Introduction: Realistic Spider (Life-Size Prop)

About: Illegitimi non carborundum.

Thanks to all of the voters who helped this instructable place in the 2010 Halloween Contest!

Need a realistic, life-size spider?

Try out this design - using little more than scraps of paracord and wire, you can create a lifelike spider in an hour or less.

Whether for an inexpensive prop, a simple prank, or a frightening seasonal decoration, this instructable will help you make a tough, virtually-indestructible spider that will be much more realistic than the crudely molded toy spiders that one can find commercially available.

Recently, I found myself in desperate need of a spider. My search was triggered by the startlingly visceral close-up magic effect created by Jim Pace ("The Web") and further developed by Andrew Melia ("Box of Fear"), which I in turn have adapted to my own impromptu street style of performance.

After frustratedly searching the internet for a life-sized spider model that would suit my application, I stumbled across a unique website, (featuring the amazing work of artist Gary Owen, whose creations are featured in many commercials, films, and TV shows). After seeing photos of his lifelike replicas, I was inspired to come up with my own simple method for creating a spider.

My goal was to create a replica spider with readily available materials and that could not be pulled apart, no matter how realistically fragile in appearance. This spider costs next to nothing to make, and can be built under almost any conditions.

Step 1: Tools and Materials.

You will need:

  • 550 cord  ("paracord", 2 pieces, approximately 8" in length)
  • wire (see notes below)
  • super glue
  • paint marker, modeling paints, or pigment markers
  • pin
  • lighter or pencil torch
  • scissors or a knife
  • wire cutters (or fingernail clippers if using small-gauge wire)
  • an assortment of small pliers / forceps (at least two)
  • leather gloves (recommended)

Other considerations:

For 550 cord (type III parachute cord, or paracord), I recommend tan, OD green, or black. Each of these colors will result in subtly differing shades of dark brown or black when melted.  If you are able to keep it from burning during the melting process, white 550 cord will take minimal amounts of carbon from the flame, resulting in a slightly translucent and lighter brown color.

Select wire gauge based on the desired diameter of your spider legs and proportional to the overall spider size that you wish to construct.  By my best estimate, the wire that I used for this project is 26 gauge, or 0.018" in diameter.  I would have preferred to use wire with a much springier quality, such as piano wire, in order to resist deformation when the spider is crushed, but I don't have anything else available to me at this time.

More on material selection - if you want to, you could experiment with other types of synthetic rope or cord for the spider body.  Each different polymer type used in the rope fibers will have different melting characteristics, so keep that in mind.  Again, I am constrained by materials available to me.

Optional materials:

In conjunction with 26 gauge wire, you can choose to add segmented legs using approximately 8" of CAT5 cable, or insulated wire of a similar size.  If you are using larger gauges of wire for this project, then you will need to select an insulated wire of corresponding internal diameter.

Step 2: Form Spider Abdomen.


First, a few warnings to protect yourself and your work environment.  This step requires extreme caution and adult supervision, if applicable, as it involves molten plastic and open flame.  Wear gloves and use forceps or pliers to keep the hot plastic away from your skin. 

Always allow the cord to cool after heating - the plastic can appear to be solidified, but will remain in molten liquid form for up to one minute after removal from heat.

Complete this step in a ventilated area - fumes from burning plastics can cause lung irritation and dizziness if inhaled.

Protect your working surface - drips of molten 550 cord will permanently damage
carpet, unfinished and finished wood, and fabrics.

With those caveats out of the way... the construction process begins.  This is the trickiest part of the spider construction, as the size and appearance of the abdomen will dictate how the rest of the spider looks.

For extremely small spiders, I recommend "gutting" the 550 cord - remove the inner strands and work with only the outer sheathing material.  This will help reduce the size of your finished product.

Begin by slowly heating one of the ends of a length of 550 cord.  Rotate the cord, avoiding drips, until you have accumulated a small blob of melted plastic about the size of a pencil eraser.  Allow this to cool, and then set it on your working surface. I used forceps to secure the cord and suspended it over the edge of my work table (as pictured in the 3rd photo below).

Take a second short length of 550 cord and begin to melt it.  Allow it to ignite, and then, with a stroking motion, "paint" additional layers of smooth plastic over the original blob.  Each time the burning "paintbrush" is applied, the flame will extinguish, and you will need to melt and ignite it again.

Once the desired size and smoothness is achieved, the abdomen is completed.  In the accompanying images, I stopped once my spider abdomen reached the size of a coffee bean.

Step 3: Attach Spider Legs.

Cut four lengths of wire for your spider legs - I recommend that you use a minimum of 6" lengths to facilitate handling throughout the attachment.  Snip the ends of the wires at 45 degree angle to allow easier penetration through the 550 cord.

Naturally, the portion of the abdomen that you built up in the last step should face upward. Visually divide the height (as viewed from the side) of the 550 cord into thirds, and poke sideways through the bottom third of the cord with a pin, entering and exiting as close to the abdomen as possible.  Remove the pin and gently slide one of your wire legs through the slight hole that you have created. Stop once the wire is centered on the cord.

Carefully bend the wire and tie it into an overhand knot around the bottom of the future spider body.  Pull the knot tight using two pliers or forceps.

Reinsert the pin into the side of the spider body, entering and exiting as close to the first wire as possible.  Thread in the second wire, and repeat this process until you have all four wires centered and tied.

Step 4: Form Spider Jaws and Head Section.

Trim off the excess 550 cord approximately ¼" from the forward set of legs.

Jaws. Take a fifth section of wire and bend it into a narrow "v".  Place a small drop of super glue onto the point of the "v", and then insert the wire into the body of the spider as far as possible, trying to touch the abdomen.  Maintain rearward pressure on the wire for a few seconds until the super glue sets.

Bend the "v" open and widen it, then carefully melt the open end of the 550 cord until you have formed a small head, with the wires that will serve as the spider's chelicerae or "jaws" protruding outward.  DO NOT touch any wire components during this step, as metals conduct heat and could burn you.

Cephalothorax.  Spiders only have two body sections, the abdomen and the cephalothorax.  This part of the spider (also called the prosoma) is a combination of the head and thorax seen in insects. 

Reignite your "paintbrush" segment of 550 cord, and daub a small amount of melted cord over the back of the spider, and joining to the head.  This covers the remaining exposed 550 cord and forms the spider's cephalothorax.

Step 5: Shape and Trim Legs and Jaws.

While shaping the spider's legs, I suggest referencing a photograph of a spider so that you can better replicate a natural form and posture.

Bend all of the legs sharply upward, and then spread the legs apart symmetrically.  With a pair of pliers, place the first bend in each leg.  Place the second bend in each of the legs, then trim to an appropriate length.

Spider legs actually have seven different sections (coxa, trochanter, femur, patella, tibia, metatarsus and tarsus, with the femur, tibia and metatarsus being the longest), so if you want higher levels of realism, adjust accordingly.

Pull the two chelicera (jaw) wires across each other, and trim.

Step 6: Add Leg Segments and Paint.

If you want a spider with thicker legs and visible segmentation, then include this optional step - otherwise, skip ahead to the bottom of this step and continue with painting.

Segmentation.  Neatly strip the insulation off of an internal strand of CAT5 cable or insulated wire as mentioned in the materials notes.  Discard the wire and save the insulation.

Straighten the legs of your spider, ensuring that you can still see where the original bends were located.  Cut small sections of insulation to approximately match the length of each leg segment.  As you slide the insulation onto the straightened legs, secure in place with a tiny dab of super glue.

At each bend, or "joint" in the leg, leave a small gap between sections of insulation - I used a gap of approximately 0.5mm on mine.

Painting.  Using your modeling paint of choice, or a paint marker, paint the legs. If you skipped the preceding optional step, you can leave small gaps in the paint application, or use differing colors along the length of the leg to visually imply the presence of joints.

You can paint the body of the spider with pigmented technical pens if you need a spider with patterned coloration.  I recommend Pigma® Micron® pens, available from any art or hobby supplier.

Bend the legs back into position if you straightened them for the segmentation enhancement.

Step 7: Completed Spider!

Your new spider can now be employed as deviously or innocently as you wish.  At a glance, or even upon casual examination, this prop can be easily mistaken for a real spider - unlike the appallingly cheesy molded spiders that litter fake spiderwebs during the Halloween season.

Due to the materials used in construction, your spider can be suspended or positioned in any posture, and will survive a great deal of abuse. Even if startled individuals attempt to "kill it", a little gentle reshaping of the legs is all that is needed to return the spider to duty.

Pictured are a few spiders made with differing methods.  The photos below include the spider made in this 'ible, and two additional ones without leg segments. 

This design can be modified as necessary, to include detailed hand-painting, addition of adhesive and hair, or even careful heating or filing of the legs to create a more natural taper.  Feedback, suggestions, or pictures of your own spiders are welcome.


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