The compact fluorescent lamp (CFL) has been around for a while and is slated to replace the incandescent bulb. But incandescent lamps are still the most frequent representation of light bulbs seen in art. As someone who believes that inefficient technologies should make way for better ones, I decided to help the process along by using only compact fluorescent lamps in my artwork whenever a light bulb is needed. This three-part tutorial documents how I finally managed to model one of these twisty energy saving light bulbs.
A note on terminology: For the longest time I thought fluorescent was spelt fluourescent. That spelling might creep in somewhere in the tutorial. In fact, I originally named the page fluoresent, as in sending some fluor. Also, I do not really know what the proper name for these light bulbs are. I have seen them variously called energy saving light bulbs, twisty light bulbs, spiral light bulbs or compact fluorescent light bulbs. So I am going to use these terms interchangeably. If the world cannot make up its mind about what they are called, far be it for me to try to change that.
The tutorial is split up into several parts due to the number of images. As someone who usually publishes technical papers on image processing, I can't resist paraphrasing the famous quotation that is written in nearly every journal article, “This tutorial is organized as follows:”
Before starting, first set the Sub-D Type to Catmull-Clark subdivision surfaces. This will simplify things with 6 point polygons in the intermediate steps as well as allow for the use of edge weighting / sharpness to set how sharp edges are supposed to be.
The plastic housing is the plastic part of the light bulb that houses the internal electronics. The bulb's fluorescent tube comes out from one hole on top of the housing and goes into to the the other.
Make the first hole from which the light tube protrudes by adding a 6 sided disc with the following settings (the top view is shown):
Select all the points and use Extender Plus to extend the points and rescale these newly created polygons to create a ring around the original disc. Next, select the three points closest to the Z-axis and Extend them. Set their X coordinate to X = 0 (Info → Edit All → X). These steps will produce the following:
Now mirror what you have created along the Z-axis:
For those familiar with face modeling, you may notice that the process being used here is similar: start at the eyes and then work your way out. This makes it easier to set up the edge loops necessary for the holes in the CFL housing.
Create a 12 sided disc, then Kill the newly created polygon (leaving only points):
Now connect the points from the geometry you created earlier with the points from the 12 sided disc:
Extend the outer ring of points and scale them to be slightly larger:
Extend the outer ring of points again, but this time bring them down 30 mm, creating some volume to the object. Then, make a new edge loop (Knife tool works fine) between the top and the bottom. The following figures show the side views for this step:
Shape the base by adding additional edge loops and symmetrically scaling them:
Now, look at the top of the housing. Select the hexagons at the top and then bevel them according to the next three figures, producing the protrusion from which the fluorescent tube emerges:
Select the edges indicated in the figure and set their sharpness to 100 percent (do this for both of the protrusions created above):
Finally, create two new edge loops near the top of the housing to form a thin strip. This corresponds to the seam between the top and bottom pieces of the plastic housing on a real energy saving light bulb. Select a few polygons from the strip and Bandsaw as shown below. Select the polygon loop created by the Bandsaw and smoothshift them inwards by 0.5mm. These steps are shown below:
Turn on Subdivision surfaces to at what it looks like so far:
This completes the modeling of the plastic housing.
→ Continue to Part 2: Modeling the threaded screw cap and electrical connector
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