Anchor Build, Part One

I’ve been spending a lot of time watching other people build large props for costumes, so when it came to picking something for Dragon*Con this year, I decided to get in on the action, and build a weapon for Motochika Chosokabe from the Sengoku Basara videogame series.

The first step for this was gathering references. First and foremost, I had to scale things, because the character is tall and I… am not.


Scaling a Prop


Now, the way I did this wasn’t ideal. I didn’t have an image where the character was actually standing straight (he just… doesn’t) and the image has some serious perspective going on. But I picked what I thought was pretty close, and measured it (A). Then I measured the length of the weapon (B). It doesn’t matter how big the image is, since we’re just making a ratio of the two numbers. For the sake of the example, let’s say A was 6″ and B was 7.5″.  I divided B by A, and got a ratio ( 1.25) and then multiplied my height by that ratio (in this case 62″ x 1.25) .  Doing that tells me the prop should be 77.5″ to be the same scale compared to my height. I did the same thing with measurement C, which gave me an idea of how wide it should be. Of course, if you don’t want to do all that math, I suggest using this scaling tool to do all the hard work for you.

The next thing I needed was a blueprint for the head of the anchor. I could have tried drawing it myself, but that’s a lot of work. So I looked around until I could find a good side view, and used that, instead. I actually ended up using a picture of an action figure, because it was fairly accurate and had the view I needed.


This will be the blueprint!

I could have spent a lot of time tracing it out in Inkscape to get a really clean copy, but instead I just resized it in an image editor to the width I’d calculated, and then threw in MS Paint, because Paint lets you print a large image across multiple pages easily. You could also get it printed at a copycenter on a large-format printer, but this was cheap.



I decided the first version was too spindly looking, so I actually went back and reprinted it about 20% bigger. Better to be a little oversized with this sort of thing. Once I had this printed, I patterned the center portions out, as well as one of the ‘arms’ on separate paper so I didn’t have to deal with the taped-together printer paper.

Because this was meant to be a convention prop, I wanted it to be both lightweight and safe,  because cons get crowded, and I was going to have limited visibility when hauling this thing around. For that reason, the business end was made out of EVA foam.

I don’t actually have a lot of photos of the in-progress build for this, because I was on a deadline. But most of the parts were constructed out of two pieces 6mm EVA each, one front and one back. The edges were beveled at a 45 degree angle to make the sharp outer edges.

Each ‘arm’ had a v-shaped trench cut down the midline to form a ridge, and inside, sculpture armature wire was glued in with E6000 glue.


Gluing in the Wire

This was to help prevent too much wobble – I wanted it to be safe, but not droopy, because that would ruin the illusion. Then I glued the beveled edges together using contact cement. On the very ends, I cut extra material out of the inside, and used a heat gun to help form the domed parts. This was my first time working large-scale with EVA, and I could definitely improve on my cutting skills, because there were a few places where I couldn’t quite get the edges to match up. But over all, it’s not too bad.

I made the center of the anchor head much the same way, but this part also had a small diameter PVC pipe glued into it, since it needed to support the rest of the anchor, and attach to the pole later on.


PVC Pipe for Structural integrity

At this point, I had to figure out how to assemble the pieces, but still make it transportable. To do this, I added a chunk of foam into the end of each arm pieces, setting it back about 1/4″ from the edge. The foam had two rare earth magnets embedded into it. On the center section, I made corresponding diamonds of foam that fit into either end, also with magnets, being sure to flip the polarity, so that the two pieces would attract each other. I also added a foam ‘bracket’ to help support the arms.


Inside of one ‘Arm’


Pieces Fitted into Place


The end piece is just two pieces of foam with more trenches cut in them for shaping and glued together. Each side has velcro that sticks down onto the rest of the anchor. This covers the end of the PVC pipe, and is constructed in a way that’s easy to replace if it gets damaged.

The last part of this half of the build involved taking an external and an internal PVC coupler (sized for 2″ pipe) covering them in Smooth-On’s Freeform Air to make the decorative fixtures on this part of the anchor.


Holding Things Together

Once the Freeform Air dried, I glued the two pieces together, and then glued the center part of the anchor head into the internal coupler. The foam made a pretty snug fit, and glue means it’s not coming apart any time soon. I also left the small diameter PVC pipe a little long, so that when the whole thing is assembled, that end will be inside the pole a little bit to help make the joint more secure.

In the next post, I’ll talk about how I did the pole part of the anchor, and how I finished everything.