HH45 Harvester Head, HH55 Harvester Head, HH65 Harvester Head and HH75 Harvester Head (CABS) Caterpillar

Note: Under normal operating conditions, a chain may be sharpened until the top plate of the cutter is gone. The chain should then be replaced. The chain needs to be sharpened when the cutting speed is drastically reduced during cutting operations. The chain needs to be sharpened when smoke is present during cutting operations. The tree will be burned at the cut location. A sharp chain is very important for optimum performance.

Reference: Remove the saw chain from the saw bar. Refer to Operation and Maintenance Manual, "Saw Chain - Remove/Install".

Note: Always inspect the chain before you sharpen the chain. Check the chain for bent drive links, broken cutters, and loose rivet heads. Replace all broken parts or damaged parts with new parts and/or replace the entire chain.

Sharpening a Saw Chain with a Round File

1. Remove the chain from the head.

2. Before you sharpen the chain, clean the oil and the grease from the chain.

3. Use a round file (7/32 inch) and a guide (7/32 inch) in order to sharpen the chain.

   Note: Use the correct file (size) for the chain that is being serviced.

Show/hide table



Illustration 1	g00823665
Side view of a cutter (1) File. (2) Cutter. (A) Height of the file.

4. Keep 20 percent of the diameter of the file (A) above the top plate of the cutter during sharpening.

   Note: Use the guide to hold file (1) in this position.

Show/hide table



Illustration 2	g00831477
(3) File holder.

5. Keep the filing angle line on the guide parallel with the chain.

Show/hide table



Illustration 3	g00831479

6. Sharpen all cutters on one side of the chain first. File each cutter from the inside to the outside. Rotate the chain and repeat the process for the cutters on the other side of the chain.

Show/hide table



Illustration 4	g00831483

7. If damage is present on the chrome surface of the top plates or the side plates, file the cutter until the damage is removed.

Show/hide table



Illustration 5	g00831635

8. Sharpen all cutters equally.

Show/hide table



Illustration 6	g00838580

9. Check the depth gauge after sharpening the cutters.

Show/hide table



Illustration 7	g00831637

10. Use the correct depth gauge tool in order to check the depth gauges after sharpening the cutters. Place the tool on top of the chain so the depth gauge protrudes through the slot in the tool. If the depth gauge extends above the slot then file the depth gauge until the gauge is level with the top of the tool. Use a flat file.

11. Install the chain. See Operation and Maintenance Manual, "Saw Chain - Remove/Install".

Sharpening a Saw Chain with a Grinder

1. Before you sharpen the chain, clean the oil and the grease from the chain.

Show/hide table



Illustration 8	g00839517

2. Set the grinding angle to 30° for the top plate. Set the cutting angle to 60° for the top plate on the grinder.

3. Use light intermittent strokes.

4. Sharpen all cutters equally.

5. Install the chain. See Operation and Maintenance Manual, "Saw Chain - Remove/Install".

Troubleshooting the Saw Chain

Most problems are caused by the three items that are listed below.

• Incorrect sharpening

• Lack of lubrication

• Incorrect chain tension

Probable Causes of Saw Chain Problems

Illustration 9	g00838579
Parts of a Cutter (4) Top plate. (5) Cutting corner. (6) Side plate. (7) Depth gauge. (8) Heel. (9) Toe.

Problem

Light abrasive damage on the cutting edges of top and/or side plates.

Cause Cutters came in contact with light abrasive materials.

Results The saw chain cuts very slowly.

Fix File the cutters back until all damage is removed.

Problem

The cutting edges of top and/or side plates are severely damaged.

Cause The cutters have come in contact with rocks, dirt, or sand.

Results The saw chain will not cut.

Fix File cutters back until all damage is removed.

Problem

Illustration 10	g00832232

The filing angle on the top plate of the cutters is too great.

Cause The angle on the top plate is excessive on the cutters.

Results The cutting angle on the cutter is very sharp. The cutters will blunt quickly.

Fix File the cutter at the correct angle.

Problem

Illustration 11	g00832235

The angle on the top plate is too small.

Cause The cutters are filed at less than the recommended angle that is required.

Results The saw chain cuts very slowly.

Fix File the cutters at the correct angle that is required.

Problem

Illustration 12	g00832239

The cutting angle on the top plate is too great.

Cause The file is held too low on the cutters. The file is too small.

Results The saw chain cuts fast for short time. The chain blunts rapidly.

Fix Use the proper file in order to sharpen the cutters.

Problem

Illustration 13	g00832240

The cutting angle on the top plate is too small.

Cause The file is held too high on the cutters. The file is too large.

Results The saw chain cuts slowly.

Fix Use the proper file in order to sharpen the cutters.

Problem

Illustration 14	g00832243

The hook in the side plate is too great.

Cause The file is held too low. The file is too small.

Results The saw chain cuts roughly. The cutters are quickly blunted.

Fix Use the proper file in order to sharpen the cutters.

Problem

Illustration 15	g00832313

The incorrect depth gauge was used.

Cause The wrong depth gauge was used. No depth gauge was used.

Results The saw chain cuts roughly.

Fix File the top plate to the proper depth gauge setting.

Problem

Illustration 16	g00832315

The depth gauge is set too high.

Cause The depth gauge was never lowered.

Results The saw chain cuts slowly. The chain and the rails are worn.

Fix Use the recommended depth gauge.

Problem

Illustration 17	g00832319

The tie straps on the cutters and opposite tie straps are cracked.

Cause The chain is blunt. The chain is not lubricated properly. The chain tension is too loose.

Results The heel on the plate is worn. The chain can break.

Fix Replace worn cutters and/or tie straps. Sharpen cutters properly. Use proper chain tension and plenty of lubrication.

Problem

The bottom of the drive links are straight or concave on the chain.

Cause The groove in the bar is too shallow. The groove in the nose bar is too shallow.

Results This increases the tendency to throw the chain from the bar.

Fix Replace the bar.

Problem

The front of the drive link and back of the drive link are damaged.

Cause The drive sprocket is worn.

Results Stretching of the chain occurs. Service life of the chain is shortened.

Fix Replace the sprocket.

Problem

The bottom of cutters and tie straps or the front of cutters and tie straps are damaged.

Cause The chain tension is incorrect.

Results The chain can break.

Fix Maintain proper chain tension.

Problem

The cut of the chain is uneven.

Cause Cutters on one side of the chain are damaged.

Results The bar and the chain get bound in the tree.

Fix File cutters back enough to remove all damage.

Probable Causes of Problems with the Saw Bar

Problem

Illustration 18	g00832405

The rails are worn down. The groove has become shallow.

Cause This is normal wear on the rails.

Results The chain rides on the bottom of the groove. This causes damage to the drive link.

Fix Replace the bar.

Problem

Illustration 19	g00832475

The outside edges of the rails develop frayed edges.

Cause This is normal wear on rails.

Results The frayed edges may break off. This may cause damage to the rail.

Fix Use a file in order to remove the frayed edges.

Problem

The rail is worn on one side of the bar.

Illustration 20	g00832476

Cause Cutters are damaged or blunt.

Results Incomplete cuts occur. The bar is binding during the cut.

Fix Replace the bar and the chain.

Problem

Illustration 21	g00832477

The rails around the tip of the nose bar show broken sections.

Cause The operator uses irregular operating techniques.

Results The rails will wear quickly. The chain will be damaged.

Fix Replace the bar and the chain.

Problem

Illustration 22	g00832478

The rails around the tip of the nose bar are split at the bottom of the bar.

Cause The operator uses irregular operating techniques.

Results The rails will wear quickly. The chain will be damaged.

Fix Replace the bar.

Problem

Illustration 23	g00832482

The rails on the bar or around the tip of the nose bar show blue discoloration.

Cause The operator uses irregular operating techniques. The chain is not lubricated properly.

Results The rails will wear quickly. The chain will be damaged.

Fix Replace the bar and the chain.

Problem

The rail is chipping in the middle of the bar.

Cause The operator uses excessive pressure on the bar during cutting operations. The chain is not lubricated properly. Cold conditions existed.

Results The rails will wear quickly. The chain will be damaged.

Fix Replace the bar and the chain.

Problem

The rail on one side of the bar is worn.

Cause The cutters are damaged or blunt on one side.

Results Incomplete cuts occur. The bar is binding during the cut.

Fix Replace the bar and the chain.

Problem

The rails are spread apart.

Illustration 24	g00832889

Cause The chain was struck by the tree. The chain was pushed sideways. This forced the drive links against the rails. The rails are spread apart.

Results Incomplete cuts occur. The bar is binding during the cut.

Fix Use a drive link in the groove as a spacer and hammer the rails together. Adjust the saw bar return. Avoid moving the log when the bar is out of the saw box.