Build Child-sized Boba Fett Armour Using the Pepakura Method

This tutorial will show how to make a Boba Fett costume for a child (9 years old in this case) using the Pepakura method.

"Pepakura" is a technique for making printable versions of 3D computer models.  The printout comes with numbered tabs and edges that are matched up and glued together.  When all tabs and edges have been joined, the result is a paper version of the computer model.

Pepakura models can be found on Star Wars fan sites.  For this project, I used the files found here:
http://www.therpf.com/f24/fierfeks-star-wars-pepakura-file-development-122071/.

The software for working with these models, Pepakura Designer, can be found here:
http://www.tamasoft.co.jp/pepakura-en/.

A complete list of tools and materials is attached.

Step 1: Measure the Child and Determine the Scale

Most Pepakura models found on the internet are adult-sized and will need to be scaled to fit a child.  Sizing the helmet is important.  If it's too small it won't fit, and if it's too large it won't fit well or look right.  The most important measurement for the helmet is front to back.  The head is longer in this direction than it is wide, so if the helmet fits front to back then it will fit side to side as well.  Measure from the tip of the nose to the back of the head.  You can have the subject hold rulers in place to help guide the measurement.  In this case, the measurement is right around 200mm.  The helmet model is 260mm in this direction (measurements can be seen in the lower right corner of Pepakura Designer).  200 / 260 = 0.769..., which is just over 3/4 scale, and is about the right scale for this subject given his height relative to my height.

Next, measure the arms from elbow to wrist for the gauntlets.  It's important to size the helmet and gauntlets appropriately.  The head must fit inside the helmet and the arms must go through the gauntlets.  If these parts are not sized correctly, it will be very hard to use them in the final costume.

Measure and scale for all pieces.  If you downloaded a complete set of armor models, the scale will probably be consistent, but this is not guaranteed to be so.  The surface-worn parts like the shoulder caps, knee caps, and chest armor are more forgiving with respect to size, but should still be scaled to fit the child.

Step 2: Scale and Print the Model

To apply the scale and print, open the model in Pepakura Designer.  Go to "2D Menu", "Change Scale", "Scale Factor..."
Change the value of the "Depth" field to your specific front-to-back measurement.  The model will be scaled down proportionally in all directions using the ratio given by (your value) / (the original value).

After scaling, some pieces will cross page boundaries, represented by dashed gray lines in the right side window of Pepakura Designer.  To fix this, go to "2D Menu", "Recalculate Parts Layout..."  Make sure that "Place Parts avoiding Page Borders" is checked and press OK.  The pieces will be laid out on separate pages and will print properly.  There may be some large white spaces between pieces.  Smaller pieces can be dragged manually into these spaces to require fewer sheets to print.

It is a good idea to print to a PDF rather than printing directly.  There are many free PDF virtual printer tools available on the internet.  For this project, I used PDFCreator.  This will guarantee that you can re-print exact matching pieces should any accidents occur during cutting or assembly.

When finally ready to print, use 110 lb card stock rather than regular paper.  This heavier paper will make a sturdier model and will be easier to work with during assembly and reinforcement.  The printed pieces will have numbered tabs and edges.  Every tab has a corresponding edge and both are labelled with the same number.  The model is assembled by matching every tab to its edge and gluing it in place. 

Step 3: Cut the Pieces

Use an X-Acto knife with a cutting mat to cut pieces from the card stock.  This is a time-consuming process.  Be sure to work with good posture in a well-lit area.  If desired, a ruler or straight-edge may be used to cut straight lines; however, working free-hand goes much faster.  Hold the paper down with one hand and draw the knife away from that hand.  Rotate the paper as necessary as you work.  It helps to have a 9" x 12" (or larger) cutting mat to make rotating the paper easier.

It's best to start with a recognizable part of the model.  For the helmet, start with the very top piece of the dome.  Cut pieces as you go instead of all at once.  By starting this way, the part can be test-fit as you progress and only minimal work will be wasted if the part turns out to be too small.

After each piece is cut, score and fold dotted lines.  Lines can be scored by lightly tracing with the X-Acto knife.  Dashed lines are "mountain folds", where the paper forms a "mountain" when laid on a flat surface with the numbers facing up.  Dash-dot patterned lines are "valley folds".

Some pieces will be so small that they are nearly impossible to cut and glue.  These pieces can be ignored.  They are usually small pin or button shapes and can be added as details to the final model using other improvised materials.

Step 4: Assemble the Model

With the pieces cut, scored, and folded, begin lining up the numbers and gluing the tabs.  Test the fit of each join before applying glue.  White glue works well on paper.  It adds no bulk to the joint, unlike a hot glue gun.  It takes 30 minutes to dry fully, but bonds paper to paper well enough to move on to the next tab after about five seconds.

Be sure to test-fit armor pieces on the subject as you go along.  If a piece seems to be coming out too small, consider re-doing the scaling and printing before continuing.  It's better to throw away a piece early in the assembly, than having to throw away a nearly or even completely done armor component.

Step 5: Reinforce the Paper Parts

The paper armor parts will be reinforced using fiberglass and resin.  These materials are available at home improvement stores.  You'll also need cheap paint brushes, rags, and acetone for cleanup.

FIBERGLASS RESIN FUMES ARE TOXIC and dust masks are not sufficient for blocking these fumes.  A reusable respirator can be had for $20 to $30 and is well worth the investment.  In addition, wear long sleeves, rubber gloves, and eye protecton when working with the fiberglass resin.

Mix the resin according to the package instructions.  Brush a layer on the outside of each piece and let cure.  When this outer layer is cured, add layers to the interior of the piece.  Embed patches of fiberglass cloth into these interior layers.  Brush on some resin, stick on the fiberglass cloth patch, then use the tip of the brush to pat in additional resin until the fiberglass cloth is saturated.  Overlap cloth pieces to ensure a solid final product.  The interior of the piece should be entirely covered in fiberglass cloth to maximize its strength.  Extend fiberglass cloth beyond the edge of each piece.  This will dry into sharp, pointy spikes, but these can be eliminated easily during the sanding stage.

Some pieces will be small enough that it is nearly impossible to fiberglass the interior.  The gauntlets, for instance, will be hard to coat with fiberglass cloth on the inside.  Skip the fiberglass cloth for these pieces and just add more of the resin.  Pour a batch of resin into the part and rotate it around for a few minutes until the resin hardens.  The longer you rotate the piece, the less resin will pool into one spot.  Repeat until there are no soft spots and the piece feels strong enough to wear.

Step 6: Sand and Fill

A fiberglassed armor piece will have jagged edges, drips, and flat spots that all need to be ground, sanded, and/or filled.  Large drips and jagged edges are easily ground down using a rotary tool with a sanding band.  After grinding drips and jagged edges, sand the piece all over with 60-grit sandpaper.  Since the piece began as a polygonal 3D computer model, it will have many flat spots in places that are supposed to be curved.  A good example of this is the dome of the helmet.  It is naturally supposed to be rounded, but  each card-stock strip that makes up the dome will make a flat spot in the completed shape.  To fill in these flat spots, use automotive body filler.  This is available at home improvement stores and isn't too hard to use, but will require a lot of sanding to achieve a smooth finish.  Body filler is a two-part sort of putty.  There is a base substance, with a separate hardener that usually comes in a tube.  Mix according to package directions.  An expired credit card or a used up gift card makes a good spreader.  Once the two parts are mixed, they will begin to harden fast so work quickly.  Mix no more than a golf ball sized amount.  Any more would require too long to spread.

When the body filler hardens, it will be very hard.  Early coats will have many lumps.  A rasp, 60- or 80-grit sandpaper, a rotary tool, or a palm sander all make good tools.  Use whatever you're comfortable with or have available.  Usually 3 or 4 applications of body filler will suffice to make a relatively smooth finish.  More coats will mean a smoother final product.  After about 3 coats, you can take a shortcut and begin to use wall spackle to fill in minor imperfections.  Use this only as a time-saving shortcut.  It is better to use body filler.

Step 7: Prepare the Helmet Visor

The visor area of the helmet is solid until now to keep the front of the helmet stable.  Before painting, cut this area out with a rotary tool and cutting wheel.  Stay a bit away from the edges of the cut out area.  Sanding down to the final cut line will give a neater edge than trying to cut directly along it.

The visor itself can be made from polycarbonate and window tint film.  Polycarbonate sheets are available at home improvement stores, and window tint film is available at automotive stores.  For this project, I used a pre-fabricated visor from t-visor.com.  This site specializes in Star Wars costume helmet visors.  Even though this helmet is 3/4 size, the standard "T" visor fit with only minor modifications.  To allow the visor to slide all the way down to the chin, I trimmed the corners of the vertical part of the visor.  

Step 8: Prime the Parts for Painting

When the armor pieces are sanded and filled, they are ready for paint.  The surfaces of these parts will have areas of resin-covered paper, areas of resin-soaked fiberglass, areas of automotive body filler, and so on.  It is important to use a primer coat to ensure that the paint covers and adheres to all these different areas.

Be sure to spray in a well-ventilated area.  Outdoors is best.  Use a drop-cloth, and if possible, suspend additional drop-cloths behind the area to help catch over-spray.  Several light coats are better than a couple heavy coats.

The primer coat will be the first time you see your parts in one uniform color.  You will likely notice many imperfections that you did not see before.  If these imperfections are bad enough, you may decide to do more sanding and filling.  If you do more filling, be sure to sand the primer off since the body filler will not stick well to the primer.  Parts like the helmet that will not be a solid color in the end can be a little more forgiving.  Multiple colors will hide imperfections better than one solid color. 

Step 9: Paint the Base Metallic Coat

Use a metallic chrome or silver paint for the next coat.  The final paint will be masked heavily to reveal this coat.  This will give the illusion of a metal helmet whose paint has been damaged in battle.

Metallic paint can have a greasy residue when dry.  Wash the parts with ordinary dish detergent to help remove this residue.  This will help the later coats adhere.

Step 10: Mask Off Some of the Metallic Silver

To achieve the battle-damaged look, the metallic silver must peek through.  The dent in the helmet, for example, should be masked through the entire painting process.  Also mask the face and ear pieces.  Use the blunt end of the X-Acto knife handle to push the tape into corners.  Mask off a big diagonal scrape over the right eye.  Tear off bits of tape to mask off any imperfections in the finish as well.  In the final product these will look like battle damage and won't be seen as imperfections.

For other parts, mask off the edges to give the impression of an old paint job that has worn off at the edges.  Tear off a strip of masking tape, stick it to a table edge and slice it into thin strips lengthwise with an X-Acto knife.  Use these strips along the edges.  Mask off random chips and scrapes around each part.

Step 11: Paint

The gauntlets get a base coat of red.  The shoulders and knees get a base coat of yellow.  After painting the base, remove all the masking tape to reveal the silver metallic.  Dust on some black paint by spraying at a further distance than if you were spraying to coat.  The light dusting of black paint will add to the battle-worn effect.

The paints used for this project:
* Rustoleum Satin Spruce Green
* Rustoleum Satin Colonial Red
* Rustoleum Satin Lemon Grass

The helmet and chest should get a base coat of green.  Dust the chest with black.

The helmet requires a bit more work.  Mask off the green, including the dome, back and cheeks.  Unmask the face (the part that surrounds the visor) to expose the silver.  Make sure there are still some battle-damage spots masked off with bits of tape.  If necessary, add a few more spots and slashes with bits and strips of tape.  Now, spray the face red.  Unmask the part of the face that angles toward the cheek plates and spray it black, again adding battle-damage if necessary.  Mask off everything but the earpieces and spray them yellow.  The range-finder base should be red.  Finally, remove all masking tape and dust with black.

Step 12: Stencil on Some Details

One shoulder and the right chest piece have a design.  A zip file containting the stencils used for these designs in this project is attached.  Print each stencil onto card stock and cut with an X-Acto knife.  Use red for the shoulder design, and metallic silver for the chest design.  Tape the stencil down onto the piece before spraying.  If the stencil is not secured to the piece the edges will not be sharp.

Step 13: Install the Visor

The visor used for this project the standard-sized model from t-visor.com.  It is a t-shaped plastic piece, tinted like a medium pair of sunglasses and curved to fit inside a helmet.  A similar piece could be made pretty easily by cutting the shape out of a polycarbonate sheet and heating with a heat gun to form the curve.  Use automotive window tint film to complete the piece.  For this project, however, I chose to save some work by using a pre-fabricated part.

The visor will be glued it with two-part epoxy.  Plus, stop blocks will be installed on the interior of the helmet around the temples to help hold the visor in place.  These measures should keep the visor secure even if the helmet is dropped.

First, gather three pieces of scrap wood, plus one wedge-shaped shim.  Working on the interior of the helment and with the visor in place, put one piece down the front of the visor.  Put another down the back and wedge the third in between.  Cut this piece to rough length if necessary.  Use the shim between this "bridge" piece and the piece in the back.  Driving the shim further in will push the visor more toward the front of the helment.  This set-up will keep the visor secure while the epoxy sets.  Mix a small amount of epoxy according to package directions.  Apply to the interior edges of the face plate where the helmet will meet the visor.  Put the wooden support set-up back in place and let the epoxy cure.

Cut two small wooden stop blocks to be glued behind the visor to hold it in place.  Glue these to the helmet in place behind the back edges of the visor's eye area.

Step 14: Make a Simple Rotatable Rangefinder

The Pepakura helmet model will contain a rangefinder stalk.  It will be very long and thin and not worth treating with the fiberglass and resin technique.  Instead, it will be used as a size and shape reference for a wooden version.  Trace the shape onto a thin piece of scrap wood.  Even a paint stirrer will do.  Choose a piece that fits snugly into the slot in the right earpiece.  A snug fit is import since the friction will hold it upright.  Trace onto the middle part of the wood, leaving extra material at both the top and bottom.  This extra will help in mounting the rangefinder, and in mounting the whole assembly to the helmet.

Cut a slot in the rangefinder to accept the stalk.  Put the stalk into the slot and mark the depth.  Add 1/4 inch to this and use that total measurement to mark the cut-line for the top of the rangefinder stalk.  Measure from the bottom of the horizontal part at the top of the rangefinder stalk.  Cut the top of the stalk and test fit it with the rangefinder.  The stalk should slide all the way into the rangefinder, leaving a bit of the wide part of the stalk exposed.

Mark the depth for the bottom part of the stalk using the helmet's earpiece slot as a guide.  Round off the bottom so that the rangfinder can rotate.  Leave a little extra material at the front to provide more friction.  Trim material from the back so that it doesn't extend above the earpiece when the rangefinder is rotated down.

Paint the rangefinder stalk metallic silver.  Mask off the part that will be inside the rangefinder itself so that glue will stick to it better.

Put the rangefinder in place in the earpiece.  Drill a tiny hole through the earpiece, the rangefinder stalk, all the way into the helmet.  This hold can be filled if desired, but should be small enough to be hardly noticed.  Secure the rangefinder from the inside using a small screw.

Step 15: Make a Simple Vest for Mounting the Armor

Using one of the child's t-shirts as a guide, cut a simple vest from some gray felt.  Cut some shapes from 6mm foam to roughly fit the chest armor pieces.  Use adhesive velcro on the foam and the armor to secure it in place.  Safety pins can be used to secure the sides of the vest.

Step 16: Pad the Helmet's Interior

Use the extra foam to add some padding to the interior of the helment.  Use a hot glue gun to glue strips down the middle.  Glue strips horizontally to protect the wearer's forehead and the back of the head.

Step 17: Wear and Enjoy

Take lots of pictures of your little bounty hunter.  My son will soon outgrow this costume, but the helmet will be a cool room decoration for years to come.