TIMBER JOINERY APPLIED TO FURNITURE by LoyWeiWin

PROTOTYPE I 21st August - 30th August

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 I, Wood joinery applied to furniture, 2017.

1.1. PROTOTYPE I

Design and construction period, 21st August - 30th August Design Concept / Inspiration: • The design concept behind this prototype is mainly driven by Formstelle, Morph Bar Stool. • The prototype design was meant to be a simple mounting system where pieces can be lock into place and easily be disassembled and reassembled. • In term of ergonomics, the large backrest area is able to accommodate wide ranges of body size. Weight:

Dimensions: (refer to appendix A)

• 6.13 kg.

• 400 mm (W) x 290mm (D) x 920mm (H)

Materials: • Frame: 17mm CNC plywood and dressed recycled solid timber. • Seat and back: 1 layer of 1.5mm veneered plywood.

SEAT: (TRAIL)

STRECHER

PLYWOOD FRAME

Construction process: PART A.1

PART A.2

PART A.3

PART C.1

Cut stool components using CNC router. 1 hour

Retrieved components using chisel & hammer. 10 minutes

Glue stool frame using PVA adhesive. 10 minutes (18 hours curing time)

Cut lap joint using handsaw and chisel. 20 minutes

PART B.1

PART B.2

PART B.3

PART C.2

Select suitable solid timber 5 minutes

Dressing solid timber using thicknesser 15 minutes

Cut solid timber into length using drop saw. 10 minutes

Cut domino slot using domino joiner. 5 minutes

PART -D.1

PART -D.2

Measure 400 x 600mm cardboard 2 minutes

Kerf cutting the cardboard using knife 5 minutes

PART C.3 Glue and clamp all components till adhesive is fully cure. 10 minutes (18 hours curing time)

working with

VENEER SEAT

trail PART D.1

PART D.2

PART E.1

PART F.1

Measure 400 x 600mm plywood veneer 5 minutes

Cut veneer using table saw 15 minutes

Staple plywood veneer with staple gun. 20 minutes

Final clean up. 20 minutes

Figure 1.1.1: Overall construction workflow of prototype I.

Fabrication Duration:

General Comment:

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

: 80 : 30 : 35 : 7 : 40 : 20

Total production duration

: 212 mins + 36 hrs curing time

mins + 18 hrs curing time mins mins + 18 hrs curing time mins mins mins

39 hours 32 mins (include curing time)

The group manage to split the workload, allowing the team to carry several tasks at the same time. Besides that, the group took full advantage of using CNC router machine to increase the speed of production. However, an additional half an hour was spent on trying the “kerf” cutting methods before resorting to the original plan of stapling the plywood veneer seat onto the frame. Wood Joinery applied to furniture /

CONSTURCTION SEQUENCES

Design and construction period, 21st August - 30th August

B C

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. c. Saw carefully along stool structure to make space for half lap joint and housing joint later.

a. Both frame structures are connected by domino joint. PVA adhesive applied throughout the surface to further strengthen the joinery.

TECHNICAL CHANGE: a. Four domino dowels are used for each frame structure to increase the strength of the joineries during the production period instead of one domino dowel as the diagram illustrated.

a. Frame structures and seating supporting element are connected through key mortise and tenon joint. b. The stretcher is connected through half lap joinery. c. Backrest and supporting seat element is connected through domino joints.

a. Sand down the edge of the footrest with a sanding tool. b. Connect the footrest to the stool through a half lap joint. c. The wedges is inserted in the mortise and give a few taps with a hammer.

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

TECHNICAL CHANGE: TRIAL: Initially, the group agree upon to do kerf cutting on the plywood, but we realised that the 1.5mm plywood sheet is easily bended with small amount of force and stapled it on the stool frame with nail gun.

Wood Joinery applied to furniture /

1.1.2

1.1.3

1.1.4

1.1.5

Figure 1.1.2: Select suitable solid timber pieces for footrest, backrest and strechers. Figure 1.1.3: Dressing timber pieces through thicknesser. Figure 1.1.4: Trimming solid timber pieces to suitable length using mitre saw. Figure 1.1.5: Cutting a lap joint with handsaw and chisel.

1.1.6

1.1.7

1.1.8

1.1.9

Figure 1.1.6: Cutting stool frame using a CNC machine. Figure 1.1.7: Retrieved furniture parts from the CNC template. Figure 1.1.8: Apply PVA adhesive throughout the surfaces. Figure 1.1.9: Clamp all components till the adhesive is fully cure.

Wood Joinery applied to furniture /

1.1.10

1.1.12

1.1.11

1.1.13

Figure 1.1.10: Cutting dominos slot using a domino joiner. Figure 1.1.11: Connect stool modules together. Adhesive used to further strengthen the joineries. Figure 1.1.12: Clamp stool modules for a day to ensure the PVA adhesive is fully cure. Figure 1.1.13: Dry-fitting all stool parts before connect every parts together.

1.1.14

1.1.15

1.1.16

1.1.17

Figure 1.1.14: Trial: Kerf cutting on 400mm x 600mm cardboard. Figure 1.1.15: Trial: Testing out different options. Figure 1.1.16: Cutting 1.5mm plywood sheeting through table saw. Figure 1.1.17: Staple 1.5mm plywood sheeting on top of the stool frame with a staple gun.

Wood Joinery applied to furniture /

2 7

4 7

Figure 1.1.18: Prototype I - Exploded diagram.

LEGENDS: 1 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 I - (CNC template issue date: 24th August 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 : 0.858m2 Stool components : 0.379m2 Waste allowance : 0.261m2 Total plywood area (cut) : 0.640m2 Total wastage Material Efficiency

PLYWOOD FRAME

: 0.218m2 : 74.6%

CONSUMPTION COST - CALCULATION: 17mm plywood (2.40m x 1.20m) : 60.00 Plywood sheet area (1.75m x 0.49m) : 18.00 CNC Router (per session) Number of session Total session cost

: 10.00 :1 : 10.00

Total production cost

AUD AUD (rounded) AUD AUD

28.00 AUD

VENEER SEAT

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

: 34.70

AUD AUD (rounded) AUD

AUD (per product)

Comment and observations: The material recovery rate achieved 74.6 percent, however the efficiency can be increase by reducing the length of the backrest (CNCroutersource, n.d.). Hence reduce the total area of plywood sheet and indirectly reduce the manufacturing costs.

SCALE @ 1:8

Figure 1.1.19: CNC template layout - Prototype I. Wood Joinery applied to furniture /

End of the report. Thank you.