Intro: Bloom Parametric Pendant Lamp
Bloom is a parametric pendant lamp created with Grasshopper 3D. This instructable will cover how to cut and assemble one, as well as the concept behind the GH definition and how to manipulate the design.
If you don't have access to Grasshopper, you can use the provided templates in AI and DWG format to cut your own. If you don't have access to a laser cutter, but have lots of free time, it's still possible to cut by hand with an exacto.
Step 1: What You Will Need
1. Material - Anything thin, flexible and cuttable. I used a wood veneer. (You can try a rigid material if you're feeling lucky and use the GH definition with the kerf bending option)
2. IKEA Hemma pendant lamp cord http://www.ikea.com/us/en/catalog/products/1017581...
3. 1/8" metal brads for attaching the pieces (plastic rivets may be a more elegant and permanent solution)
4. 6 bolts #6-32 x .5" (a more elegant fastener might look more... elegant)
5. 12 machine nuts #6-32
6. 3D printed replacement part for the IKEA cord, file attached (this is not required, but if you don't use it, you'll have to figure out another way to attach the lamp).
Step 2: Cutting Your Parts
You can use the templates provided here, or skip to the steps describing the GH definition to design your own.
I cut my parts out of a thin birch veneer with paper backing. If you are using a material with grain, it's important to lay-out the parts so that they will bend with the grain.
I taped my veneer down to a piece of carboard to keep it flat while cutting. The veneer will warp once it's cut, so watch it carefully. I had to pause the laser cutter frequently to remove the loose parts.
Once all the pieces are cut, organize them into groups. If you are using a template, you should have 6 of each part.
Step 3: Assembly
Begin by inserting 6 of the machine nuts into 3D printed base. Next, bolt together each of the #1 pieces as shown. The side with the single hole goes above the top of the side with 2 holes. Loosely screw a nut onto each bolt, then screw each bolt into the 3D printed base as shown.
If you aren't using the 3D printed base, you can attach the #1 pieces with metal brads.
Step 4: More Assembly
Next attach the #2 pieces to the #1 pieces with metal brads as shown. The side with the single hole attaches to the outside, and the top of the side with 2 holes attaches to the inside.
Repeat this step for every piece.
Step 5: Hang Your Lamp!
Next, screw the lamp cord onto your beautiful finished lamp and put in your bulb!
I used an LED bulb. Depending on your material, you may want to use a CFL or anything that doesn't get too hot.
Enjoy your lamp! The next steps will cover the Grasshopper definition and how to design your own.
Step 6: Grasshopper Definition
This section of the instructable will cover the attached Grasshopper definiton. You will need to download FabTools from http://www.blickfeld7.com/architecture/rhino/grass... to use the unroll feature. You will also need paneling tools for Grasshopper http://www.food4rhino.com/project/pt-gh if you don't already have it.
The original concept started as an experiment using paneling tools to panel developable surfaces that could be unrolled and cut from sheet material. I found the trick is to panel only the linear profile curves of your surface. That way the morphed curves remain linear and when lofted they are still developable. The last part of the definition unrolls each surface and uses paneling tools to morph a 2D kerf bending pattern onto the flattened surface. This is still experimental and I am working on a method to get repeatable, working results. Stay tuned for an update on parametric kerf bending.
Step 7: Defining the Form
The first part of the definition defines the shape of the lamp with two graphs. The first graph is an exponential curve, which defines the length of the lamp. The second graph is a sine wave, which defines the profile of the shape. The yellow panels below the graphs display the overall length of the lamp, and the start and end radius. Make sure the start radius is over 1.3" to fit over the 3D printed base.
"Panel Offset" defines the 'thickness' of the panels. "V Number" defines the number of duplicate pieces (set this to 6 unless you want to design a different 3D printed lamp base). "U Number" defines the number of pieces vertically.
Step 8: Shape of the 'Petals'
The shape that is paneled is created by a series of rotated and scaled lines. These lines are morphed onto the lamp's UV surface, then lofted. The shape is defined by two graphs. The first graph is a sine wave, which defines the scale of the 'petal'. The second graph, also a sine wave, defines the curve of the 'petal'. These should always be a single sine, with the bottom ends of the waveform at each end of the graph, but feel free to experiment.
Step 9: Adding Tabs
This part of the definition adds tabs to the flattened 'petals'. The titles of the number sliders are pretty self explanatory.
Step 10: Parametric Kerf Bending
This part of the definition is still experimental, and optional. It uses paneling tools to morph a 2D kerf bending pattern onto the surface, in order to bend a rigid material along a curve. I have only tried it with 1/16" cardboard, but it should be possible with other materials. You will have to experiment with the spacing of the kerf pattern with different thicknesses of material.
"V Number" should remain at 1, but feel free to experiment. "U Number" defines the spacing of the kerf pattern. The two "Factor" sliders define the length of the kerf lines.
"Frame Offset" defines the spacing of the flattened 'petals' when you are ready to bake them.
If you make a lamp or a variation of the grasshopper file, please post it here and share it!
Enjoy your lamps!