l2 bench joinery unit 211 power point presentation 1

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Level 2 Diploma in Bench Joinery

PowerPoint presentation

Parts of a machine

Unit 211: Set up and operate a circular saw



Identify the components of a circular sawEnable learners to:

• know the regulations and guidance covering circular saw

• identify components of a circular rip saw

• state the potential faults in relation to a circular rip saw

• describe the procedure to follow on identification of faults.



Safe use of woodworkingCircular saws are governed by the following regulations and guidance:

• Provision and Use of Work Equipment Regulations 1998 as applied to woodworking machinery

• Approved Code of Practice and guidance.

For full details go to www.hse.gov.uk/pubns/priced/l114.pdf

http://www.hse.gov.uk/pubns/priced/l114.pdf



Accident statistics for circular saw benchesAccidents at circular saw benches account for around 35% of the total accidents recorded at woodworking machines.

Help prevent accidents by:

• carrying out risk assessments and ensuring control measures are followed

• ensuring that all operators are trained, competent and authorised

• ensuring that all guarding is available and correctly positioned

• carrying out regular maintenance on machines

• ensuring that operators follow current safe working practices at all times.



The circular rip sawThe hand fed circular rip saw is primarily designed for cutting along the grain direction (known as ripping).

There are several common ways of ripping timber:

• flatting: this is sawing the timber to width.

• deeping: this is sawing the timber to thickness.

• bevelling: this is sawing the timber at an angle.

Image courtesy of www.drapertools.com. Reproduced with permission.



Example of flat cutting• Flat cutting timber to the required size.

• The saw blade cuts through the thinnest section of the timber.

• Do not stand directly in line with the saw cut but slightly to the left.

Image courtesy of the Health and Safety Executive, information sheet 16. Reproduced with permission.



Example of deep cuttingDeep cutting timber to the required size.

The saw blade cuts through the thickest section of the timber.




Correctly positioning timber

After cutting, the two halves of the timber will fall away from the saw blade, thus reducing the risk of kickback.



Correct positioning of timber



Example of bevel cutting with a saddle• The timber sits on to a saddle which holds the timber safely in place and at the

required angle while cutting.

• Provides a constant cutting angle for repeat jobs.

Images courtesy of the Health and Safety Executive, information sheet 16. Reproduced with permission.



Guarding a circular sawAll hand fed circular saws must be guarded in three ways:

• Guards fitted to the top and front of the saw above the table known as the crown guard.

• Riving knife fitted at the correct distance to the rear of the saw blade and the correct height above the machine table.

• Guards fitted below the machine table (usually formed by the main frame of the machine table).



Parts of a circular saw• Riving knife: prevents the timber

from binding during the cut and acts as a guard to the rear of the saw.

• Crown guard: guards the top of the saw blade.

• Extension table: keeps the person at the rear of the machine away from the saw blade.

• Extraction pipe: controls the dust from the saw and takes it to a collection unit.




Positioning of extension table

When sawing large pieces of timber it is essential for safety that the work piece is supported.

If an assistant is employed to remove cut pieces at the out feed side of the machine, the table should extend so that the delivery end is at least 1200mm from the saw centre.



Positioning of the crown guard



Positioning for blades less than 600mm in diameterThe riving knife should go to within 25mm of the top of the saw blade on saw blades less than 600 mm diameter.



Positioning for blades more than 600mm in diameter• The riving knife must match the saw blade at the rear of the saw.

• It must be curved to match the profile of the saw blade in use.

• The riving knife should be large enough to extend at least 225mm above the table for saw.



Safety delivery aidsPush stick and spike to be used on the last 300mm of the cut



Video on safe working practiceVideo on using a circular rip saw: www.hse.gov.uk/woodworking/ripsaw.htm

Video on using a crosscut saw: www.hse.gov.uk/woodworking/crosscut.htm

http://www.hse.gov.uk/woodworking/ripsaw.htm

http://www.hse.gov.uk/woodworking/crosscut.htm



Faults found with circular sawsAction required when identifying a fault with any circular saw:

• Stop and isolate machine immediately.

• Put a warning sign on the machine warning ‘Do not use. Faulty and dangerous machine’.

• Report faulty machine to your supervisor straightaway.



Examples of faults found with circular sawsFault

• Missing or damaged guards.

• Unable to correctly position guards.

• Incorrectly positioned riving knife.

• Missing out feed table when long lengths are to be cut or when a out feed worker is used.

• Damaged or blunt tooling.

Action required

• Repair and position correctly.

• Do not operate saw until guard can be positioned – maintenance could be required to free movement.

• Select suitable size and correctly position.

• Fit correct size out feed table.

• Remove and fit correct size tooling.



Any questions?

l2 bench joinery unit 211 power point presentation 1

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