# Exercise 205/6

Introduction:

There are two primary ways to use the power of 3D computer modeling software to produce architectural models. In this exercise, you will explore “modeling through layers of details.” For this exercise, you will be modeling both a piece of a concrete walking bridge and a glass "spider" clamp.

Part 1:

• Begin by drawing the shape documented below (units are in inches). The point indicated by the arrow should be the origin (0,0). This is the cross-section of the bridge you will be making. For this step, you will need to use Snap (Rhinoceros 5.3 [grids]), Osnap (Rhinoceros 5.4 [osnap]), & the polyline tool (Rhinoceros 5.5 [polylines]). You may wish to do this step in the “Top” viewport, then switch to the “Perspective” viewport for the next step.[Premium Content - Login] [Membership Options]
• Next, use the Rotate3D command (Rhinoceros 5.6 [rotate3d]) to rotate the object into the vertical position.
• Now, use the Offset command (Rhinoceros 5.7 [offset]) to create another object 4 feet from the first.
• Select both objects and type “explode” to create individual line segments from the polylines.
• Select two opposing curves and use the Surface>Loft command (type “loft” in the command line) to create a surface between the curves. Repeat this process for each pair of curves.
• Next, draw two diagonal lines (dashed below) across corners of each end and two horizontal lines extending from the walking surface to the outside of the section (shown dashed below also).
• Select the curves surrounding each potential end surface and use the Surface>Patch command (patch) (Rhinoceros 5.8 [patch]) to create 5 surfaces for each end of your object.
• Now use the Surface>Chamfer Surfaces (type ChamferSrf into the command line) to create beveled corners between each surface. You will need to adjust the distance to be 1/2” (0.5”) then select the first surface followed by the second surface.
• When you have finished chamfering both sides, use the Edit>Trim command (type “trim” into command line) to clean up any unnecessary surfaces.
• Using the skills you learned in Exercise 204, assign a concrete material to the object and place an infinite plane below your object.
• Note: This should be below your object and you may need to move the plane vertically to satisfy this condition.
• Set up a view of the final object that you like. Click the render button on the toolbar (or Render>Render) to create a rendered view of your final shape.
• Post the rendered image to the course website. You don’t need to comment on this exercise.

Part 2:

• Begin by drawing the shape to the right. You will likely need to use the Polyline tool (Rhino 5.5 [polyline]) as well as the Arc tool. Pay careful attention to measurements.
• Next, use the Rotate3D command (Rhino 5.6 [rotate3d]) to rotate the shape up into the vertical direction.
• Use the join command (Edit>Join) to join all of your lines together
• Now, use the circle tool to draw a circle at the endpoint of the object.
• Use the Sweep 1 Rail command (Rhino 5.10 [sweep]) to create a tubular surface that defines the steel rod used in the spider clamp.
• Next, use the circle tool to define the 1.5” buttons at the base of the steel rod created in step 5. Refer to drawing on the back of this page.
• Use the Surface>Extrude Curve>Straight command (extrudesrf) to create the surface of the button. Make sure to change Solid to “Yes.” The button should be 0.5” thick. Repeat for the opposite side of the steel rod.
• Use the Copy/Move commands to make a copy of your piece. Use the rotate command to rotate it 90 degrees from the first one (to make an “X”). You now have the base of your steel spider.
• Next, using the methods discussed above, create the tension rod that extends from the steel spider to hold the 3/8” diameter tension cable. Refer to the dimensions on the back of this sheet if necessary. (This should test your understanding, which is why I’m not writing a step by step guide.)
• Now, at point (0,0) create a 4’ x 6’ x 1/2” thick piece of glass (rectangular surface)
• Move your finished spider from above to rest on top of the piece of glass as indicated in the plan on the back of this sheet. Add the 3/8” steel cable to the height of the glass.
• Once you have the final piece assembled, use the Rotate3D command to change the whole unit so that it rests in the vertical plane.
• Now, assign each object a material. You should assign the material by layer rather than by object (this will be demonstrated in the lecture). Save your .3dm file and your rendered image.