Sewn Construction for Armor with Worbla’s Black Art

One of the most interesting builds we have seen in a while, we sponsored All Tomorrow’s Patterns (GillianConahan on IG)  in this sewn armor build using Worbla’s Black Art, and shared the process with us! Take a look at this method, and see if it might help you in your next build!

Foam may be the most common support material to use with Worbla materials, but it’s far from the only option. I’m always looking for options that will retain Worbla’s most useful properties but add structure and strength as needed – especially those that won’t off-gas when heated, which can cause bubbles in your worbla in addition to being hazardous for your health.

For this armor I decided to try using the cotton canvas I’d already purchased for the base layer vest and harnesses. Although cotton can scorch at very high temperatures, it’s perfectly fine in the normal working range for Worbla’s Black Art, and it’s nicely crisp and easy to work with and doesn’t fray excessively. You can control fraying still further by zigzag stitching over the edges and/or running a line of water-based glue along each cut edge, working it into the fabric and allowing it to dry before you continue.

Since I was already adding fabric to the equation, I decided I’d go ahead and try sewing my armor together. It was even more effective than I would have hoped! Worbla’s Black Art is sticky enough to bond to the fabric while working, but still moves through the machine easily even when warm – so you can sew it while it’s soft and flexible. While stickier Worbla materials like Mesh Art are also theoretically sewable, they have to be worked while cool (or at least partially cooled) so they’ll be harder to manipulate into shaped seams.

Unlike foam and other materials that are typically held together with glues or the Worbla’s own adhesive, the fabric substrate retains its proportions and structure even when the Worbla is in its softened state, so it resists distortion and can be restored after crumpling or crushing. Also, by placing a solid object behind the fabric you can create a hard base that won’t squish or dent when you press on it with a sculpting tool, so it’s easier to smooth and sculpt as well.


  • Canvas or heavyweight muslin (100% cotton is best)
  • 1/4″ Cotton twill tape for reinforcing edges
  • Water-based fabric glue to prevent fraying
  • Thread
  • Sewing Machine
  • Denim needles
  • Worbla’s Black Art
  • Fasteners and attachments of your choice
  • Scraps of Worbla’s Mesh Art for reinforcement
  • Flexible primer (such as Flexbond) and paints



The pauldrons are simple pieces shaped with darts, so they’re a great place to start. Create a rough version of the shape with tinfoil covered in masking tape, (01) then cut darts or seams into any curved areas until the piece can lie flat. The darts will be smoother and easier to sew if you curve them a little, so the transition at the point is as gentle as possible. Mock up your preliminary pattern in heavyweight non-woven craft interfacing, using a zigzag stitch to join the edges with no seam allowance required. (02) Refine the shape as needed, making sure that you know how you plan to join the layers. The lowest layer in my example is more fitted, with three short darts to round it around the shoulder. The middle layer has one long dart for a more gently curved shape, and the top tier has a seam down the middle. Each pair of tiers joins at two pivot points, front and back. (I was still thinking some things through, so I patterned the first two tiers and started the final version before going back and figuring out the top tier, but in other situations it might be more sensible to do them all at once.)

Once you’re happy with the pattern, cut your pattern pieces out of the canvas, omitting all seam allowances. Cut the same pieces out of Black Art, leaving about a half inch to fold in around the edges but cutting exactly at the edge of the fabric for any internal seams and darts. (03) Heat your Worbla’s Black Art and place the fabric, making sure it’s smooth and flat and evenly adhered. The Black Art isn’t very sticky, so you need to get it quite hot and press down firmly on a hard surface to prevent the layers from separating as you work with them.

Set your machine up with all-purpose thread and a zigzag stitch, about 1.5-2mm length and as wide as the stitch will go (6mm on my machine). I got good results with a universal needle, approximately size 14. A denim needle might help if you need more piercing power. Start sewing at the point end of the dart, making sure that the zigzag catches both sides and easing the sides of the dart together as you sew toward the open end. (04) You may find it easier to pull the dart closed if you soften the worbla before sewing, but you may also get some crumpling or buckling in the areas around the seam that you’ll need to correct afterward. The fabric helps the piece to retain its shape, so you don’t need to worry about stretching or distortion too much. (05)

After sewing, reheat the piece and press it on a smooth surface (I use a glass trivet) to bond the Black Art across the dart and also bury the stitches slightly so they’re easier to smooth over later. (06) You can leave the seam as is at this point and smooth the area when you prime the piece (the stitches absorb the first coat but disappear nicely after 2-3 coats of Flexbond) or use an additional strip of Black Art to cover and blend the seam. Trim the ‘hem’ to an even width and fold the edges in. Heat thoroughly and use a sculpting tool to blend the edges into the fabric lining so they stick. (07) If not adding a sculpted border, I also like to run a flat tool along the edge of the piece so it’s crisp and square.


To attach the pauldrons, I made a canvas cuff to go around my upper arm with a short length of elastic on the underside and an extension at the top to go through a small rectangular ring. (08) Once you have the cuff fitted to the correct size and length, join it to the inner layer of the pauldron with stitches or rivets. You may need to reheat the pauldron piece slightly to get it to move through the machine nicely, but then you can attach the strap with a simple back and forth straight stitch. For the multi-tiered pauldron, I used snap tabs looped through the rings to join the tiers, which allows for some movement and allows the pieces to be separated if necessary. Another snap tab joins the pauldron to the base vest. The back banners are attached to a spring clip that hooks onto a small D-ring on a strap riveted to the inside of the pauldron. (09)


The breastplate uses a similar but slightly more involved construction method. I developed the pattern from my personal block using flat drafting techniques, but you could also use a commercial pattern or the tape wrap method to get the necessary shapes. (10) Use heavyweight muslin or similar for the first mockup, then draw in any extra seams and construction details and transfer them back to the base pattern.

Since I planned to combine the Black Art breastplate with a leather and canvas base vest, I constructed the vest first to ensure the pieces would fit together correctly (11) and then mocked up the breastplate in more craft interfacing and made any necessary corrections. (12) When fitting a rigid breastplate, remember that the front chest measurement between the shoulders is important for mobility. If you make this area too wide, it will prevent you from moving your arms forward. If you look at historical breastplates, they usually cut in here for exactly that reason.

The breastplate design uses a three-piece cup set into a frame piece that goes almost all the way around. In this case, I decided it would be easiest to use a lapped construction to set the cup into the frame, so I added a 3/8″ seam allowance on the cup pieces only for both fabric and Black Art. As with the pauldrons, first stabilize the fabric pieces to prevent fraying. All edges without seam allowances get zigzagged and brushed with glue, and the edges with allowances were straight stitched along the seam line. You may also wish to trim these edges with pinking shears to soften the edge and make it less visible. Clip into the seam allowance up to just before the stitching line to allow it to flex. (Space the clips about 3/8″-1/2″ apart, using the pinked edge as a guide to keep them even.) (13)

Even sturdy fabrics like this canvas can be prone to stretching on the bias, especially along curves and narrow extensions like the lower part of the frame. These areas can be stabilized by stitching cotton twill tape along the edge where the cup will be inserted – zigzagging at the cut edge and straight stitching along the interior edge. (14) If your tape is 100% cotton, you can shape it around the curve by pressing and steaming it with an iron. If I was doing it again, I would have also stabilized all the outer edges of the piece in the same way.

Adhere the cups to their Black Art layer just as before. (15) Trim exactly to the cut edge along the internal seams, but you can leave a little extra along the frame edge to help with blending. Cut the Black Art for the frame piece as well, but don’t apply it to the canvas yet. The full breastplate gets a little large and unwieldy to maneuver through a domestic sewing machine, so the cups will be sewn into the canvas layer alone and the Black Art applied afterward.

Assemble the cups using the same method that was used for the darts, using a wide zigzag stitch with a short stitch length and easing the edges together from one end to the other. Heat and press on a hard surface to smooth and blend. Then, heat the outer edges and bend them outward a little so they’ll be flat and ready to go into the frame. (This is why the canvas edges needed to be clipped, since they don’t stretch the way the Black Art does. If you missed that step, just clip into both layers now.) (16) Transfer the placement line for the lapped seam to the outside of the cup by stitching along the seam line again, this time through all layers.

Get the edges of one cup piece nice and hot so they’ll stick to the canvas frame and hold it in place for stitching. Place the frame on top, making sure to match any construction marks and pressing down firmly. Place it in the machine with the cup to the left of the foot, so it doesn’t get in the way of the needle bar as you stitch, and zigzag flat all the way around the cup. (17) Repeat for the second cup, which may be somewhat harder to maneuver depending on the size of your breastplate and machine. You may need to soften the Black Art so it can be manipulated out of the way, then reheat to restore the shape afterward.

Once the cups have been inserted, you can apply the Black Art to the frame. (18) Fold the hem extensions in around the edges just like we did on the pauldrons. If you forgot to leave a hem allowance on any of the pieces, you can apply a separate strip of Black Art to the inside and blend it over the edge to join it.

The large breastplate piece will probably take some work to get smooth, since the cups will want to pull the piece into a body shape while gravity wants to pull everything flat. One solution might be to do this on a dress form, if you have one that will tolerate the heat well, or just heat and shape small sections at a time, shaping the piece over a hard ball or your knee to help get smooth curves. The canvas will tend to pull the piece smooth and take the shape that you’ve patterned in as long as everything is well supported and not sagging under gravity. (19)

Most of the breastplate does pretty well with the basic layers of canvas and Black Art, but I found that the ‘bridge’ area between the cups was particularly prone to buckling and wrinkling due to the contrast between the more rigid seam allowance and the flat fabric between. I added a small piece of Worbla’s Mesh Art to the inside to help fill and support this gap, as it’s stickier and sturdier than Black Art and thus perfect for reinforcement. I also blended strips of Black Art across the seams in the cups, to help smooth and add structure before I sculpted details on top. (20)

Choose your breastplate fasteners according to the type of support needed as well as the underlying structure. I used trouser hooks at the shoulders to take the main weight, and magnetic snaps at the underarms as an easy way to keep the plate from shifting around. The trouser hooks are the prong-back kind, with little teeth that pass through the fabric and worbla layers and clamp onto a support plate. (21) I usually stick a dime under the edge of the hook to prevent me from squishing it flat while I bend the teeth down with pliers. (22) The magnetic snaps (usually sold as purse clasps) are similar, but because the tabs are wider and rounded you’ll need to cut slits in the material to fit them through, so be careful to get the placement right on the first try. (23) After applying the fastener, you can conceal the back plate by blending another scrap of Black Art across it. (24)

For the lower corner of the breastplate I simply cut a hole that allows the side strap to snap through onto the base layer. (25) This works because these heavy-duty snaps have a certain amount of inherent thickness, but you need to be careful that your canvas and Black Art layers don’t exceed that thickness or they’ll interfere with the functioning of the snap.


This is a slightly eccentric detail of this armor, but I include it because it uses a third type of assembly that doesn’t appear elsewhere on the set. For this piece, both sides are visible, so the final piece has a ‘sandwich’ construction with Black Art on both sides.

The pattern for this piece was developed using the same method as the pauldrons, building up the shape with aluminum foil and masking tape and then cutting the pieces apart. I also made note of where it crossed the underlying harness straps, so that I would have a guide for adding attachments later. The components have different curves and join at an odd angle, (26) so they seemed like they would be difficult to ease together in a butted seam. The solution was to apply Black Art to one side of each piece, sew them together with a conventional seam, and then apply the other side of the ‘sandwich’ to cover the seam allowance.

When cutting out the fin pieces, include about a 3/8″ seam allowance on the canvas only. The Black Art does not extend into the seam, but it has a 1/2″ foldover allowance around the outer edges. Cut one pair of fins in canvas and two pairs in Black Art, and sew twill tape just inside the stitching line as described for the breastplate. Clip the seam allowances as necessary around any sharp curves. Apply Black Art to the outward-facing side of each piece, and zigzag stitch over the edge right along where the seam will be to keep it in place during assembly. (27)

When sewing Black Art face to Black Art face, make sure you place something between the layers so that they don’t bond together under the pressure of the foot. I used a strip of cotton bias tape, as it’s easy to manipulate along the seam line and can be peeled up once the Black Art is cool. (28)

It’s normal for one or both pieces to ripple as you’re easing two different curves together, but this can make the piece difficult to maneuver if it stiffens too much while you’re still sewing. You may need to stitch the seam in sections, reheating in between to keep the whole piece soft and workable. Make sure your tape barrier remains in position between any areas where the Black Art layers are in contact, but doesn’t cross the actual stitching line or you won’t be able to remove it. Overlap several stitches each time you stop and restart the seam to prevent it from unraveling. Afterward, make sure you neatly clip all your thread ends to keep them from getting fried by the heat. (29)

Fold the outer edges over, and blend them in as smoothly as possible as another layer of Black Art will be added on top. (30) The pieces get much more rigid once the other layer of is applied, so it’s a good idea to add any sewn-on hardware at this stage as well. I sewed in three snap tabs, one at the peak of the curve and one on either side where the armor piece lines up with the harness underneath. (31) The other half of the snap can be applied to the base harness once the shape and placement of the fin are finalized.

If you notice that the seam is taking a lot of stress in certain areas, or if you want a little extra reinforcement and rigidity, you can add a strip of Mesh Art across the seam line on the less visible side. You’ll be able to smooth it out some by blending the backing layer of Black Art across it, but the seam allowances still tend to create a bit of a lump that needs some work to look neat. Apply the second layer of Black Art and smooth all seams with a sculpting tool. You can trim off the foldover allowance for the second layer, or leave the excess material in order to sculpt a raised edge detail. (32)


Once the base forms are complete, you can go back and plan out your detailing. You can draw the design on your original pattern pieces, (33) or design directly on your assembled armor with a pencil (34) or by laying down a layer of masking tape to draw on. (The nice thing about this is that when you’re happy with the design, you can peel up the tape, cut out individual design elements, and stick them directly to another piece of Black Art as a guide for cutting.)

Preshape the sculpted elements as much as possible to avoid distorting the base pieces when you reheat to attach them. (Some sculpting in place will still be necessary as you will need to shape the detail pieces over a curved surface, but the more you can minimize it the better.) Spirals and swirls are easiest to create by starting with a plain strip, folding and rolling it into a snake, and then coiling it into the final shape. (35) For simpler leaf, scale, or petal shapes, it may be easiest to cut out the finished shape with scissors and then refine with sculpting tools. (36) For repeated elements of consistent size, like when you’re building a symmetrical design, I like to cut 1/4″ or 1/2″ strips of Black Art and snip off matching pieces in order to make sure that each component starts with the same amount of raw material.

I also like to finish my armor pieces with a sculpted border, which is usually a simple strip of Black Art cut to roughly twice the desired width and then folded in half lengthwise to give it more substance. I coil this strip into a spiral and heat until the whole thing is very flexible, then lightly warm the edge of the armor piece so it’s tacky and lay the whole border in place. From there it’s an incremental process of reheating and refining a few inches at a time to create your desired border shape, which can be rounded, square, beveled, or have more elaborate sculpted details as you prefer. (37)


I used the same fabric-backed method to construct the vambraces (38) and helmet (39). The small wings on the back of the costume were constructed similarly to the sword, (link to sword tutorial), with a cardboard base and a mix of Worbla products to assemble the structure and add sculpted details. They’re built around a wire core repurposed from a heavy-duty drapery hanger, which slides into a loop sewn to the back of the armor to attach. (40)


Because all the pieces go together with snap tabs and Chicago screws, the multi-tiered pauldrons and vambraces can be completely disassembled for paint. (41) The combination of fabric and one or two layers of Black Art remains fairly springy, so you will want a primer with some flexibility to avoid issues with cracking. I used Flexbond for most of these pieces, which can be smoothed with a soft wet brush between coats. For anything with exposed cardboard (like the wings,) use caution selecting primers and do a test to make sure you won’t cause warping or rippling, but good quality backing board or book board may be fine even with water-based primers like Flexbond. Most of the armor is painted with a light-bodied matte black acrylic, with gold metallic acrylic that I dulled down with some pewter to get a more subdued shade for the accents. The metallic is not entirely opaque, and I applied light coats over the black with a dry brush to give it a slightly weathered finish. (42)

The Finished Build!

Gillian also created the sword you see pictured using Worbla’s Black Art and cardstock – and shared the process to make your own! You can find that tutorial here: Cardboard Sword Build