| Surface Preparation |
| 1. | Roughen surfaces with 150 to 320 (US) grit abrasive. |
| 2. | Rinse off dust residue. |
| 3. | Clean with an alkaline cleaning solution or 70% isopropyl alcohol/water mixture to degrease. |
| 4. | Rinse in deionized water. |
| 5. | Dry at 100°C (212°F) for a minimum of one hour. |
| 6. | Apply adhesive or primer as soon as possible after cleaning. |
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| Adhesive Application |
| 1. | Apply in accordance with manufacturers instructions. Epoxies, urethanes and cyanoacrylates all perform well. |
| 2. | Apply uniform pressure until adhesive is set. Apply heat as required by the adhesive supplier. |
| 3. | Silane coupling agents can be used as a primer to improve adhesion if necessary. These are especially beneficial when bonding in high humidity environments. |
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| Joint Design Hints |
| 1. | Design joints for pure shear with uniform stress distribution across the joint. Cleavage and peel stresses due to bending should be avoided. |
| 2. | Lap Joints |
| | — Simple lap joints can result in cleavage and peel under load. |
| | — Joggle laps improve the stress distribution across the joint. |
| | — Double butt lap or double scarf lap joints further improve resistance to bending. |
| 3. | Angle Joints |
| | — Grooved joints (dado joints) offer good resistance to peel and cleavage. |
| | — L joints are fair. |
| | — T joints have good resistance to non-uniform joint stresses. |
| 4. | Butt Joints |
| | — Straight butt joints have poor resistance to cleavage and should be avoided. |
| | — Tongue and groove or scarfed joints are superior. |
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