A chair for Emily Carr and her dog Koko

(wo)MAN’S BEST FRIEND

A CHAIR FOR EMILY CARR AND HER DOG KOKO

David Donnelly - 20411299 Natalie Krakovsky - 20427441

CONTENTS

4 8 12 18 22

MANIFESTO/ CLIENT RESEARCH/ DESIGN PARAMETERS PRECEDENT IMAGES

DESIGN DEVELOPMENT DRAWINGS

FINAL DRAWINGS/ WORKING DRAWINGS PERSPECTIVE DRAWINGS/ ASSEMBLY PROCESS

NESTING DIAGRAM/ COMPONENT DRAWINGS PHOTOGRAPHED/ DOCUMENTED FINAL CONSTRUCTION CONSTRUCTION PROCESS/ PROTOTYPING MATERIAL LIST/ COMPONENT MANIFESTO

FINAL CALCULATIONS

REFLECTION

28 32 36 44 46 60

4

MANIFESTO/ CLIENT RESEARCH/ DESIGN PARAMETERS

MANIFESTO/

Emily is a great Canadian artist who loved her pets, particularly her dogs. Emily Carr painted Canadian landscapes in a modern and poetic way. Our chair design will aim to capture Emily Carr’s essence, not only through her incredible artistic talent, but through her love for her dogs, particularly Billy. We want to design and build a chair that Emily Carr would be able to read, write and paint along side her most loyal companion, her dog Billy. This would be especially beneficial since she worked predominately in oil and paper giving her freedom to work outside. The chair will be built to be set within the great Canadian wilderness at a cottage or an artists post. Our design will look to incorporate natural materials to create a relaxing escape to think deeply for both the Emily and Billy.

5

CLIENT RESEARCH/

6

DESIGN PARAMETERS Since the chair is design not only for a person, but for a dog aswell, there were a few restrictions in how the chair could be designed.

1 We designed a patio chair. Therefore, comfort was a major concernfor both the owner and his/her dog. Using fabric in the palces where the dog and the person sits was the solution.

2 The dog portion needed to be elevated off the ground. As a dog ages and health

problems arise, cement and other cold/hard surfaces can irritate the dog. Therefore,we elevated the plateform slightly off the ground.

3 The portion for a dog needed to have a slight bounce to it to increase comfrot further.

Therefore, the form work of the wood structure bends in a way that fores the fabric to becomealmost bubble like.

4 We wanted to limit the amount of wood members that penetrate the dogs sitting area

because a dog needs space to site upright, lie down and lift his/her head. Therefore, the form of the chair involved a solid member that transferred the weight of the seat to either end of the chair leaving the space for the dog free and open. For further information on this visit the final calculation section.

5 We wanted to limit the amount of wood members that penetrate the dogs sitting area

because a dog needs space to site upright, lie down and lift his/her head. Therefore, the form of the chair involved a solid member that transferred the weight of the seat to either end of the chair leaving the space for the dog free and open. For further information on this visit the final calculation section.

6 Sun need to penetrate trough too the dogs seat, but there still should be the ability to

have the area shaded at certain times of the day. Using Upholstery instead of wood was a solutions to this.

7 Emily Carr loved literature and art. Therefore, we wanted to create a portion that could be used to rest a book or a sketch pad enabeling her to draw/write/read while in her chair.

8 There are many structural restrictions withing the chair that were solved by making stronger solid sections that could withstand tension.

7

8

PRECEDENT IMAGES

PRECEDENT IMAGES 1

3

9

2

5

4

10

6

6

5

These precedents inspired the simple form we designed; a seat on top for a person to sit and an area underneath that can be a dog bed.

1 https://www.pinterest.com/J0hnMoore/dog-houses/ 2 http://www.remals.com/attractive-pet-house-design-ideas/ 3 http://www.citylab.com/design/2012/10/behold-dog-house-sofa/3640/ 4 http://www.citylab.com/design/2012/04/rocking-chair-your-cat-or-dog/1843/ 5 http://www.designboom.com/design/cat-shelters-architects-for-animals-fixnation-los-angeles- 09-16-2014/?utm_campaign=daily&utm_medium=e-mail&utm_source=subscribers 6 http://www.dezeen.com/2014/06/03/paul-loebach-launches-peg-chair-during-nyc-design-week/

11

12

DESIGN DEVELOPMENT DRAWINGS

PHASE 1

Early in the design process we envisioned our form of seating to be in the style of a bench. Large enough to seat two people and have a pull out compartment for the dog. The compartment would give the dog the ability to lay out in the sun beside his owner or underneath the bench in the shade, with the language of a dog house.

13

PHASE 2

The second phase shared a similar principle to the first, but was a simpler design. The idea was still for a bench, but part of the bench transformed (Figure1) to allow a stronger connection between the dog and the owner.

14

FIGURE 1

1 Two person bench

2 Remove seat

15

3 Slide piece into bench

4 A seat for you and your dog

16

PHASE 3

For our final phase we took inspiration and ideas from the first iterations, but reimagined how the chair would be used.

We felt the bench was too bulky so we narrowed it down to simply a chair for man and his best friend. It became less “solid� to allow for light to penetrate beneath the chair yet it still allows for shade during the hotter portions of the day. This eliminated the need to have removable parts. A writing desk was also added to include Emily Carr’s love for literature and art.

17

18 FINAL DRAWINGS/ WORKING DRAWINGS

FINAL DRAWINGS 33

402

1 FRONT ELEVATION

615

19

610

2 SIDE ELEVATION

381

533

459

489 20

33

3 SECTION

323

194

232

43 418 21

116

22

PERSPECTIVE DRAWINGS/ ASSEMBLY PROCESS

PERSPECTIVE DRAWINGS/

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24

25

The chair is not solid wood we designed it so that it could be upholstered. Creating a more comfortable chair for relaxing. These are axonometric drawings in its bare form.

26

ASSEMBLY PROCESS

The chair was designed so that we could use a CNC machine. Each piece of the chair is made of 11 mm plywood. The three pieces are glued together and then left to dry using clamps. The male joint was made slightly larger then the female joint so we would be able to shave it down using the router and the band saw, after the glue has dried. This gives us control over how tight the joint is. The pieces then are hammered into one another with a rubber mallet. The joints used throughout the chair are mortise and tenon.

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28

NESTING DIAGRAM/ COMPONENT DRAWINGS

NESTING DIAGRAM/ 1 SEAT PIECE

2 BASE PIECE

29

COMPONENT DRAWINGS 33 22

PIECE A x2

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PHOTOGRAPHED/ DOCUMENTED FINAL CONSTRUCTION

33

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35

36

CONSTRUCTION PROCESS/ PROTOTYPING

CONSTRUCTION PROCESS/ 1 DESIGN CHAIR /

5 HAMMER THE

2 CNC PIECES FOR

6 APPLY

3 SAND ROUGH

7 COMPLETED CHAIR

PROTOTYPE / CREATE AUTOCAD FILES FOR CNC MACHINE

CHAIR

EDGES / GLUE AND CLAMP SETS OF THREE TOGETHER

4 ROUTER THE

EDGES TO ACHIEVE A TIGHT MORTISE AND TENON CONNECTION

37

JOINTS TOGETHER

UPHOLSTERY WITH STAPLE GUN TO THE FRAME OF THE CHAIR

PROTOTYPING PHASE 1 - 1:5

38

PHASE 2 - 1:5

39

40

PHASE 3 - 1:5

41

42

PHASE 4 - 1:2

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44

MATERIAL LIST/ COMPONENT MANIFESTO

MATERIAL LIST 1 PLYWOOD

TYPE: 1/2 inches 4x8 Sanded Fir Plywood AMOUNT: 4 sheets (2 were used) PRICE: $115 STORE PURCHASED: Home Depot 64% of final chair cost

2 CARPENTER’S GLUE

TYPE: LePage AMOUNT: 1 bottle PRICE: $16 STORE PURCHASED: Home Depot 8% of final chair cost

3 UPHOLSTERY

TYPE: 2 inches seat belt webbing AMOUNT: 28 yards PRICE: $32 STORE PURCHASED: Lens Mill Store 28% of final chair cost

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46

FINAL ANALYSIS CALCULATIONS

COMMON LOADS/ REACTIONS A

1 kN

C

0.5 kN

D

E

G H1

H

B

F

V2

V1

A

1 kN

C

0.5 kN

D

E 1 kN

G H1

B

F

V2

47

H

V1

LEGEND

STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

CRITICAL SECTION The critical section is around joint A. This joint carries the highest moment load and is crucial for the structure of the chair. We determined this point to be the critical section over joint E or joint H because it is here that both the vertical and lateral forces act together in the highest magnitude, creating more stress on this joint than any other. V1 is multiplied by 480mm (horizontal distance away form joint) and H1 is multiplied by 208mm (vertical distance away from joint). We also considered this to be the critical section because of our design in the construction of the chair. By building the main “beam� member of the chair, (member ACDE) from a solid piece of wood, we reduced the stress and moment experienced at points C and D considerable, however, this stress is transferred more to joint A than E. We analyzed a number of joints to be sure joint D was the critical section. This becomes the critical section over joint C because the applied horizontal force is in line with joint C and therefore is negligible in the moment calculation; in addition the applied vertical force is only multiplied by 276mm (distance away from joint) in comparison to the 480mm in the case of joint D. Joint H experiences a smaller moment than joint D because the larger vertical force is located closer horizontally to the joint and therefore creates a smaller moment.

Analyzing the chair from the east elevation we see a number of areas that experience stress though none that could be considered the critical section because this chair section is shorter and built with fewer joints. However an interesting area we wanted to analyze was the vertical force experienced on joint A. The force from a person leaning back could cause uplift, and stress at this joint. We analyzed this section with a 1 KN force acting vertically and a 0.5 KN force acting horizontally applied to the middle section of the chairs back. What we found was there was an uplift force but only of 0.083 KN which told us that it was something to be considered in the design but was very manageable.

48

NARRATIVE The structure chosen is completely reflective of the design intent.

That is, a chair for a person, a chair for a dog, and a flat surface for writing/art. The structure bends and forms in the most direct way to accommodate these purposes. A place for a dog to rest just inches from the ground which allows for easy access of the dog and a comfortable place above the cold ground which causes great discomfort for older dogs with arthritis. The seat itself is reclined five degrees and uses a tensile fabric to hold the user while they wright, draw or read from the surface positioned beside the chair. The chair is intended to be used outdoors, on a patio, a place Emily Carr was fond of. The fabric easily dries when wet, provides a comfortable seat for both users and provides ample shading for the dog. Wood was chosen for its cost, workability, aesthetics and connection to nature, which was the focus of much of Emily Carr’s work. The structure is composed of three basic parts, which are the two sides, which transfer the vertical loads to the ground, the lateral bracing pieces, which, connect the two sides, and finally the seat, which carries the person and rests on the lateral members. The structural design started with many straight pieces with complex joinery and eventually developed into edited and simplified pieces to render the most efficient use of material, and the strongest structure possible. The most distinctive and unconventional part of the structure is the lateral bracing which forms two right angles, allowing space below for a dog sitting tall, and space above as a writing surface. Multiple iterations of this member held together with joinery resulted in unsecured and failed structures. This needed to resist the largest forces acting on the chair and the most structural and simplest of solutions was to build this piece solid.

The joints used throughout the chair are mortise and tenon. These joints were used because of their strength and because they are easily hidden. The construction of the chair involves 3 pieces of 11mm plywood glued together with the central piece containing the male joints. These pieces glued together give the chair its cross sectional strength.

49

BASE REACTION *Dog excluded from calculation 1. Sum of the horizontals ΣFx = 0 H1 - 0.5 kN = 0 H1 = 0.5 kN 2. Moment around B ΣMB = 0 (0.5 kN)(0.432 m) + (V1)(0.61 m) - (1 kN)(0.409 m) = 0 0.216 kNm + V1(0.61 m) = 0.409 kNm V1(0.61 m) = 0.193 kNm V1 = 0.32 kN 1 kN A

C

3. Sum of the verticles

0.5 kN

D

ΣFy = 0 V1 + V2 = 0 V2 = 1 kN - V1 V2 = 1 kN - 0.32 kN V2 = 0.68 kN

E

G

H

H1 = 0.5 kN B

F

V1 = 0.32 kN V2 = 0.68 kN H1 = 0.5 kN

V2 = 0.68 kN

V1 = 0.32 kN

Therefore the base reaction calculations are 0.32 kN for V1, 0.68 kN for V2 and 0.5 kN for H1.

A

C

D

1 kN

0.5 kN 50

BASE REACTIONS *Dog included in calculation 1. Sum of the horizontals

A

C

ΣFx = 0 H1 - 0.5 kN = 0 H1 = 0.5 kN

1 kN

0.5 kN

D

E

2. Moment around B G H ΣMB = 0 H1 = 0.5 kN Bm) - (1 kN)(0.409 m) - (0.045 F (0.5 kN)(0.432 m) + (V1)(0.61 kN)(0.2 m) - (0.045 kN)(0.41m) = 0 0.216 kNm + V1(0.61 m) - (0.409 m) - (0.009 m) - (0.018 m) = 0 V1(0.61 m) = 0.22 kNm V2 = 0.68 kN V1 = 0.32 kN V1 = 0.36 kNm

V1 = 0.36 kN 3. Sum of the verticles ΣFy = 0 V1 + V2 - 1kN - 0. 045 0. 045 = 0 V1 + V2 - 1.09 kN = 0 V2 = 1.09 kN - V1 V2 = 1.09 kN - 0.36 kN V2 = 0.73 kN V1 = 0.36 kN V2 = 0.73 kN H1 = 0.5 kN

A

C

1 kN

0.5 kN

D 0.045 kN

G

H1 = 0.5 kN B

E 0.045 kN

H F

V2 = 0.73 kN

V1 = 0.36 kN

Therefore the base reaction calculations are 0.36 kN for V1, 0.73 kN for V2 and 0.5 kN for H1. The dog is so light it is almost negligible.

51

H1 = 0.5 kN

FREE BODY DIAGRAM MEMBER AB V2 = 0.68 kN

LEGEND C

A

1 kN

*Dog excluded STANDARD JOINTin calculation

C

WELDED PIN 0.5 kN 1. STRUCTURAL Sum of theELEMENTS verticles NOT D CONSIDERED ELEMENTS E PIN ROLLER ΣFy = 0 LOADS VAREACTIONS - V2 = 0 G B

VA = V2 VA = 0.68 kN

G

H F H1 = 0.5 kN

2. Moment around A

LEGEND D

B

V1 = 0.32 kN

1 kN

0.5 kN

E STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS 0.045 kN 0.045 kN NOT CONSIDERED ELEMENTS PIN ROLLER H LOADS REACTIONS F

ΣMA = 0 V2 = 0.73 kN V1 = 0.32 kN (0.5 kN)(0.615 m) - (HG)(0.515 m) = 0 0.3075 kNm - (HG)(0.515 m) = 0 VA = 0.73 kN 0.3075 kNm = (HG)(0.515 m) HG = 0.6 kN HA = 0.1 kN

V2 = 0.68 kN

V1 = 0.36 kN

A

kN 3. Sum of the1 horizontals C ΣFx = 0 HG - HA - 0.5 kN = 0 HA = HG - 0.5 kN D HA = 0.6 kN - 0.5 kN E HA = 0.1 kN 0.045 kN 0.045 kN

0.5 kN

G G

VA = 0.68 kN HG = 0.6 kN HA = 0.1 kN

H

HG = 0.6 kN

B

H1 = 0.5 kN F

V2 = 0.68 kN

Therefore the reactions are 0.68 kN for VA, 0.6 kN for HG and 0.1 kN V1 = 0.36 kN for HA.

V2 = 0.73 kN

VA = 0.73 kN

VA = 0.68 kN HA = 0.1 kN

A

HA = 0.1 kN

52

E

MEMBER AC

0.045 kN

0.045 kN

G

*Dog excluded in calculation

H1 = 0.5 kN

B

F

VA = 0.68 kN HA = 0.1 kN

V2 = 0.73 kN

VA = 0.73 kN

1. Sum of the verticles ΣFy = 0 VA - VC = 0 VC = VA VC = 0.68 kN

A

2. Sum of the horizontals ΣFx = 0 HA - HC = 0 HC = HA HC = 0.1 kN VC = 0.68 kN HC = 0.1 kN

H

HA = 0.1 kN

G

HG = 0.6 kN

B

H1 = 0.5 kN

V2 = 0.68 kN

Therefore the reactions are 0.68 kN for VC and 0.1 kN for HC. VA = 0.68 kN HA = 0.1 kN

A

HA = 0.1 kN HC = 0.1 kN

LEGEND

VA = 0.68 kN

STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

53

C VC = 0.68 kN

V1 = 0.36 k

MEMBER CD *Dog excluded in calculation

HG = 0.6 kN

B

H1 = 0.5 kN

VC = 0.68 kN HC = 0.1 kN 1. Sum of the verticles ΣFy = 0 VC - VD = 0 VD = VC VD = 0.68 kN

G

V2 = 0.68 kN

VA = 0.68 kN HA = 0.1 kN

2. Sum of the horizontals ΣFx = 0 HC - HD = 0 HD = HC HD = 0.1 kN

A

HA = 0.1 kN HC = 0.1 kN

VA = 0.68 kN

C VC = 0.68 kN

VD = 0.68 kN HD = 0.1 kN Therefore the reactions are 0.68 kN for VD and 0.1 kN for HD.

HC = 0.1 kN C

LEGEND

STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

VC = 0.68 kN HC = 0.1 kN

VC = 0.68 kN

D VD = 0.68 kN

HD = 0.1 kN

54

MEMBER DE H

F

*Dog excluded in calculation

8 kN

D

STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

V1 = 0.32 kN

VD = 0.68 kN HD = 0.1 kN 1. Sum of the verticles ΣFy = 10kN C 1 kN - VD + VE = 0 VE = 1 kN - VD 0.5 kN VE = 0.32 kN E

2. Sum0.045 of the horizontals kN ΣFx = 0 HD - HE = 0 HD = HE H HE = 0.1 kN

45 kN

F

VE = 0.32 kN HE = 0.1 kN

3 kN

V1 = 0.36 kN

Therefore the reactions are 0.32 kN for VE and 0.1 kN for HE.

3 kN A

1 kN

LEGEND

= 0.6 kN

55

8 kN

HD = 0.1 kN

STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS H1 = 0.5 kN REACTIONS

1 kN

C

D

1 kN

VD = 0.68 kN

D

HD = 0.1 kN

0.5 kN HE =E0.1 kN E VE = 0.32 kN

VD = 0.68 kN G B

V2 = 0.68 kN

H F

V1 = 0.32 kN

H

MEMBER EF F

V1 = 0.36 kN

*Dog excluded in calculation VE = 0.32 kN HE = 0.1 kN

1 kN VD = 0.68 kN

1. Sum of the verticles HD = 0.1 kN ΣFy = 0 D HD = 0.1 kN VE + V1 = 0 V1 = VE VD = 0.68 kN V1 = 0.32 kN

HE = 0.1 kN E VE = 0.32 kN

2. Sum of the horizontals ΣFx = 0 HH - HE - 0.5 = 0 HH = 0.5 + HE HH = 0.6 kN V1 = 0.32 kN HH = 0.6 kN

kN

Therefore the reactions are 0.32 kN for V1 and 0.6 kN for HH. Therefore the system is in equilibrium.

LEGEND

STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

VE = 0.32 kN

HE = 0.1 kN E VE = 0.32 kN

HE = 0.1 kN

HH = 0.6 kN H F

V1 = 0.32 kN kN

0.5 kN

56

MEMBER HG F

8 kN

V1 = 0.32 kN

*Dog excluded in calculation HH = 0.1 1 kN kN

C

1. Sum of the horizontals 0.5 kN ΣFx = 0 D HG - HH = 0 E HG = HH 45 kN HG = 0.045 0.6 kN kN H

Therefore the base reaction calculations are 0.6 kN for HG. Therefore F the chair is in equilibrium.

3 kN

V1 = 0.36 kN

3 kN

1 kN

1 kN VD = 0.68 kN

LEGEND

= 0.6 kN

8 kN

kN

57

8 kN

HD = 0.1 kN

STANDARD JOINT WELDED PIN STRUCTURAL ELEMENTS NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

D

HD = 0.1 kN

VD = 0.68 kN

HE = 0.1 kN E VE = 0.32 kN

LOADS REACTIONS

SHEAR AND BENDING MOMENT DIAGRAMS 1 kN

HA = 0.1 kN A

HE = 0.1 kN

V A = 0.68 kN

0.5 kN

E

VE = 0.32 kN

0.68 kN

0.68 kN

0.68 kN

0.68 kN

0 0.32 kN

0

SHEAR FORCE DIAGRAM

0.32 kN

HD = 0.1 kN

E

D

0 HD = 0.1 kN

0.32 kN

0.0698 kN

1 kN VD = 0.68 kN 0

0.32 kN

0.0698 kN

HE = 0.1 kN E VE = 0.32 kN

BENDING MOMENT DIAGRAM VD = 0.68 kN

= 0.1 kN

0.5 kN

58

V1 = 0.32 kN

MAXIMUM STRESS 1 kN

HA = 0.1 kN

A

LEGEND

kN

HE = 0.1 kN

V A = 0.68 kN

STANDARD JOINT WELDED PIN 0.5 kN STRUCTURAL ELEMENTS E NOT CONSIDERED ELEMENTS PIN ROLLER LOADS REACTIONS

0.5 kN

E

VE = 0.32 kN

H

*Dog excluded in calculation F

Section of Interest V1 = 0.36 kN

1. Moment around A ΣMA = 0 (0.1 kN + 0.5 kN)(0.15 m) - (0.32 kN)(0.61 m) + (1 kN)(0.175) - MA = 0 0.09 kNm - 0.1952 kNm + 0.175 - MA 1 kN = 0 *Note that we have written MA = 0.265 kNm - 0.1952 kNm M in the units of Nmm in this VD = 0.68 kN MA = 0.0698 kNm equation, rather than kNm, HE = 0.1 kN HD = 0.1 kN

D

Therefore the moment is 0.0698 0.1 kN for HD =kNm VD = 0.68 kN

so we had to multiply it by

1,000,000. It is critical that all E MA. in an equation use the E = 0.32 kN Vterms same system of units.

Maximum Bending Stress Calculation at Critical Section S = bd^2/6 S = (36)(36^2)/6 S = 7776 mm^3

M = 0.0698/2 kNm M = 0.0349 kNm The element is 36 mm x 36 mm b = 36 mm d = 36 mm 1 kN HD = 0.1 kN 59

VD = 0.68 kN

HE = 0.1 kN

σ = M/S σ = 34900 Nmm / (7776mm^3) σ = 4.5 MPa < σallow = 5 MPa This section is adequate!

60

REFLECTION

REFLECTION Our chair developed from countless sketches, digital models, two 1:5 scale models and one 1:2 scale model. This process of sketching, digital modeling and physical modeling allowed us to anticipate design problems and solve many issues before final construction. This process was extremely valuable to the final product however the final product was the only full scale, fully constructed iteration and so having completed it we have found a number of improvements and solvable design problems we faced with the final product.

Iteration 1: Iteration 1 was a 1:2 cardboard model of early design sketches. It was deemed unsatisfactory to our needs and proved a need for further design development.

Iteration 2: the second iteration was a 1:5 scale bass wood, laser cut model. We anticipated mortensen tenon joints would be the best solution for our chair and so designed this scale model with these joints. We found the joints worked well, though our major structural piece, the lateral member that supports the chair, which also happened to be our critical section, was not able to made from moment joints. It was far too weak and an unnecessary risk to keep this member jointed. We also found we could reduce the number of joints over all and increase stability. We would solve this in further iterations.

Iteration 3: The third iteration was a 1:5 scale bass wood, laser cut model. The third iteration solved the critical section by creating the member from one solid piece. And having the chair rest on it. In this iteration we also increased the thickness of the members and altered the design of the base. We would find a happy medium between member thicknesses and alter the base further in future iterations. We also decreased the number of jointed by flattening the chair section.

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Iteration 4: The fourth iteration was a 1:2 cardboard laser cut model. This Iteration combined all design solutions and was prepared as if it was the final product with all current design issues solved. Only minor differences appear in the final product.

Final product: The final product was made from CNC cut plywood sections glued together to achieve the desired cross section. Mortensen Tenon joints which were meticulously shaved down to achieve the perfect fit, needing to be hammered into place, neglecting the use of glue. Fabric was purchased and stapled to the chair for the upholstery.

Future iterations: having finally completed the finished product we discussed further developments and potential iterations. In future iterations we discussed a larger angle for the back of the chair, probably around 85 degrees. We also discussed alterations and additions to the writing table, making it more versatile and more aesthetic.

In final, the finished product was a success. A structural, comfortable chair for both Emily Car and her many dogs to enjoy. We are very proud of the final product.

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