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Level 1 Diploma in Carpentry and Joinery

PowerPoint presentation

Power Saws

Unit 114: Prepare and use carpentry and joinery Portable Power Tools

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Level 1 Diploma in Carpentry and Joinery

Objectives

To be able to:

5.1 State uses of portable power saws

5.2 State the purpose of operation guards on portable power chop saws

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Level 1 Diploma in Carpentry and Joinery

Hand-held Circular SawAlso known as a plunge saw or Skil saw (for the company that invented it).

Can be used for both crosscut and rip cuts (so long as the timber is always safely and securely anchored).

The blade is plunged down (carefully) into the timber and lifted again after the cut is made.

On most models, the blade can be tilted for bevel cuts.

A proprietary rail allows quick and accurate ripping of sheet material.

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Level 1 Diploma in Carpentry and Joinery

Chop SawThe “chop saw” is a circular saw permanently mounted on a frame, used for crosscutting timber only.

The bed and fence can swing through 180° under the stationary blade arm, allowing miters to be cut across the face of the timber.

The pivoting arm may also be designed to tilt, allowing bevels to be cut through the thickness of the timber (and allowing compound angles: combined bevel and mitre).

The plunge arm may also be designed to slide, allowing crosscuts through much wider boards.

The saw must ALWAYS be fixed securely on a proprietary stand (or bench-fixed).

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Level 1 Diploma in Carpentry and Joinery

The purpose of the operation guards on chop saws is to enclose the saw blade as much as possible for as long as possible.

By design, possibility of contact with the turning blade is minimised due to the self-closing guard. When the unit is lowered, this guard will retract just enough to allow the cut.

Before operation, the user must check that all guards are in place and working. If a guard seems slow to return to its normal position, it should be reported to your supervisor immediately for adjustment or repair.

Operation Guards on Chop Saws

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Level 1 Diploma in Carpentry and Joinery

Reciprocating SawsWith both sabre saw (top) and jigsaw (bottom), the cutting action is achieved through a push-and-pull (reciprocating) motion of the blade.

The sabre saw is often used in refurbishment, to chop out obstinate framing.

The jigsaw is used by carpenters for curved work and cutting out shapes in the centre of boards (once a pilot hole is drilled).

The jigsaw can also be used to cut through mild metal (if an appropriate blade is fitted).