I'm going to try something new with this particular project. Instead of dividing up the work across multiple blog posts, I'm going to put everything in this single post, but update it as I progress. So if you want to follow along, bookmark this page and check back regularly.
This year at San Diego Comic Con, WB/DC had a TON of great costumes on display in their pavilion, from both movies and television. It was actually quite stunning to be able to see so many iconic and awesome costumes up close. Downside is they were all behind plexiglass, which made photography problematic.
A couple of things that really caught my eye were the Wonder Woman shield and sword. With such amazing reference material available, and my little brain already at work figuring out how I can replicate these, I finally got to work.
Here's a picture of the shield. If I had to lay odds, I would say that this particular one was not screen used, but is instead part of a "Touring Suit." For all intents and purposes, it's identical to the ones used in the movie, this one just wasn't used in the movie. this is all conjecture, mind you, but it fits with the facts I have available to me.
My initial impression of the shield is that it's not terribly complicated. It has a great paint job on it, and the only thing that really struck me as challenging is the lettering that encircles the thing. The shield has a number of layers on it, which immediately struck me as something I could vac form over a buck, and then just cut it up to replicate the different steps.
Which means that the first order of business is to fabricate a buck that will be used in vac forming. My approach to building this buck is to create a skeleton out of MDF, fill the voids with foam, then shape it to where it needs to be. Let's begin!
We start with a blank canvas. Well, more precisely, a couple pieces of 1/4" MDF. Available at Home Depot.
I had originally considered the idea of getting the skeleton pieces laser cut, as it would be faster and more precise, but ultimately the logistics and cost proved to outweigh the convenience of simply making it out of MDF. Though I will lose a degree of precision, as regular readers of this blog will know I am constantly struggling to LOSE my crippling inclination towards perfection, and I think chosing MDF is a good step in the right direction. Remember, better to have a finished piece that isn't perfect, than a perfect piece that isn't finished!
I start by creating a simple jig out of styrene which will allow me to draw a circle. Since I know what the diameter of my shield needs to be, I take half that distance, and poke two holes in styrene at that distance. One hole will be used to nail the styrene to the MDF, and the other will be used for the pen. The hole created by the nail serves the dual function of also providing me with a center point of the circle. That will come in handy later.
And here are the results of my high tech circle drawing solution. I'm using a fine point sharpie to mark the MDF. It's more resilient than pencil, but it's also more broad and noticeable than a regular pen.
I used my circular saw to cut the MDF piece in half, just to make it more manageable.
And then I cut it down even further, thus making room for my coping saw to do all of the heavy lifting. I wasn't going for precision here at all, just trying to trim off the fat to make the next step easier.
If I had a band saw or a jig saw, I would have used it at this step to do the fine trimming on the circle. But I don't. I actually prefer to do this stuff by hand as it allows me greater control, and if I screw up, I can stop quickly and back up. Notice that at this point I was not going for precision. Just trying to get it within an 1/8" or less. Or so.
In case you didn't know what a coping saw is, that's one sitting on top of the circle I just cut out.
For the very fine tuning of all the shapes I'm cutting out of MDF, my plan is to use my table top disk sander. I can get VERY precise with it. First step is to calibrate the table to make sure it's at a right angle with the disk. I did this using a right angle bracket that I typically use for machining. This one is a little rusty. Remind me to clean it up sometime.
And here are the final results, after carefully running the edge of the circle through the sander. I am extremely happy with how this turned out. Looks really great. Now granted, I could have had a circle laser cut to precision... but where's the fun in that?
See how close it is to the pen? Nice!
Next up is to draw reference lines on the disk. This will help me place the ribs/slats down. I start by using a right angle ruler and just drawing straight through that centerpoint that I created earlier with the nail. Handy, right?
Then it's just a matter of using the ruler, a 45 degree square, and a compass to map out the rest of the lines. I'm dividing up the buck similarly to how it's done on the final product. Might be overkill, but the more ribs I have on the skeleton, the more uniform my final shape will be.
Now I'm going to start creating the ribs. A couple things are very important here. One is that the bottom edge of each slat be perfectly straight. This will serve to eliminate any warp in the disk, and I can tell you right now there is a little bit. When the MDF stock sits on the shelf at Home Depot for a few months, it tends to warp and bend a little under its own weight. No big deal. I also need to make sure it's the right width. The outer tips of each rib have to precisely touch the outer rim of the circle. Or as close as I can get it.
The next step is absolutely critical, as it will define the entire shape of the shield. I used a picture of the real shield for reference, and did my best to estimate the shape of the curve. It's a pretty shallow curve, by my estimations. Even if this is off, I'm not too worried about it. If better reference becomes available, I can always just start again. Wah wah.
What I'm going to do is create a styrene template that represents one half of the curve of the shield. I'm doing only one half so that I can duplicate it across a slat to get the entire shape. This will allow me to ensure that it is symmetrical. Which is also pretty important in a project like this.
I cut out a rough shape in styrene, and then fine tuned it with a sanding block. Once I was happy with the final shape, I marked off a point on the styrene that was the length of the radius of the disk. Here's what the final template looks like.
I start by laying the styrene onto the MDF strip. I once again put my angle to use to make sure that the lower lip of the template is butted squarely up against the lower lip of the MDF. I need this placement to be consistent across all of the slats, or else ... bad things. Like crossing the streams and all that. Dogs and cats living together. You know the routine.
With the center point marked, and my knowledge of how wide the slats need to be, it's then a simple matter of just flipping the styrene template over and marking the other half of the MDF slat.
It's pretty much magic.
Here is the slat all drawn out on the MDF. I'm now going to follow the exact same procedure I used on cutting the circle. Start with a coping saw, then take it to the bench grinder for fine tuning.
Here's the first slat all trimmed and ready to go.
Test fitting! AND it's perfect! The edges line up really nicely, and the center point matches. I'm really happy with how things are shaping up at this point.
I cut the second one, and cut opposite teeth in both slats so that they would fit together. The idea is that these really serve as anchors for the rest of the pieces.
I'm using regular old wood glue to attach the slats to the disk. It's like building a TARDIS all over again!
I glued the two slats down and clamped the edges into place. This effectively got rid of any and all warping of the disk along the two main axis. Good stuff! Looking great so far!
Fast forward, all the slats are now in place. Aside from those first two ones, the rest were all half slats.
After the glue had a chance to dry, this is how it turned out. I'm EXTREMELY happy with the results. Looking GOOD!
Now it's time to fill in all the gaps in between the ribs. My original plan was to use pink insulation foam, mainly because I had some on hand. The plan is to cut it into wedges, then glue them in place. Because the shield is taller than 1", I'll need to do two layers.
Using the same jig I created for drawing the circle on the MDF, I draw a circle on the pink foam. It's going to be a little too big, but who cares. I'll just trim it.
Just like with the MDF, I then use rulers and stuff to map out all the pie wedges.
For cutting the foam, I'm using one of those long bladed box knives. I keep a sharpener handy to make sure the cuts are as clean as can be. Spoiler alert: it was not sharp enough and some of the cuts are kinda chunky. It really doesn't matter though, as this foam will be buried deep within the shield.
Here's the foam all cut into wedges. Yay!
The final item I completed in this, my first day of building, was to glue the foam wedges into place. Honestly, I don't even know if the wood glue will hold, but time will tell. The good news is that I don't need much tenacity, as it only needs to hold the foam in place until I vac form the thing.
That brings to a close this first entry on the build. Everything you see here was completed in one day. In hindsight, it really doesn't seem like that much was accomplished, but much of the work was very repetitive and precise, which is really what took so much time. Stay tuned!
July 29, 2015 Update
Much has been accomplished in an afternoon of work, though some mistakes were make. As with almost every project, new things are tried, and new lessons are learned. New skills established and all that. This project is no exception.
The first thing I did was trim away a bit of the pink foam. I used my coping saw and that big old blade I showed a picture of earlier.
And let me stop right here to say THIS is the point where things go sideways. My original plan was to cut more pink foam, glue it into place, and then shave it down to shape. Just like I did the first layer. But for some reason, I wanted to try something new. A friend of mine from Germany, Svetlana Quindt AKA Kaumi Cosplay, has done some truly amazing things with expanding spray foam. I watched one of her entertaining and enlightening tutorial videos a while back, and thought I would give it a try.
Please check out Svetlana's website at https://www.kamuicosplay.com/ and do yourself a favor and purchase one of her e-books. Amazingly well written and insightful. You'll be making armor like a pro in no time!
Honestly I think my big mistake here was not letting the stuff cure overnight. Or maybe I got the wrong brand. Or maybe something else. Still, live and learn.
Here's the stuff I picked up from Home Depot. Seems simple enough.
Here is the stuff right after it has been applied to the shield. Yes, it expands a lot. More than I anticipated, but that doesn't really matter.
Then I left the workshop to go see "Ant-Man," which I really enjoyed. When I came back to the workshop, the foam looked like this.
It was, for the most part, rigid. But it still had some give to it. That should have been my first indicator.
I once again employed my coping saw and a long blade to cut the expanding foam to shape. It actually looked pretty good.
I think used my orbital sander and a sanding block to get things closer to the shape I wanted them to be.
The bummer about foam is that fiberglass resin doesn't like it. Actually, I should be more clear. Some foams don't like some resins. I'll leave it at that, and leave it as an exercise for the reader to determine which foams don't like which resins. In general, the polyester resins that you will find at your local auto parts store or Home Depot are going to be caustic and corrosive to these types of foams. It'll be a total disaster.
With that in mind, a common technique employed by foam builders, and folks who work with pink foam, is to coat the foam with a layer of white glue, or in this case "Mod Podge" to create a barrier between the resin and the foam. The glue does not react with the resin in a bad way, and therefore blocks the resin from wrecking the foam. That all sounds great.
A couple bummers to note at this point. There were GIANT bubbles/holes in the expanding foam I used. I don't know if I did it wrong, or if that's just how this particular brand of foam works. Also notice that by this time, the foam was contracting a lot. A. LOT. And that didn't make me happy.
However, I proceeded with my plan to apply a coat of Mod Podge to the foam, which overall went just fine.
At this point I was kind of thrown off my game, and it went downhill fast from here. I then brushed on a couple of coats of West Systems EPOXY resin. In hindsight, I don't think the epoxy resin would have damaged the foam. I could have saved the Mod Podge step.
I was going to throw some matting onto the shield to help build it up, but because the Mod Podge had not yet completely dried, I just kind of danced around the still-wet parts and did what I could.
And that's where it stands after session number two in the workshop. I have the pink foam shaped pretty well, and swiss cheese expanding foam collapsing by the minute.
July 31, 2015 Update
Today was a productive day, though tiring. In between giving a lot of my attention to some new breakthroughs on my Superman Returns Cape project (YES, that project is STILL going!!!) and cleaning up the shop, the work on the shield really fell into the tired old loop of putty/sand/primer/repeat, which regular readers of this blog will know what a huge fan of that process I am.
I ended up brushing on a couple of coats of Smooth-On 300, which is great because it cures quickly. I figured using the West Systems stuff was just going to delay the project, as it takes about 24 hours to fully cure. The 300 is ready to be sanded in 15 mins, and it can be used to build up recesses quickly.
I also used some Evercoat kitty hair to fill some of the bigger voids, many of which were created when I carved out chunks of the orange expanding foam which really never got fully rigid. That's another bummer that resulted from using that spray foam instead of just cutting up more pieces of pink foam.
A couple coats of Rustoleum automotive primer later, along with a few applications of Bondo spot putty, and things are starting to look good. In general, I do not like Rustoleum primers, but for this project I found it suitable because first of all, they have it at home depot and it's fairly cheap, second it's a pretty heavy build primer, and third MDF tends to soak it up so it's great for filling it in. Same thing with bondo spot putty. Not the best putty and I would not recommend it for a finished prop, but for something like this which is going to be used as a buck, I like it because it's cheap, readily available, and also sands very easily. Using something like full blown Bondo or an Evercoat product would be overkill because it's expensive, and it's also much harder to sand.
Lastly, I put together a quick video showing what the shield looks like after this third day of work. Check it out if you are interested!
August 6, 2015 Update
I can now say with complete certainty that it was a flat out, full on mistake to use that spray on foam stuff. While it may have valuable applications on a variety of projects, this is not one of them.
The bottom line is that the foam never truly gets rigid, nor does it keep its shape. It seems to expand and contract based on temperature, which is a real bummer.
My attempts to get the surface of the shield smooth and uniform were constantly thwarted by the changing landscape of the shield, caused by the foam. After two days of wrestling with it and trying to compensate for the expansions or shrinkages, I have given up. That is to say, I'm just going to consider this "good enough" and fix any imperfections in the styrene pull that comes out of the vac form machine.
THAT said, I think it's really looking good so far, and I think whatever is produced by the vac machine will be a great starting point for the rest of the project.
August 24, 2015 Update
I have started building a vac form table to help out with this project. I made a separate blog entry for it, so as to not entirely clutter up this post. Check it out right here!!!