1
6
2
3
6
4
2
5
Figure I: Iteration 2.2 - Exploded diagram.
LEGENDS: 1 2 x 1.5mm plywood sheet. 2 CNC supporting element type 1. 3 CNC supporting element type 2. 4 CNC plywood stretcher. 5 CNC plywood footrest. 6 CNC plywood stool frame.
MATERIAL CONSUMPTION:
Iteration 2.2 - (CNC template issue date: 24th September 2017)
LEGENDS: A1 / A2 / A3 / A4 B1 C1 / C2 C3 C4
- Stool frame type A. - Stool frame type B. - Plywood stretcher. - Plywood lower rail. - Plywood footrest. - 20mm wastage allowance. (8mm rougher used)
VENEER SEAT
PLYWOOD FRAME
1
2
8MM ROUGHER
Figure II: Iteration 2.2 - CNC layout template.
SCALE @ 1:8
Est. Consumption Cost: (Raw material cost + CNC session cost) 17mm plywood (2.40m x 1.20m) : 60.00 AUD Plywood sheet area (1.29m x 0.56m) : 15.00 AUD (rounded) CNC Router (per session) Number of session Total session cost
: 10.00 :1 : 10.00
AUD AUD
Total production cost
: 25.00 AUD
1.5mm plywood (2.40m x 1.20m) Plywood sheet area (0.40m x 0.60m x 2) Total material cost
: 80.00 : 13.30 : 13.30
AUD AUD (rounded) AUD
Total manufacturing costs
: 38.30
AUD (per product)
Est. Material Efficiency: (CNC router machine) Plywood sheet area : 0.752m2 (refer to figure III) Stool components Waste allowance Total plywood area (cut)
: 0.326m2 : 0.279m2 : 0.605m2
Total wastage Material Efficiency
: 0.147m2 : 80.5%
ITERATION 2.2: (refer appendix C for complete list 1
2 Puzzle Joint
a. Apply PVA glue on each male and female frame modules and clamp the structure together. b. Dowel pieces are inserted into predrill holes to ensure both modules are in perfect alignment. c. Excess dowel pieces have been trimmed off by japanese pull saw blade and sanded down. 3
a. Structures are connected through dowel joint. PVA adhesive are applied throughout the surfaces to further strengthen the joinery. b. Dowel pieces are inserted into predrill holes to ensure both modules are in perfect alignment.
4
B
B B
B
A
a. The footrest and supporting elements are connected to the stool structure through domino joints B and dowel joints A .
a. 1.5mm bended plywood is staple on along the stool frame. Additional plywood is then glue on top of the stapled plywood to provide additional support.
ADDITION(S): • Additional supporting elements could be added underneath the veneer seat to provide extra support to the seat.
ALTERNATIVE SOLUTION(S): • The veneer seat can be formed using jigs to ensure a greater level of accuracy before attached to the seat. This method could also speed up the production process in the long run. • Vacuum veneering or steam bending techniques could be explore if the workshop equip these equipments. (Finewoodworking, 1989)
Figure III: Construction sequences of iteration 2.2.