Makita UC4050A, UC4550A Sharpening the saw chain, Sharpen the saw chain when, Sharpening criteria

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Sharpening the saw chain

CAUTION:

Always withdraw the mains plug and wear safety gloves when performing work on the saw chain.

006924

Sharpen the saw chain when:

Mealy sawdust is produced when damp wood is cut;

The chain penetrates the wood with difficulty, even when heavy pressure is applied;

The cutting edge is obviously damaged;

The saw pulls to the left or right in the wood. The reason for this behavior is uneven sharpening of

the saw chain, or damage to one side only.

Sharpen the saw chain frequently, but remove only a little material each time.

Two or three strokes with a file are usually sufficient for routine resharpening. When the saw chain has been resharpened several times, have it sharpened in MAKITA authorized service center.

Sharpening criteria:

− All cutter length must be equal. Cutters of differing

length prevent the chain from running smoothly,

and may cause the chain to break.

− Do not sharpen the chain once a minimum cutter

length of 3 mm has been reached. A new chain

must then be fitted.

 

 

− The chip thickness is determined by the distance

between the depth gauge (round nose) and the

cutting edge.

 

 

 

− The best cutting results are obtained with following

distance between cutting edge and depth gauge.

 

Chain blade 91PX: 0.65 mm

1

2

1

2

1. Cutting length

2. Distance between

 

 

 

 

 

 

cutting edge and

 

 

 

 

depth gauge

 

 

 

 

3. Minimum 3 mm

3

1

 

 

 

 

 

 

 

014456

 

 

 

 

WARNING:

An excessive distance increases the risk of kick-back. − The sharpening angle of 30 ° must be the same on all cutters. Differences in angle cause the chain to run roughly and unevenly, accelerate wear, and

lead to chain breaks.

− The side plate angle of the cutter is determined by the depth of penetration of the round file. If the specified file is used properly, the correct side plate angle is produced automatically.

− Side plate angle for each saw chain are as follows: Chain blade 91PX: 80 °

1.Side plate angle

 

30

30

 

1

1

014455

 

File and file guiding

Use a special round file (optional accessory) for saw chains to sharpen the chain. Normal round files are not suitable.

Diameter of the round file for each saw chain is as follows:

Chain blade 91PX: 4.0 mm

The file should only engage the cutter on the forward stroke. Lift the file off the cutter on the return stroke.

Sharpen the shortest cutter first. Then the length of this shortest cutter becomes the standard for all other cutters on the saw chain.

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Guide the file as shown in the figure.

The file can be guided more easily if a file holder (optional accessory) is employed. The file holder has markings for the correct sharpening angle of 30 ° (align the markings parallel to the saw chain) and limits the depth of penetration (to 4/5 of the file diameter).

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Contents Electric Chain Saw Specifications SymbolPower supply English Original instructionsGeneral Power Tool Safety Warnings Chain saw safety warnings Additional Safety Rules Proper usePersonal protective equipment Protection against electric shockKickback Safety features MaintenanceTransport and storage First aidFor Model UC3050A, UC3550A, UC4050A, UC4550A Designation of PartsFor Model UC3051A, UC3551A, UC4051A, UC4551A Assembly Removing or installing sprocket coverRemoving or installing saw chain For nut modelsAdjusting dial Adjusting saw chain tension Switch actionOperation Engaging extension cordChecking the switch action Checking the chain tensionAdjusting the chain lubrication Checking the chain brakeChecking the chain oiler Checking the run-down brakeBucking LimbingBurrowing and parallel-to-grain cuts FellingCleaning the chain saw MaintenanceChecking the plastic housing Sharpening the saw chain Sharpen the saw chain whenSharpening criteria File and file guidingCleaning the guide bar and lubricating the return sprocket Cleaning the oil guideNew saw chains Maintaining the chain and run-down brakesReplacing carbon brushes Storing toolOptional Accessories Trouble ShootingPossible cause Remedy Makita Corporation