20. An acoustic baffle

This exercise will show you how you can easily unfold an object (e.g,. to make a template) with Amapi 3D. You will use the “working plane” facility to punch a true circular hole on a sloping plane.

Draw the box

Þ Step 1: The cube

q Tool: Cube q Do it: 1. Face view (2). 2. Select the Cube tool. 3. Draw a cube with the following dimensions: X=50, Y=80 and Z=50. q See the detailed explanations in the chapter: User Manual/Tools/Construction/3D Primitives/Cube

Þ Step 2: The cutting line

q Tool: 2D Drawing tool, Polylines q Open the model file: Enceinte01 q Do it: 1. Side view (key 4). 2. Select the Polyline tool. 3. Use polar coordinates (PC: Click on the right mouse button, Mac: Hold the Option key pressed and click the mouse button). 4. Draw a line, with an angle of 60° from the vertical axis. This line will cut the upper face of the cube. q See the detailed explanations in the chapter: User Manual/Tools/Construction/Drawing/Polyline

Cutting the cube with the line

q Tool: Punch q Open the model file: Enceinte02 q Do it: 1. Side view (key 4). 2. The cube is the current object. 3. Select the Punch tool. 4. Click on the cutting line. 5. The cube is split. 6. Select and delete the volume with the triangular face. 7. Now, we get the baffle body. q See the detailed explanations in the chapter: User Manual/Tools/Model/Cut/Punch

Punch the loudspeaker’s hole

Þ Step 1: Changing the working plane

q Tool: Control Panel, Working Plane q Open the model file: Enceinte03 q Do it: Now, we will change the working plane to drill perpendicular to the face (to avoid drilling an oval hole). 1. Select the Working Plane tool in the Control Panel. 2. Click on the sloping plane: Amapi 3D rotates the baffle so that this plane matches the nearest orthogonal plane. q See the detailed explanations in the chapter: User Manual/Tools/Control Panel/Working Plane

Þ Step 2: Draw the shape to be punched out

q Tool: Drawing tool, Circle q Open the model file: Enceinte04 q Do it: 1. Face view (key 2). 2. Select the Circle tool. 3. Draw a circle with 16 points, centered on the front face. q See the detailed explanations in the chapter: User Manual/Tools/Construction/Drawing/Circle

Þ Step 3: Punching

q Tool: Punch q Open the model file: Enceinte05 q Do it: 1. Side view (key 4). 2. The baffle is the current object. 3. Select the four points of the front face. 4. Face view (key 2). 5. Select the Punch tool. 6. Click on the Circle: the face is punched. 7. Select and delete the circular face. We have made the hole for the loudspeaker. q See the detailed explanations in the chapter: User Manual/Tools/Model/Cut/Punch

The loudspeaker

Þ Step 1: Drawing from the loudspeaker’s hole

q Tool: Curve Extract (Automatic boundaries extract method) q Open the model file: Enceinte06 q Do it: 1. Face view (key 2). 2. Select the Curve Extract tool. 3. Validate. The tool uses the Automatic boundaries extract method. A Circle is automatically generated from the punched hole 4. Put the tool aside. q See the detailed explanations in the chapter: User Manual/Tools/Construction/Extract Curve /Automatic extraction of the contour lines

Þ Step 2: Loudspeaker extrusion

q Tool: Extrusion q Open the model file: Enceinte07 q Do it: 1. Side view (key 4). 2. Select the Extrusion tool. 3. Extrude the loudspeaker profile (cone + cylinder) 4. Close only the back face. q See the detailed explanations in the chapter: User Manual/Tools/Construction/Extrusion

Þ Step 3: Coming back to the original working plane

q Tool: Control Panel, Working Plane q Open the model file: Enceinte08 q Do it: Now, we will change the Working Plane to come back to the original working plan. Select the Working Plane tool in the Control Panel. The baffle is tilted and lies on its base q See the detailed explanations in the chapter: User Manual/Tools/Control Panel/Working Plane

Baffle filleting

q Tool: Fillet q Open the model file: Enceinte09 q Do it: We can refine our baffle by rounding the angles: 1. The baffle is the current object. 2. Select the Fillet tool. 3. Set a small fillet radius. 4. Validate. The result is an acoustic baffle. If you apply a nice rendering texture, it might look nice in your living room... q See the detailed explanations in the chapter: User Manual/Tools/Modeling/Chamfer

Unfolding the baffle box

q Tool: Unfold q Open the model file: Enceinte09 q Do it: We could need to have a planar version of our baffle in order to build it. NOTE: Do not unfold a filleted object. We will unfold the filleted version of the baffle box. 1. The baffle is the current object. 2. Select the Unfold tool. 3. Choose a facet to start the unfolding: for example, the smallest vertical face. 4. Unfold. The result is a template. Now, you can measure the faces, or print to scale, or... q See the detailed explanations in the chapter: User Manual/Tools/Assembly/Unfold