14 of the main ladder rail assembly 12, having a winch 17 for adjusting the height of the attached main ladder rail assembly 12, and a saw carriage 18 having clamps 19 for releasably fixing the chainsaw 11 thereto and a plurality of bearings 20 for slideably moving the saw carriage 18 and the affixed chainsaw 11, along the main ladder rail assembly 12.

The main ladder rail assembly 12 best seen in Figure 13 is manufactured from strong yet relatively lightweight metal, such as galvanized iron.

The main ladder rail assembly 12 has a transverse endpiece 14 at each end of the assembly 12 to provide a rectangular appearance. Each transverse endpiece 14 also provides a suitable member for attachment of the main ladder rail assembly 12 to the leg assemblies 16. There is a hole 21 drilled through the endpiece 14 through which a bolt 22 passes to attach the main ladder rail assembly 12 to the leg assemblies 16.

The main ladder rail assembly 12 resembles a conventional ladder with endpieces 14 located at either end. The spaced apart transverse members 15 have the effect of strengthening the main ladder rail assembly 12.

One or both of the longitudinal side rail members 13 has a lip 23 extending perpendicularly from the side rail 13 in a direction away from, but parallel to the transverse members 15. This lip 23 extends over the entire length of the side rail 13. The lip 23 is located adjacent the uppermost flat surface of the side rail 13 and is also flush with that uppermost surface.

Each of the leg assemblies 16, best seen in Figure 11, are substantially similar. Each leg assembly 16 has two spaced apart longitudinal leg members 24, at least one base member 25 located transversely attached linking the lower ends of the two longitudinal leg members 24 and a plurality of spaced apart transverse leg members 26 extending between and attached to both longitudinal leg members 24.

Each leg assembly 16 is manufactured from hollow box section to provide the assembly with strength but remaining lightweight. Each longitudinal leg member 24 has a channel 27 located so as to oppose the channel 27 located on the other leg member 24 of the same leg assembly 16.

This channel 27 acts as reinforcing for the leg members 24 and also as a guide for a hoist carriage 28. The channel 27 extends along the length of each leg member 24.

Each channel 27 will have two walls 29 and a base 30. The base of the channel 30 on one leg member 24 faces the base of the channel on the opposed leg member 24 of the same leg assembly 16. One of the channel walls 29 has a lip 31.

The lip 31 is an angled extension from the channel wall 29 in a direction away from the leg members 16. The lip 31 extends over the entire length of the channel 27.

To adjust the height of the attached main ladder rail assembly 12, a hoist carriage 25 is located in the channel 27 and an associated winch 17 is attached to the leg assembly 16 at either end of the mill apparatus Each hoist carriage 25 is located at least partially within the opposed channels 27 on longitudinal leg members 24 of the same leg assembly 16.

Each hoist carriage 25 best seen in Figure 12 comprises an Hshaped body portion 32. The H-shaped body portion 32 has a substantially vertical orientation. On each of the legs 33 of the H-shaped body portion 32 there are a plurality of bearings 20 to reduce the friction between each leg 33 and the channel 27 in which each leg 33 is at least partially disposed. There are a group of bearings 20 to interact with the angled lip 31.

There is also a tape measure 34 to show the user where the hoist carriage 28 is located relative to the leg assembly 16.

There are two pulleys 34 fixed to the crosspiece 35 of the Hshaped body portion 32. Each pulley 34 can swivel about its attachment point. The pulleys 34 are located on the upper face of the crosspiece A cradle member 36 extends from the lower portion of the crosspiece 35 of the hoist carriage 28. The cradle member 36 extends perpendicularly from the H-shaped body portion 32 in a substantially horizontal direction and then upwards. The cradle 36 receives the endpiece 14 of the main ladder rail assembly 12. There is a hole drilled thought the vertical portion of the cradle and the crosspiece 35 allowing the endpiece 14 to be fixed to the cradle 36 by passing a bolt 22 through all portions and securing.

Each leg assembly 16 has a detachable headpiece 37. The detachable headpiece 37 comprises a transverse crosspiece 38 with a portion 39 depending from each end of the crosspiece 38. Each depending portion 39 is slightly smaller than the internal dimensions of the leg members 24 so it can be received within the hollow longitudinal leg members 24 to facilitate the removal and replacement of the headpiece 37.

Positioned on the upper side of the transverse crosspiece 38 are two fixed runner wheels 40 for the winch cable 41.

The cable 41 from the winch 17 passes from the winch 17 upward to the fixed runner wheels 40 attached to the transverse crosspiece 38 on the headpiece 37, through a hole in the crosspiece 38, though the pulleys 34 attached to the crosspiece 38 of the hoist carriage 28 and continue upwards to be fixed to the transverse crosspiece 38 on the headpiece 37.

Therefore, winding the handle of the winch 17 raises and lowers the hoist carriage 28 and the attached main ladder rail assembly 12.

The saw carriage 18 best seen in Figures 18-21 is constructed from four arm members 42 arranged to form a substantially rectangular base.

Two of the arm members 42 are oriented in the same direction as the cutting direction and the remaining two arm members 42 are oriented in a perpendicular direction. The base is manufactured from hollow metal box section. The base also has dimensions such that it may be slidably movable on the main ladder rail assembly 12.

When in position on the main ladder rail assembly 12, the saw carriage 18 has an arm member 42 on either side of the main ladder rail assembly 12 to restrict the lateral movement of the saw carriage 18.

Therefore, the saw carriage 18 can only move in a longitudinal direction along the main ladder rail assembly 12.

The saw carriage 18 is also equipped with bearings 20 to reduce the friction between the sliding surfaces and to maintain its position on the main ladder rail assembly 12. There is a set of bearings 20 which interacts with the lip 23 on the longitudinal side rail 13.

The saw carriage 18 can be adapted to include the slabbing attachment 43 best seen in Figures 2, 7,and 16, oriented at an angle to the direction of cutting. The slabbing attachment 43 allows a user to make cuts in the timber or log longitudinally and substantially parallel to the ground. The saw carriage has two slabbing attachment members 44 manufactured from hollow metal box section. These members 44 allow the attachment of the slabbing attachment 43 to the saw carriage 18.

The slabbing attachment 43 comprises two or three support members 45 positioned through the hollow slabbing attachment members 44.

There is a slabbing endpiece assembly 46 attached to either end of the two support members 45. Each of these endpiece assemblies 46 is associated with a clamp 19 for releasably fixing the chainsaw 11 thereto. The endpiece assembly 46 can also be adjusted to change the space between the cutting surface of the chainsaw 1 land the support members 45. The user can also grip the slabbing attachment 43 at the endpiece assembly 46. As a consequence of the angled support members 45, the cutting surface of the chainsaw 11 will also be at an angle to the log or timber.

The saw carriage 18 also includes two ripping attachment members 47 welded perpendicular to the direction of cutting, one positioned on either of the arm members 42 oriented in the cutting direction. The ripping attachment members 47 are circular members which are able to clamp a hollow box section member 48 between the inner surfaces of the member 47.

In this manner, the box section 48 may be rotated around the horizontal to provide adjustable depth in cutting. The ripping arm member 49 may then be inserted into the hollow box section 48 clamped to the saw carriage 18. The ripping arm member 49 is clamped into position using a friction clamp with a threaded screw 50 for adjustment. The ripping attachment allows a user to make cuts in the timber or log longitudinally and substantially perpendicularly to the ground.

Each leg member 24 also has two attachment members extending in a direction perpendicular to the cutting direction in the mill There are a first attachment member 52 extending at an angle toward the ground from each leg member and also a second attachment member 51 extending in a substantially horizontal direction. The second attachment member 51 is positioned lower on the leg member 24 than the first attachment member 52. The attachment members are to facilitate the attachment of stabilizing leg members 53 to add to the safety of the mill 10. Attachment of the stabilizing leg members 53 is accomplished using a conventional pin and slot attachment means.

There are also at least two types of stabilizer leg member 53.

The first type of stabilizer leg member 54 is associated with the first attachment member 52. This first stabilizer leg member 54 has a groundbearing member 55 disposed at its lower end. The ground-bearing member has a hole for the insertion of a tent peg 56 or like device for fixing the leg member 24 to the ground. The upper end of the first stabilizer leg member also has a hole for the use of a pin and slot attachment means to attach it to the leg member 24.

The second type of stabilizer leg member 57 is associated with the second attachment member 51. This second stabilizer leg member 57 has an angled portion 58 disposed at its outer end to receive a stabilizer bar 59. The angled portion 58 has a hole for the insertion of a pin 60 or like device for fixing the second stabilizing leg member 57 to the stabilizer bar 59.

The inner end of the second stabilizer leg member 57 has a hole for the use of a pin and slot attachment means to attach it to the leg member 24. The second stabilizer leg member 57 receives the first stabilizer leg member 54 in its hollow interior.

In the present specification and claims, the word "comprising" and its derivatives including "comprises" and "comprise" include each of the stated integers but does not exclude the inclusion of one or more further integers.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted by those skilled in the art.

Claims (16)

1. A timber milling apparatus for use with a saw, comprising a main ladder rail assembly having two spaced apart longitudinal side rail members, at least one endpiece located transversely between and attached to an end of the two longitudinal rail members and a plurality of spaced apart transverse members extending between and attached to the two longitudinal side rail members, at least one ground bearing leg assembly releasably attachable to the transverse endpiece of the main ladder rail assembly, having means for adjusting the height of the attached main ladder rail assembly, and a saw carriage having means for releasably fixing the saw thereto and means for slideably moving the saw carriage and the affixed saw, along the main ladder rail assembly.

2. The timber milling apparatus of claim 1 manufactured of galvanized iron or aluminium.

3. The timber milling apparatus of claim 1 or 2 wherein the saw carriage has four arm members arranged to form a substantially rectangular base, two of the arm members oriented in the same direction as the cutting direction and the remaining two arm members oriented in a perpendicular direction, the saw carriage having dimensions such that it is slidably movable on the main ladder rail assembly.

4. The timber milling apparatus of any one of the preceding claims wherein the saw carriage when in position can only move in a longitudinal direction along the main ladder rail assembly.

5. The timber milling apparatus of any one of the preceding claims wherein the saw carriage has bearings to reduce the friction between the sliding surfaces and to maintain its position on the main ladder rail assembly.

6. The timber milling apparatus of any one of the preceding claims wherein the saw carriage includes a slabbing attachment allowing a user to make cuts longitudinally and substantially parallel to the ground.

7. The timber milling apparatus of claim 6 wherein the slabbing attachment comprises at least two substantially parallel support members which are releasably attached to the saw carriage and an endpiece linking the adjacent ends of the two support members having means to attach a saw to the endpieces.

8. The timber milling apparatus of claim 7 wherein each of the endpieces is associated with a means for adjusting the space between the cutting surface of the saw and the support members.

9. The timber milling apparatus of any one of claims 6-8 wherein the slabbing attachment is oriented such that the cutting surface of the saw is at an angle to the log or timber.

The timber milling apparatus of any one of claims 1 to 5 wherein the saw carriage includes a ripping attachment allowing a user to make cuts in the timber or log longitudinally and substantially perpendicularly to the ground.

11. The timber milling apparatus of claim 10 wherein the ripping attachment comprises an arm member releasably attached to the saw carriage and a means for attaching a saw to the arm member.

12. The timber milling apparatus of either one of claim 10 or 11 wherein the ripping attachment is oriented such that the cutting surface of the saw is at an angle to the log or timber.

13. The timber milling apparatus of any one of the preceding claims wherein the means for adjusting the height of the main ladder rail assembly comprises a hoist carriage and an associated winch apparatus associated with the at least one leg assembly.

14. The timber milling apparatus of claim 13 wherein there is a hoist carriage at either end of the main ladder rail assembly, associated with the leg assembly at that end.

The timber milling apparatus of any one of the preceding claims wherein the at least one leg assembly has attachment members to facilitate the attachment of stabilizing leg members to add to the safety of the mill.

16. The timber milling apparatus of any one of the preceding claims wherein any non-permanent attachment in the mill apparatus is a 18 friction or clamping type attachment wherein a threaded screw member is used. Dated this 30 th day of May, 2002 Daniel Koefoed by his Patent Attorneys CULLEN CO