Costuming 101: Assembling the Fantasy/Sci-Fi Armor

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Part II of 'Costuming 101: Building Fantasy Armor Using Discarded 55-Gallon Chemical Barrels.' We assemble the armor using pop-rivets...


Fantasy, Science Fiction and Medieval Armor Costume Construction

Part II, cont. from Costuming How-to 101: Fantasy Armor Created from a Plastic Chemical Barrel

This will be difficult to explain and provide graphic representations for. Assuming the reader has no prior knowledge or concept of how to do it, it would be equally difficult for me to explain and show by graphic images how to tie one's shoelaces or how to knot a dress tie while standing in front of a mirror.

The information on how to assemble the armor will be here. In the attempt to perform these steps the reader and hobbyist shall glean the spirit of the construct and likely come to understand the intention if not the exact method provided.

In the first installment of Costuming How-to 101: Fantasy Armor~, we learned some basics about procuring the required used 55-gallon chemical barrels and making a poster board template that is sized to the intended wearer.

Upon tracing the paper template onto a suitable cleaned and dry barrel, the two main carapaces are cut out using an electric jig saw. It is preferred to use an electric jig saw but these armor carapaces can be cut-out using a hand-held key-hole saw if necessary. In my first construct that is exactly the tools I used; a hand-held keyhole saw and several hacksaw blades. It took much longer and I receives numerous blisters and cuts for my efforts. Mainly, It just takes much longer and it is not as accurate as a power tool can produce.

With the carapaces cut out and using a serrated steak knife, all edges of the carapaces are draw-shave scraped to remove any ragged 'flash' plastic pebbles that the saw blade has created. Just a quick run on both side and both pieces is adequate. These will be finished much smoother later. For the most part, removing this flash with the serrated knife is just for keeping your work area clean of debris.

Using the propane torch for selectively heating and bending the carapaces in the required places and immersion in cool water to 'set' the bend permanently (as per the first installment of this series,) you should end up with two armor carapaces like the sketch below.

two halves of the HDPE armor, cut from a 55-gallon plastic chemical barrel

Two Carapace Halves

When all these steps are performed as per the Part I of this series, it brings to where we begin again; assemblage of the two carapaces.

This will form what I call 'chest cage' and shall refer to the joined carapaces as such in the future references.

In this Part II we will be using the Dremel or Black & Decker Rotary tool, and shall be introducing the use of a Pop Rivet Tool, along with stainless steel pop rivets and aluminum pop-rivet backing plates.

Required materials/tools:

  • Electric Drill, jig saw and Rotary Tool (and eye protection)
  • Several 1/8th drill bits. (keep several on-hand, they break sometimes)
  • 1/2-inch long, 1/8th diameter/gauge ALL STAINLESS STEEL pop-rivets (box of 500 recommended for price and value)
  • 1/8th dia. backing plates (Aluminum, available wherever pop-rivets are sold. Acquire several 25 count boxes)
  • Pop-rivet tool (also called 'pop-rivet gun') Avoid the 'cheap' models; expect to pay $30.00 - 50.00 for a good model. You won't regret buying quality.
  • Ball-peen hammer (claw hammer will suffice) and a thick heavy METAL surface to pound upon (an anvil is ideal, but a quarter-inch thick iron plate is fine)

Pop Rivets

Pop rivets come in a variety of sizes, lengths and finishes. Ranging from pop rivets made for use on computer cases and for specialty 'computer case modding' to general automotive restoration to a countersunk type for kitchen appliances, pop rivets are a builder's best friend when it comes to quick, sturdy and reliable attaching of two materials or dissimilar flat surfaces.

I use, recommend and highly advocate the use of aluminum 'back-up plates' on ALL riveted junctures for these constructs. A backing (or back-up) plate is nothing more than an aluminum washer that provides additional strength to the riveted joint. It prevents the flared end of the rivet from possibly pulling-through the softer HDPE plastic, even if subjected to great load or pulling force. These back-up plates are cheap. At around $3.00 for a small box of 25, you should have several boxes available along with the required 1/2-inch long 1/8th in. diameter pop rivets.

There are multiple sizes, materials and gauges of pop rivets but for our armor construction we shall limit ourselves to 1/8th diameter STAINLESS STEEL pop rivets that are 1/2 inch long.

My favorite type are the ALL STAINLESS STEEL pop rivets; not only is the break-away shaft stainless steel but so is the head. There are varieties that use a STAINLESS STEEL shaft but employ an ALUMINUM body. These are acceptable for use. But at all costs, avoid the use of the 'ALL ALUMINUM' pop rivet. These are intended for softer materials that do not experience great sheer-forces. They are inferior for our requirements and will break apart too easily.

This 1/2-inch length will allow us to adjoin two or more layers (thicknesses) of the basic 55-gallon barrel. While barrel thickness can vary greatly between makes, models and even within the same barrel, the half-inch length of our rivets shall prove to be more than adequate. There will be excessive 'tang' protruding through all riveted joints, but these can (with the use of those aluminum back-up plates) be pounded acceptably flat. Pounding-flat a excessively long pop rivet that does not have a 'backing plate' will damage the plastic and likely cause the rivet to punch-through the material. Use backing plate for all pop-rivets. It is cheap, effective insurance.

We are now ready to assemble the two halves and begin making the joined carapaces into a wearable unit that I call a 'chest-cage.'

NOTE: All graphics are NOT to scale and may not depict actual results. I have no actual images for many aspects of this armor construction. Your actual results will likely be superior to the graphics provided.

Two HDPE carapaces cut and bent to form the front and the back of the armor

Align the two halves of the carapaces to face each other, as shown here. The 'shoulder hooks' face each other, and one will over-clasp the other unit.

For clarity, these two halves are color-coded. "Blue" and "Yellow" are interchangeably considered to be 'Front' or 'Back' at this juncture. One carapace will always be smaller than the other, pretty much guaranteed. Proof? Try to make two carapaces exactly the same size! I have made several units and despite my best attempts no two carapaces are ever exactly the same width and girth. Made at the same time from the same template, one will always snugly fit inside of the other.

This is however, totally to our advantage. The LARGER one will over-lay the smaller one, as seen in this image below. Be sure however that BOTH shoulder straps of either color are either both on TOP or both UNDERNEATH. That is to say, both yellow are top or bottom, or both blue are on the bottom or on the top. So no 'co-mixing' of these union points as this create an undesirable 'twist' to the vertical alignment. This will make sense when aligning the carapaces together and it is difficult if not impossible to do it wrong, but it is worth mentioning.

Join the Two Halves so that one set of opposing but respective Shoulder Straps are Parallel and overlapping. Clamp firmly on either side of the dot-dashed lines labeled Rivet Corridor using two Vice Grips, or C-Clamps. For clarity in this image, over-lapping areas of carapaces depicted in GREEN.

Align One Set of Opposing Shoulder Straps and Clamp in Place

Join the two carapaces so that one set of mated should straps are parallel. Clamp in place

Looking down from the top of the two carapace halves, note that the shoulder strap of one aligns parallel to the shoulder strap of the counterpart. This will often cause an 'angular offset' to occur. The head-hole will appear to be too small for the wearer as well. Disregard this observation. This are acceptable and corrected in a later step.

Mainly, be thinking about the 'thickness' or 'spinal depth' of the chest-cage (your chest to spine thickness) while aligning the shoulder straps prior to riveting. If the chest cage looks too narrow-of-depth, it might actually be so and thus you have to 'open up' or lengthen the distance of the clamped shoulder straps.

If the chest cavity appears that it will be too large, slide the shoulder straps slightly closer together before riveting the first straps in place. Slightly larger than 'perfect body-tight fit' is optimal however. Remember' the wearer will likely be wearing clothes (shirt, sweater, chainmail, etc.) under this armor so slightly larger than optimal is better.

Clamp one or both sides of the shoulder straps union tightly using Vice Grips or C-clamps. Note the dot-dashed line marked "RIVET CORRIDOR." Drill and rivet only within the confines of this narrow corridor, at or near the apex of the union.

One hole at a time, drill a 1/8th hole and install a pop-rivet from the top side, using a backing-plate on the underside (toward the wearer.) Apply the rivet using the Pop Rivet Gun until the rivet 'pops' and releases the shaft.

Repeat this procedure until you have at least FOUR (or more, it's up to you) rivets applied. For your armor it may be desirable to counter-sink the drilled rivet holes before installing the rivet. This will make hiding the visible rivet head easier at the final stages. But if these rivets are desired to be visible such as in the suggestion of wrought iron-work, do not counter-sink the rivet holes. The exposed rivet heads (esp. when the whole armor is spray-painted!) provide a veritable 'iron-clad battleship' effect which is in itself, highly desirable for this genre of costume.

Perhaps careful consideration as to their spatial location (and patterning?) on the opposite shoulder to correlate with the first shoulder will suggest a more orderly Crusader-like appearance. It will appear to be professionally constructed (at least, by medieval iron-works standards.) The choices are endless for whatever effects you desire. Don't just through rivets in helter-skelter and patternless. Making each side match the other is the sign of a truly well thought-out construction process. I spent many hours upon completion, trying to 'hide' or 'relocate' rivets that were non-symmetric to the mirror side... Learn from my mistakes.

For the shoulder straps you MUST however remember to keep all the rivets within an imaginary Rivet Corridor (approximately as shown.) Note the CORRECT and the WRONG inset images for placement of these four (or more) rivets (depicted by RED DOTS.) It is important to keep your rivets within this narrower corridor. This allows for easier 'sizing' of the head-hole and shoulders straps later on. Saving time and resources are the major goal here. Re-doing previously-done work to correct for mistakes and make revisions for visual appeal only wastes time and materials.

On one very complicated armor build I spent nearly three years building and re-building it, allowing for the learning curve, mistakes made and of course, my do-overs. The second armor of that genre (scaled 1/3rd smaller for the intended wearer) only took one month to build on mainly an hour a few times a week, and intense weekend sessions! Such was the ease of not doing 'mistakes' and 'do-overs.'

Adjoin the Opposite Shoulder Strap of Your Armor

With one set of opposing shoulder straps riveted securely, pull the carapaces apart to align the second set of shoulder straps, and clamp securely. One hole at a time, drill and rivet this union together in FOUR places, using 1/8th inch aluminum backing-plates for added strength

With one set of opposing shoulder straps riveted securely, forcibly pull the two carapaces apart like a clamshell until the second set of shoulder straps align. Clamp securely using Vice Grips or other clamps, and one hole at a time drill and pop-rivet this union, again in FOUR places. Again, be mindful of the imaginary 'RIVET CORRIDOR' and stay within this area.

You should now have what I call a working 'chestcage.' Before it can be tried on, it must have several modifications made to it to allow for the wearer to get his or her head into the 'head hole,' arm-holes need to be sized and the four 'wings' around the left and right lumbar regions need to be trimmed to a useful and unobtrusive size.

Break-out the Rotary Cut-off Tool, Jig Saw and the Sharpie Markers!

For this next part we trim and size various aspects to make the chestcage wearable. Use a standard cut-off wheel (either metal or composite material) and trim-away the excess 'tails' of the shoulder straps. The top carapace (blue) shall be trimmed from the top or outside of the chestcage and the shoulder strap tails of the yellow carapace are trimmed-away from the inside. This does not have to be perfectly smooth. The Rotary tool is a blunt-force cutting tool; it does not leave smooth edges. These ragged edges will be re-visited later, making them smooth and comfortable. For now, removing the excess tails is for weight reduction, comfort, and to prevent clothing of the wearer from becoming snagged.

The excess tail material from both sets of shoulder straps are trimmed away using the Rotary Tool and cut-off wheel, and the slightly too small head-hole is sketched using a black marker and cut-out using the electric jig saw

Notice in the image above (and to the left) that the head hole is too small, and rather 'football shaped.' A person cannot possibly get their head into such a hole.

Using a sharp-tip magic marker pen, sketch a symmetrically pleasing oval around this irregularly-shaped head-hole as depicted by the red/black oval. Begin small. Cut out the sketched oval using the Rotary Tool and smooth it using the serrated steak knife to remove the pebbly flash material.

By holding the armor upside-down over the intended wearer's head, attempt to slide their head into the created hole. It will be necessary for the wearer to turn their head sideways to fit through this oval hole. This is how the armor fits. Otherwise, the hole we are making would extend too far down the chest and expose too much 'throat' area. The lowest part of the oval should ultimately be an inch or so below the 'V' at the front and base of the wearer's throat.

If the hole is still too small (and likely it will be on the first fitting,) continue tracing incrementally larger ovals, adjusting for a custom fit, and trimming the material off using the jig saw. Removing the 'flash' material with the serrated steak knife each time you make a jig-saw cut will make the job easier and less messy.

Repeat this sketch-cut-&-test fit procedure until the wearer can EASILY insert their head into and out of the hole. It should not be a tight fit or a struggle to get into or out of the head hole. Let's be real here; you do not want this to be too tight around your or the intended the wearer's throat. This is a costume armor; it should not be dangerous to wear. Treat and consider it as such, a safe to wear costume.

Using pre-marked lines, square-off the left and right lumbar tails, allowing the FRONT to overlap the BACK tail slightly, and make the arm-holes larger, oval-shaped and comfortable

Once the head-hole is large enough for the intended wearer to easily get their head into and out of the armor, the excess 'tails' that overlap the left and right lumbar regions need to be trimmed.

Both armholes also require some beautification and enlargement as well. This will require several try-ons and trimmings to get it just right for both sides. The arm-hole should allow the wearer to move their arms freely without great restriction. It must be a painless and comfortable fit.

Before trying it on however, the last section of overlap needs to be trimmed the sections on the wearer's left and right lower lumbar region.

You want the FRONT (shown is BLUE) to overlap the BACK (YELLOW) flaps. This overlap only needs to be an inch or so.

The rivet tails now need to be pounded flat. By positioning the armor so that the rivet's HEAD is against a solid iron surface (an anvil or steel plate, etc.) carefully pound the pointy-end of the rivet TAIL with a ball-peen (or claw) hammer until it is flattened. The aluminum back-up plate will keep the rivet's integrity while the rivet-tail will be flattened.

Once each rivet is suitably pounded flat (to some degree,) this task is complete. The pounded rivet-tails can later be smeared-over with a strong multi-purpose rubber bonding agent such as the adhesive "SHOO-GOO." The interior contact surface can thus be made to be even flatter. I find that this is often unnecessary, but a good thick smearing of SHOO-GOO over the riveted seams inside and covered with a patch of trimmed denim makes an excellent 'shoulder padding' from the potential irritant of the flat-pounded metallic rivet tail.

After using the serrated steak knife to 'draw-shave' the pebbly flash away, a propane torch can be used to GENTLY sweep the edges of the armor. The plastic at the edges will recede slightly from the flame, 'mound-up' ever so slightly and become shiny for several seconds as it cools.

DO NOT TOUCH THIS SURFACE until it is cool (usually under a minute.) The plastic will stick your fingers and burn horribly. Any tool that comes into contact with this when hot will 'pull' the hot molten plastic into hairs and strings.

Do try this torch-smoothing method on the cut, draw-shaved edges though. Within just a minute or two of performing this you shall become an expert in the technique. It is really easy and exceedingly fun to watch the plastic predictably and artistically behave this way, creating a very smooth and snag-free leading edge. This is one of the easiest things to do with HDPE-pastic armor.

Test the Fit of the Chest Armor: Make Adjustments as Necessary

The joined Front and Back carapaces now form the CHESTCAGE, which with a few trimming removed, can be test-fitted to the wearer

The armor should now be test-wearable. By gently expanding the base like an inverted clam-shell, the wearer can 'crawl up inside' of the chestcage, usually without the aid of an assistant or helper.

Here is where repeated measures and trims are required. It may also be required that the sides of armor (from the under-arms down) be slightly re-heated in strategic places using the propane torch and forcibly 'squeezed' into its counterpart half (maybe held in place using a stretchy belt or bungy cord) and quick-dunked in the cold bath water as per the first tutorial How to Build Fantasy/Sci-Fi Armor. This is 'ultra-fine tuning' to attain an exact shape.

What we have at this point is a basic 'chest cage armor.' There are many more features that can be added to your chest-cage to suggest surface details, seams, and intense battle damage.

These follow-up details can come in the next installment of

'How to Build Fantasy/Sci-Fi Armor PART III'

(all images and graphics by author)

NEW: Creating Leg Covers for the HDPE Armor by author.


Posted on Aug 17, 2010
Coda _
Posted on Aug 17, 2010
Emperor Frederick Von Seidl
Posted on Aug 17, 2010
Posted on Aug 13, 2010
Jerry Walch
Posted on Aug 13, 2010