Components	Task 3
Task
Characteristics of surface
Suitable surface preparation method
Tools and equipment
Material requirements
WHS requirements

Work Instructions and specifications

Task:

To prepare internal and curves surface of a solid hard wood stool seat.

Work specifications:

• Stool dimensions:
  • Diameter of the stool seat - 30 cm
  • Height of the stool - 35 cm
  • Thickness of stool seat - 2 cm
• Surface material - Solid hardwood
• Surface characteristics:
  • Wood Type - Pine with integrate grain-patterns
  • Surface Condition - Grain variations and rough areas
  • Imperfections - Knots and grain swirls
  • Moisture Content - 8% (kiln-dried)
  • Recommendation: sanding sealer, and a finish
• Surface preparation technique - Sanding (manual sanding)
• Surface coating material - 2 coats of Shellac

Materials used:

• Wood filler
• Shellac

Tools and equipment used:

• Sanding blocks-Essential for manual sanding to provide even pressure across the surfaces and edges, especially useful for achieving a smooth finish on curved areas.
• Wood filler - To fill any cracks, holes, or imperfections in the hardwood before sanding.
• Tack cloth -Necessary to wipe down the wood after sanding, ensuring it is free of dust and debris before applying the finish.
• Brushes - Needed for applying shellac.
• Liquid containers - Useful for holding and mixing shellac before application, ensuring it remains clean and free from contaminants.
• Steel wool/ Scourers - For smoothing the shellac between coats and achieving a fine finish. Steel wool is particularly effective for buffing shellac to a high gloss.
• Cabinet scrapers - Can be used instead of or in addition to sanding blocks for fine-tuning the surface preparation on hardwood, especially effective for removing any remaining high spots or minor imperfections after initial sanding.
• Clamps - Useful for securing the stool while working, particularly if parts of the stool need to be held steady during filling or detailed sanding

Work instructions:

Step 1 - Inspection and cleaning

• Examine the stool internal surface for any visible cracks, splinters, or rough patches. Identify areas that need filling or special attention.
• Wipe the wood down with a dry cloth to remove any dust or debris that could interfere with sanding and finishing.

Step 2 - Apply wood filler

• Use wood filler to address any cracks or holes in the wood. Apply the filler using a putty knife, pressing it firmly into the imperfections.
• Allow the filler to dry completely according to the manufacturer's instructions. This may take several hours.
• Once dry, sand the filled areas smoothly with a fine-grit sandpaper to ensure they are flush with the surrounding wood surface.

Step 3 - Sand the surface

• Start with a medium-grit sandpaper (around 120 grit) attached to a sanding block. Sand the entire internal surface, focusing on achieving a uniformly smooth area, especially over the filled sections.
• Move to a finer grit sandpaper (180-220 grit) to refine the surface. Ensure you sand along the grain of the wood to prevent scratches.
• Use cabinet scrapers for any hard-to-reach areas or to achieve finer detail on the curved edges. This tool helps obtain a more precise finish.
• Use a tack cloth or a soft brush to remove all sanding residue from the wood. The surface must be completely clean before applying shellac.

Step 4 - Apply shellac

• Stir the shellac gently in a liquid container. Avoid shaking to prevent bubbles.
• Apply a small amount of shellac to an inconspicuous area to test for colour and finish.
• Apply the first coat of shellac using a high-quality natural bristle brush. Brush evenly along the grain of the wood. Cover all surfaces smoothly and avoid over-application to prevent drips.
• Allow the shellac to dry completely, which typically takes a few hours depending on humidity and temperature.

Step 5 - Sand between coats

• After the first coat has dried, lightly sand the surface with very fine steel wool (000 grade). This process helps to smooth any raised fibres and prepares the surface for the next coat.
• Wipe the surface again with a tack cloth to remove all dust from sanding.

Step 6 - Additional coat

• After the first coat is fully dry and the surface is prepped, apply a second coat of Apply a second coat of lacquer, if required.
• Allow ample time for the final coat to cure completely.

Step 7 - Final inspection and clean-up

• Examine the stool seat internal surface and curved surfaces in good light for any runs, sags, or imperfections
• Clean the brushes with mineral spirits or alcohol, and properly store or dispose of used materials

Quality requirements

• The stool's surfaces, both internal and curved, must be uniformly smooth without any rough spots or uneven sanding marks
• Wood filler should be applied seamlessly, with no visible edges or discrepancies in texture or colour
• The shellac application should be even across all areas with no drips, streaks, or bubbles
• The shellac must adhere properly to the hardwood surfaces without peeling or lifting

Safety instructions

• Wear appropriate PPE
• Ensure the workspace is well-ventilated, especially when applying shellac, to avoid the build-up of fumes which can be hazardous to health.
• Handle shellac and other chemicals according to the manufacturer's instructions
• Store chemicals in a cool, dry place away from direct sunlight and heat sources to prevent degradation or combustion
• Be aware of the flammable nature of shellac and its solvents. Keep them away from open flames and sources of ignition
• Ensure all tools are maintained in good condition and used correctly.
• Check that sanding blocks and other manual tools are free of defects that could cause injury.