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generally rectangular sections that are 25 mm x 100 mm x 1.6 m-

Overall To-do: -apply feedback to the confluence, detailed and clear manufacturing plain

Designed by: Ethan Sobkowich, Yanshen Zhou, Winnie Lin

Supervised by: Tommy Tran

Introduction

Purpose: Fixture for preparing adhesive test specimens of similar sizes (25 mm x 100 mm x 1.6 mm)

Needs statement: There exists a need to create a fixture that can hold specimens a stationary position for adhesive curing while being adjustable to different specimen sizes.

Constraints:

Functional Requirements

• All three adhesive joints curing at the same time

• Constrained movement in three axis

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• Maximize number of specimens that can cure at the same time

• Can be machined in-house

• Minimize time required to manufacture

• Maximize adjustability to different size

• Minimize costs for materials and manufacturing

-constraints: needs, functional, non-functional

*can organize into checklist

Testing between:

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Steel to steel

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Composite to composite

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Concept

The idea behind this design is to create a “tray” (Fig. 1) to constrain movement in the outer edges of the specimens. Multiple specimens can be cured at the same time in this tray. The spaces between each individual specimen will be separated with ladder-shaped rectangular 3D printed jigs (Fig. 2) as well as the spaces between each adhesive joint on a specimen (Fig. 3). A flat board/weights will be placed on top of all specimens to add pressure.

Testing between:

• Steel to steel

• Composite to composite

• Steel to composite

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Fig. 1: An image of the base tray for the testing jig

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Fig. 3: Example of how specimen will be placed in tray

Adhesive Anti-Sticking Solution

Adhesive to be Used: 3M DP 420 and Henkel EA E-120HP (both epoxy adhesives)

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https://www.seattletimes.com/life/food-drink/wax-paper-and-parchment-paper-are-not-interchangeable-plus-a-recipe-parchment-baked-salmon-with-orzo/ -create eng. design spec. chart

Engineering Design Specification Chart

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Overall: Saran wrap is the best material to use due to its ease-of-use and effectiveness. It is also one of the more affordable options and is easy to maintain.-other factors: interference with test specimen (wrap thickness)

Assembly Procedure 

Step 1: Printing

The pieces separating individual specimens and individual components within the specimen. 3D printing was chosen as the manufacturing method as they need to be thin (<1mm) to fit under the paces of the specimen.

1. Use PrusaSlicer to print an array of support pieces on the tray. Two of the longer spacing supports are required per specimen and 3 of the spacing supports are required between two specimens.

   1. You may need to change the dimensioning of the support beams to customize it to your specimen.

   2. Print according to the number of specimens that are cured.

2. Remove the printed pieces.

Step 2: Machining Cover

This component is placed on top of all the specimens after they are placed correctly. The purpose of this cover is to restrain joints with epoxy from lifting.

1. Measure and mark the area to be cut on the 3mm birch plywood. Ideally, each length and width should be 0.5cm less than the inner dimensions of the tray. For example, if the inner dimensions of the tray are 19cm by 24cm, then the dimensions of the tray are 18.5cm by 23.5cm.

2. Use a band saw in the design center machine shop to cut out measured dimensions.

Step 3: Laser Cut Tray

Laser cutting was chosen as the manufacturing method as it provides more cut precision when compared to manufacturing by hand. It is also faster.

1. Use AutoCAD to create layout of pieces that need to be laser cut. In total, this needs to include 4 copies of each component of the tray.

   1. The idea behind this is to stack four 1/8 inch thick pieces of fiberboard to create a 1/2 inch tall tray.

   2. Minimize the area occupied by the pieces. This is because the 3D Print Centre charges per square foot.

   3. All vector cut lines should be 0.00 units line thickness and all raster/engraving lines should be set to a minimum of 0.25 units.

2. Submit a laser cutting request: https://uwaterloo.ca/3d-print-centre/laser-cutting-request-form

   1. Turnaround time is 2-3 days.

Step 4: Anti-stick Solution

This is to prevent the epoxy from curing to the fixture. Ideally, we should aim for no epoxy bonding to the fixture.

Tray

1. Cover the inside of the tray with saran wrap

2. Press down on the inside edges and corners to try and flatten the wrap as much as possible

3. Trim excess saran wrap off the sides of the tray if needed

4. Tape down sides of saran wrap to the outside of the tray to prevent movement of the wrap

5. Place saran wrap on the flat surface where the curing fixture will sit. Tape down saran wrap to surface.

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1. Double wrap supports with saran wrap

2. Tape off loose ends 

Step 45: Placing Specimens in Place

This fixture is designed to restrain the curing specimens from movement in three axis. Proper placement of the support pieces and specimens are required to cure specimens properly.

1. Align first specimen in a corner with the longer side of the specimen touching the shorter side of the curing fixture.

2. Wedge a support fixture along the specimen to hold the individual pieces in place. Correct placement shown in fig. 4.

   

   Figure 4: The adhesive specimen is shown in blue. The support material is coloured in orange and labelled. They hold pieces on the same level in place.

3. Place three support pieces perpendicular to the first specimen at each joint to provide support for the next one. Continue placing specimens down until the tray is full or until you are satisfied with the number of specimens. If the tray is not full, wrap a flat piece of wood in saran wrap and place it flat against the last specimen. Put a weight behind the piece for support (i.e. a piece of steel, a block of MDF, a rock, etc.)

4. Place a flat board on top of the tray and specimens. The flat board should also be wrapped in saran wrap. Place a weight on top of the board.

Bill of Materials-pictures with assembly

-bill of materials w/ quantities + descriptions

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Material Specifications