TIMBER JOINERY APPLIED TO FURNITURE by LoyWeiWin

PROTOTYPE II 11th September - 20th September

This work is copyright. Apart from any use permitted under the Copyright Act 1968, no part may be reproduced by any process without the prior written permission of the user. Cover Image: Finished prototype II, Wood joinery applied to furniture, 2017.

1.2. PROTOTYPE II

Design and construction period, 11th September - 20th September Design Concept / Inspiration: • Prototype II is basically an improved version of the previous model. Subtle changes are made according to previous comment received by advisors and fellow colleague. • Major change in term of the overall design is the length of the backrest. The group decided to reduce the backrest in order reduce construction material used. Weight:

Dimensions:

• 5.42 kg.

• 400 mm (W) x 310mm (D) x 920mm (H)

Materials: • Frame: 17mm CNC plywood and dressed recycled solid timber. • Seat and back: 2 layers of 1.5mm veneered plywood.

PLYWOOD SEAT

STRECHER

PLYWOOD FRAME

Construction process:

PART A.3.1

PART A.1

PART A.2

Cut stool components using CNC router. 1 hour

Retrieved components using hand router. 5 minutes

Glue stool frame using foam glue. 10 minutes (20 minutes curing time) PART A.3.2 Insert dowel pins and trim excess using japanese pull saw blade. 10 minutes

PART C.1

PART C.2

Cut domino slot using domino joiner. 5 minutes

Glue and clamp all components till adhersive is fully cure. 10 minutes (18 hours curing time)

PART B.1

PART B.2

PART B.3

Select suitable solid timber 5 minutes

Dressing solid timber using thicknesser 10 minutes

Cut solid timber into length using drop saw. 10 minutes

PART D.1

PART D.2

PART E.1

PART E.2

PART F.1

Measure 400 x 600mm plywood veneer 5 minutes

Cut venner using table saw 15 minutes

Staple plywood veneer with staple gun. 20 minutes

Glue and clamp additional plywood veneer till adhersive is fully cure. 10 minutes (18 hours curing time)

Final clean up. 10 minutes

working with

Figure 1.2.1: Construction workflow of prototype II.

Fabrication Duration:

(refer to figure 2.2.2.1)

Plywood frame Strecher and backrest Cut lap joint, domino and glue Venner seat Clean up

: 85 : 25 : 15 : 50 : 10

Total production duration

: 185 mins + 36 hrs 20 mins curing time

mins + 20 mins curing time (foam glue) mins mins + 18 hrs curing time (PVA glue) mins + 18 hrs curing time (PVA glue) mins

39 hours 25 mins (include curing time)

General Comment The group decided to use domino joints for all joinery instead of half lap joint to reduce the production time. Also, the group used foam glue to speed up the curing process. However, this process tends to leave residue and stain on the plywood. Additional layer of veneer is added to the seat for extra support. However, this caused an extra day for the adhesive to be fully cured. Wood Joinery applied to furniture /

CONSTURCTION SEQUENCES

Design and construction period, 11th September - 20th September

a. Glue both frame structures and clamp together until the glue is fully cured. b. Ensure both structures are at perfect alignment with one another.

a. The domino joints might have similar characteristics with dowelled joint but due to lager surface area, domino joints able to provide a stronger grip across the stool frame. Adhesive can be applied to further strengthen the joinery.

a. All timber component to further strengthen t

ts are connected by domino joint. PVA adhesive applied to all joinery surface the joineries.

a. 1.5mm bended plywood is staple on top the stool frame.

TECHNICAL CHANGE: a. Another piece of bended plywood is glued on top the stool frame and clamped until the adhesive is fully cure. This technique not only provide another additional support for the seating area but also cover up any trace of the nail gun, provide a better finish result.

Wood Joinery applied to furniture /

1.2.2

1.2.3

1.2.4

1.2.5

Figure 1.2.2: Cutting cut tabs or bridges using hand router. Figure 1.2.3: Applying foam glue throughout the stool surfaces. Figure 1.2.4: Insert dowel pins into predrill holes before foam glue is set to dry. Figure 1.2.5: Clamp stool modules until the adhesive is fully cure.

Wood Joinery applied to furniture

1.2.6

1.2.7

1.2.8

1.2.9

Figure 1.2.6: Trimming out the excess dowel pins using japanese pull saw blade. Figure 1.2.7: Sanding stool modules before connecting all components. Figure 1.2.8: Clamping stool frame until adhesive is fully cure. Figure 1.2.9: Clamping 1.5mm plywood sheet on top of stool frame.

Wood Joinery applied to furniture /

1.2.10

1.2.11

1.2.12

1.2.13

Figure 1.2.10: Masking tape along the stool edges to prevent excess glue from dripping onto the surfaces. Figure 1.2.11: Adding another 1.5mm plywood sheet to provide additional support to the seat. Figure 1.2.12: Clamp the plywood sheet on top of the seat until adhesive is fully cure. Figure 1.2.13: Trim off excess plywood seat.

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2 7

Figure 1.2.14: Prototype II - Exploded diagram.

LEGENDS: 1 2 x 1.5mm plywood sheet. 2 Solid timber backrest. 3 Seat supporting element type 1. 4 Backrest supporting element. 5 Solid timber stretcher. 6 Solid timber footrest. 7 CNC plywood stool frame.

MATERIAL CONSUMPTION:

Prototype II - (CNC template issue date: 13th September 2017)

LEGENDS: A1 B1 / B2 / B3 / B4 C1 / C2 / C3 / C4

- Plywood supporting element. - Stool frame type B. - Stool frame type C. - 20mm wastage allowance. (8mm rougher used)

MATERIAL EFFICIENCY - CALCULATION: Plywood sheet area : 0.885m2 Stool components : 0.377m2 Waste allowance : 0.280m2 Total plywood area (cut) : 0.657m2 Total wastage Material Efficiency

PLYWOOD FRAME

: 0.228m2 : 74.2%

PRODUCTION COST - CALCULATION: 17mm plywood (2.40m x 1.20m) : 60.00 Plywood sheet area (1.77m x 0.50m) : 18.40 CNC Router (per session) Number of session Total session cost

: 10.00 :1 : 10.00

Total production cost

AUD AUD (rounded) AUD AUD

28.40 AUD

VENEER SEAT

1.5mm plywood (2.40m x 1.20m) : 80.00 Plywood sheet area (0.40m x 0.60m x 2) : 6.70 Total material cost : 13.40 Total manufacturing costs

: 41.80

AUD AUD (rounded) AUD

AUD (per product)

Comment and observations: In term of material recovery rate, it was slightly lower than expected due to the fact that most of the stretcher and footrest were produced manually and also leaving behind a substantial watse on the CNC cuts. Moreover, the manufacturing cost of prototype II increase significantly because of the 2 additional 1.5mm plywood sheet that was used to improve the overall strength of the veneer seat.

SCALE @ 1:8

Figure 1.2.15: CNC template layout - Prototype II. Wood Joinery applied to furniture /

End of the report. Thank you.