Parabolic Pencil Star

Introduction: Parabolic Pencil Star

Almost everyone has seen how straight lines can be turned into a near-perfect parabolic curve, and everyone has a bunch of pencils lying around at home or at the office that they don't use.  Put those pencils to use and build this neat pencil star.  The curves are created by following the same concept of drawing parabolic curves, except in 3 diemensions.  The entire thing is built with basic tools and can be created by anyone for free or for under $10.  It can look good in the office, or as decor around the house.

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Step 1: Supplies

80 pencils- $4 at the grocery store

marker or pen- free, for drawing lines to keep the pencils evenly spaced
Ruler- free, for measuring lines on pencils
hot glue gun- $5 or less at a craft store
cutting tool- I used a dremel with a cutoff blade, but a hacksaw from the dollar store would work just as well

An extra set of hands are very helpful for building the frame.

Step 2: Mark the Pencils

Measure the length of your pencil (mine were 7 1/2") and divide that by 7.  This will be the distance between your pencils (mine were 1 1/8" apart).  Mark 20 pencils at this interval.

Step 3: Build the Frame

Place 2 of your marked pencils and glue them together at a 60 degree angle.  I did this by creating an equilateral triangle and gluing it at one of the corners.  Just place a dab of hot glue on one of the pencil erasers and place the non-eraser end of another pencil on top. Hold the glue in place until hardened, and repeat until there are 10 pairs.

 *This is where it is very helpful for an extra set of hands*
Take 2 pencil pairs and glue the far ends at a 60 degree angle to the other pair.  The easiest way to do this is to use an extra pencil and create a tetrahedron with the extra pencil as an edge.  Do not glue this pencil to the frame.  Create 5 frames and you're ready to start making the curve.

Step 4: Create the Curve

This is pretty straightforward, but hard to explain in words, but pictures help a ton.

Line up a pencil eraser on the outside of the frame at the mark closest to the point.  Place the other end of the pencil at the mark closest to the opposite corner.  The pencil should just hang over slightly.  Put a dot of glue at each point where the pencils touch and hold the pencil in place until dry.  I recommend gluing the eraser directly to one of the pencils so you don't have to worry about trimming through the metal holding the eraser later on(step 5).  Then move to the second mark and repeat. Once you have glued all the pencils on the outside, flip the frame over and glue in the opposite direction on the inside.  When all the pencils are glued on, it should create a basket weave effect.  Repeat with the other 4 frames, and move onto the next step, trimming the pencils. 

Step 5: Trim the Pencils

Take your Dremel or hacksaw and cut off the extra pencil to create a nice, flush edge.  This gives the pencils a much more appealing look and makes the final assembly much easier.

Step 6: Final Assembly

Now that all 5 pieces are finished , just glue them together!  Line up 2 of the large triangles, glue one side, and press them together.  Continue until all 5 pieces are glued together.  The hot glue is flexible, so if your angles aren't perfect, they should bend and form together fairly easily.  Spend a few minutes picking off hot glue strands and you're done!  You can use your new sculpture as a lamp, as a piece of decor, or if you have a lot of pencils, experiment with other angles to create different shaped stars.  90 degree angles create a 4 pointed star.

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    4 Discussions


    3 years ago

    do you have a youtube of this so that I can follow on how t make this parabolic using pencil


    7 years ago on Introduction

    this is amazing!!

    I think that it could be done a bit differently with brochette sticks.
    although it would take less spacing.

    I'll try to do this, you bet!