Creating Spartan Matthews

[Matthews 027]

Hey Y’all!

I’m Matthews, and this is my first ever Halo cosplay! For this build thread, I want to share everything I’ve learned so far—why I made the choices I did, how I figured things out step by step, and how I planned this whole thing. But first, let’s start with a bit of background and why I’m even doing this cosplay in the first place.

I’ve been gaming ever since I could hold a controller and form a halfway coherent thought. The first game I ever played was Halo 3 with my dad. From the very beginning, I was hooked—I had never seen anything like it. That game sparked my love for shooters and became this special way to spend time with my dad.

Then 2009 rolled around, and the Halo: Reach trailer dropped. My dad, his friends, and I were beyond excited. In 2010, he took me to the midnight release at GameStop. I was only nine years old, so staying up until midnight alone was the coolest thing ever—but going to the launch of a brand-new Halo game? Unreal. We were there for hours, hanging out with other fans, joining the activities the employees had set up, and then my dad walked out with that massive Legendary Edition box.

We got home, unboxed it, and then I saw the statue. Up until that point I thought Master Chief was the coolest Spartan ever—but then I laid eyes on Noble Team. Their armor designs were so unique, so different, and I knew instantly: that was the team.

Playing Reach with my dad, watching the campaign unfold—it shook me. I had never cried over a game before, never been hit that hard by a story. We played it for years on the 360, joined Halo parties where everyone would bring TVs and Xboxes, and it was just pure magic. Eventually, though, life got busier. I grew up, my dad’s friends drifted away, other games came along. But deep down, I always wanted that same kind of friend group my dad had built through Halo.

Fast-forward to 2022: I started streaming on Twitch and met my friend Pax. He invited me to my first convention in Kansas City, Missouri. We decided to cosplay together, and though I had never cosplayed before, I’d done theater and props in high school and thought, this can’t be too different, right?

I made a Reaper outfit from Sea of Thieves, flew to the con, and quickly realized… I hadn’t worn this costume for more than 30 minutes at a time. It was hot, heavy, and hard to see out of—but honestly, it was the most perfectly imperfect first cosplay experience. Every cosplayer who starts out clueless deserves that rite of passage.

Then something amazing happened: a gentleman walked up to Pax and me and asked if his kid could take a picture with us. We said yes, of course—and I was floored. A kid actually wanted a picture with me?! He thought we were the coolest thing in the world. That moment—the joy of bringing a character to life for someone else—was unlike anything I’d ever felt.

Later, Pax introduced me to the 501st Legion, a group of insanely talented Star Wars cosplayers. I asked them a million questions. Pax, being a Mandalorian cosplayer, started pushing me to make a kit too. I designed one, but something was missing. Star Wars is amazing, don’t get me wrong, but the fire just wasn’t there for me like it was for him.

Then in 2023, the craving to play a shooter hit me hard. Nothing sounded good—until I realized I hadn’t played Halo since before high school. I was grown, married, and hadn’t touched my favorite series in nearly a decade. So I grabbed the Master Chief Collection on Steam. The moment that theme music started, I nearly cried.

I dove into Reach again, and to my surprise, many of my Twitch community friends loved Halo too. For the first time in over ten years, I had a Halo party with friends I had made myself. Eventually, my dad even joined in. The man who had always crushed me at the game—I was finally matching him, even surpassing him sometimes. He kept saying how rusty he was, but we both knew how special it felt to play together again.

One night, while playing with my wife, I told her how much I loved the EOD helmet. She looked at me and said, “Why don’t you just cosplay your Spartan instead of doing the Mandalorian?” And it hit me.

I’m a grown man with adult money. I can cosplay my favorite thing in the world. My wife is a genius—she makes me realize things I never even think about.

And so here we are: the start of my journey to bring Spartan Matthews to life.


I told Pax right away that I wanted to make a Spartan cosplay, but honestly, I had no idea where to start. He pointed me toward the 405th, which he explained was basically the Halo version of the 501st. That gave me a starting point, but beyond that, I was kind of on my own. I made an account and needed a name. I tested a bunch of ideas. It took me a week to settle on using my middle name as my cosplay name. MATTHEWS WAS BORN!

I had never used a forum before, didn’t know anyone in the community, and wasn’t sure where to even begin. So I figured I’d just take it piece by piece and really didn’t know the etiquette for the community and didn't wanna bother anyone. I didn't know if it was rude to just DM someone so I became a certified lurker for an entire year in the community.

The first thing I did was fire up the Master Chief Collection and start grabbing reference shots of the suit. I went through carefully, noting down each piece I wanted to make.

Now, I know most of the people reading this are probably 405th members or cosplay veterans who already know their way around builds. BUT—just in case you’re not! I’m going to break everything down step by step: what each piece is, where I found it, and how I put it together and how the journey has been so far problems and all.

 

[Matthews 027]

Hey Y’all!

I’m Matthews, and this is my first ever Halo cosplay! For this build thread, I want to share everything I’ve learned so far—why I made the choices I did, how I figured things out step by step, and how I planned this whole thing. But first, let’s start with a bit of background and why I’m even doing this cosplay in the first place.

I’ve been gaming ever since I could hold a controller and form a halfway coherent thought. The first game I ever played was Halo 3 with my dad. From the very beginning, I was hooked—I had never seen anything like it. That game sparked my love for shooters and became this special way to spend time with my dad.

Then 2009 rolled around, and the Halo: Reach trailer dropped. My dad, his friends, and I were beyond excited. In 2010, he took me to the midnight release at GameStop. I was only nine years old, so staying up until midnight alone was the coolest thing ever—but going to the launch of a brand-new Halo game? Unreal. We were there for hours, hanging out with other fans, joining the activities the employees had set up, and then my dad walked out with that massive Legendary Edition box.

We got home, unboxed it, and then I saw the statue. Up until that point I thought Master Chief was the coolest Spartan ever—but then I laid eyes on Noble Team. Their armor designs were so unique, so different, and I knew instantly: that was the team.

Playing Reach with my dad, watching the campaign unfold—it shook me. I had never cried over a game before, never been hit that hard by a story. We played it for years on the 360, joined Halo parties where everyone would bring TVs and Xboxes, and it was just pure magic. Eventually, though, life got busier. I grew up, my dad’s friends drifted away, other games came along. But deep down, I always wanted that same kind of friend group my dad had built through Halo.

Fast-forward to 2022: I started streaming on Twitch and met my friend Pax. He invited me to my first convention in Kansas City, Missouri. We decided to cosplay together, and though I had never cosplayed before, I’d done theater and props in high school and thought, this can’t be too different, right?

I made a Reaper outfit from Sea of Thieves, flew to the con, and quickly realized… I hadn’t worn this costume for more than 30 minutes at a time. It was hot, heavy, and hard to see out of—but honestly, it was the most perfectly imperfect first cosplay experience. Every cosplayer who starts out clueless deserves that rite of passage.

Then something amazing happened: a gentleman walked up to Pax and me and asked if his kid could take a picture with us. We said yes, of course—and I was floored. A kid actually wanted a picture with me?! He thought we were the coolest thing in the world. That moment—the joy of bringing a character to life for someone else—was unlike anything I’d ever felt.

Later, Pax introduced me to the 501st Legion, a group of insanely talented Star Wars cosplayers. I asked them a million questions. Pax, being a Mandalorian cosplayer, started pushing me to make a kit too. I designed one, but something was missing. Star Wars is amazing, don’t get me wrong, but the fire just wasn’t there for me like it was for him.

Then in 2023, the craving to play a shooter hit me hard. Nothing sounded good—until I realized I hadn’t played Halo since before high school. I was grown, married, and hadn’t touched my favorite series in nearly a decade. So I grabbed the Master Chief Collection on Steam. The moment that theme music started, I nearly cried.

I dove into Reach again, and to my surprise, many of my Twitch community friends loved Halo too. For the first time in over ten years, I had a Halo party with friends I had made myself. Eventually, my dad even joined in. The man who had always crushed me at the game—I was finally matching him, even surpassing him sometimes. He kept saying how rusty he was, but we both knew how special it felt to play together again.

One night, while playing with my wife, I told her how much I loved the EOD helmet. She looked at me and said, “Why don’t you just cosplay your Spartan instead of doing the Mandalorian?” And it hit me.

I’m a grown man with adult money. I can cosplay my favorite thing in the world. My wife is a genius—she makes me realize things I never even think about.

And so here we are: the start of my journey to bring Spartan Matthews to life.


I told Pax right away that I wanted to make a Spartan cosplay, but honestly, I had no idea where to start. He pointed me toward the 405th, which he explained was basically the Halo version of the 501st. That gave me a starting point, but beyond that, I was kind of on my own. I made an account and needed a name. I tested a bunch of ideas. It took me a week to settle on using my middle name as my cosplay name. MATTHEWS WAS BORN!

I had never used a forum before, didn’t know anyone in the community, and wasn’t sure where to even begin. So I figured I’d just take it piece by piece and really didn’t know the etiquette for the community and didn't wanna bother anyone. I didn't know if it was rude to just DM someone so I became a certified lurker for an entire year in the community.

The first thing I did was fire up the Master Chief Collection and start grabbing reference shots of the suit. I went through carefully, noting down each piece I wanted to make.
View attachment 367446View attachment 367447View attachment 367448View attachment 367449

Now, I know most of the people reading this are probably 405th members or cosplay veterans who already know their way around builds. BUT—just in case you’re not! I’m going to break everything down step by step: what each piece is, where I found it, and how I put it together and how the journey has been so far problems and all.

Now, I know most of the people reading this are probably 405th members or cosplay veterans who already know their way around builds. BUT—just in case you’re not! I’m going to break everything down step by step: what each piece is, where I found it, and how I put it together.

For future reference, everything I’ve made so far has been printed on my Bambu Lab P1P—with the exception of my helmet.


We’re building the Mark V armor from Halo: Reach.

• Helmet: Standard EOD base helmet. It’s always been my favorite—and always will be. (EOD HELMET SUPREMACY!!!)
  
  
  • The visor is silver. I used to rock the blue, but the silver gives the helmet a cool, cold, almost menacing look that I just love. I did try the blue but youll see in a later post why i chose differently
• Left Shoulder: CQC. It used to be the Commando, but I swapped it out because I was worried about mobility with the chest piece. The CQC still looks awesome and id hope doesn’t get in the way when I raise my arms.
  
  
  
  
• Right Shoulder: Commando. Since there’s more room on that side and less conflict with the chest, I went with this. Plus, it’s a massive pauldron that just looks SO COOL.
  
  
  
  
• Chest: Collar/Grenadier [UA]. Inspired by Jorge's armor this thing makes you look like an absolute tank.
  
  
  
  
• Wrist: UA/Bracer. It’s chunky, it’s beefy, and it adds to that “walking tank” look I’m going for.
  
  
  
  
• Utility: Tactical/Soft Case. Okay, not gonna lie—the real reason I wanted this was for the pocket. Perfect spot to stash a water bottle or something small in case my wife (my usual handler at cons) can’t carry it. Also… it just looks cool.
  
  
  
  
• Knee Guards: FJ/Para. Technically meant for aerial units, buuuuut… they just look really cool.
  

When I started, I didn’t even have my printer yet. After some searching, I found that Galactic Armory sold a DIY kit for the EOD helmet. I measured my head, asked them if my size would work, and they actually test-fitted it for me before sending it out. About two weeks later, it arrived.

While I was waiting, I did a ton of research on how to build and finish the helmet. My color scheme for this kit is primarily black and orange with some heavy weathering, and since I knew I’d probably end up 3D printing most (if not all) of the armor, I wanted to learn everything I could about how to make it look right.

 

[Matthews 027]

I started researching primer, paints, and finishes. I’ve painted plenty of hobby kits and models—D&D miniatures, occasional Gundams, Warhammer—so I had a bit of experience with what different paints do and how to achieve certain effects and looks.

One thing I noticed about the Halo: Reach armor was how matte the colors are. No matter what color you picked, everything had that flat, muted finish—and I really liked it.

I spent a week visiting all sorts of stores, checking out spray paints and acrylics. Ultimately, I wanted to use spray paint so I wouldn’t have to hand-paint the entire kit. I’m very picky about how things look—especially something I actually want to use—and while I was new to cosplays of this scale, I figured it wouldn’t be a problem. I just needed a bigger brush… or better yet, a paint can.

That’s when I discovered a fillable, sandable primer. It’s a high-build spray primer that fills in minor surface imperfections, scratches, and gouges. It dries quickly, can be sanded, and creates a smooth, uniform surface for painting. While it’s used a lot in automotive, woodworking, and fiberglass projects, it’s also really common in cosplay, especially for prepping 3D prints.

Eventually, my package arrived: a huge box full of pieces with a sticky note from Galactic Armory saying they test-fitted it on a gentleman named Matt. Fitting, given the character—and weirdly coincidental.

I immediately got to work gathering my supplies: Bondo, JB Weld, latex gloves, and sandpaper ranging from 60 grit all the way to 800 grit, plus my latex, paints, and a super clear flat spray to seal the finished result.

I then took a week to assemble the helmet with JB weld, I applied it using my fingers while wearing a latex glove. It kinda helped me learn how smooth I got it and where I physically feel some gaps I may have missed with a spreader. I left each piece too dry and cured for two days in a well ventilated area where temperature wouldn't fluctuate too bad for the JB as it cured. This process piece by piece took about a week and to hold the top while it dried is my trusty cosplay belt. Its helped me hold four costumes together while they dried or needed too form and it worked perfect for this

AND WITH THAT IT WAS READY TOO SAND

 

[Matthews 027]

Next, I started sanding. The process was long: sand, prime, sand, prime again, fill gaps with Bondo, sand and prime some more… repeating and moving up through sandpaper grits until everything was smooth. For those who don’t know, Bondo is a two-part polyester putty used to fill dents, scratches, and holes on surfaces like auto bodies, wood, and fiberglass. It cures fast, doesn’t shrink, and creates a durable surface once sanded and primed. There are other ways of filling many others and I'm going to try two other methods on this kit as I go.

Now, I had a Dremel and a palm sander and figured they’d make the sanding process easier. Spoiler: they didn’t. I ended up adding scratches because (at the time, I didn’t realize this) my Dremel settings were too high, and I was pressing too hard with the palm sander. That friction caused the PLA to heat up, soften, and leave behind melted spots. If they had looked like natural scratches, fine—but instead they looked like some guy had been friction-welding plastic goop onto the armor. Not a good look.


That’s when I learned more about what I was working with. Galactic Armory uses PLA filament (Polylactic Acid). It’s a plant-based plastic commonly used in 3D printing because it’s easy to work with, prints at lower temps, and is even biodegradable. PLA doesn’t have a single melting point—it melts across a range, usually between 160°C–220°C (320°F–428°F). The sweet spot for printing is typically 190°C–220°C, which keeps everything flowing nicely through the nozzle.


And here’s the key takeaway:
DO NOT—and I repeat, DO NOT—leave your armor in a hot car or in direct sunlight for long periods.
PLA will warp, sag, or even melt.


Or, to quote the legendary DeltaAlphaZulu, 405th Regiment Officer: “Treat your armor like your baby and don’t leave it in the car.”

After the first general sanding, I set the helmet on a pole with a flared top so it could sit securely while I hit it with filler primer. Filler primer is great—it doesn’t just help fill gaps, it also reveals every flaw you thought you had smoothed out: print lines, seams, little marks you missed entirely.

Once the primer dried, I broke out the Bondo to patch up some of those gaps. Bondo cures chemically (not by drying) and usually becomes sandable in 15–30 minutes, sometimes even faster if you use the “Fast Dry” version. How quickly it cures depends on the hardener mix, how thick it’s applied, the temperature, and even the surface it’s on.

Because I had gone too rough earlier with the dremel and palm sander, leaving scratches and heat marks, I realized I had no choice but to sand everything by hand. So I started over—filling, sanding, priming, and repeating. I kept at it for a few days, slowly working it smoother each round. and I wont lie. this has been my least favorite process of the entire kit so far.

 

[Matthews 027]

I kept sanding over the course of a week, priming and adding Bondo, sand and repeat as needed. I definitely went a little over the top since it was my first time, and I just wanted to make sure I did this right—especially since I bought this helmet and really didn’t want to screw it up.

Eventually, I got it to a point where I thought it was ready for wet sanding. Everything was smooth to the touch all over. It didn’t even feel like a 3D print anymore—there was absolutely zero rough texture anywhere on the helmet. I even hit the inside a bit just to smooth out the JB Weld for when I put pads in later.

I brought the helmet and some sandpaper, sat myself on the edge of the shower, and went to work with finer grits. I did this about six more times, each with progressively higher grit, until it was such a smooth texture when wet that it honestly felt disgusting against my hand. That’s when I knew it was done.

After drying the helmet, I primed it one last time. I WAS FINALLY DONE WITH SANDING. 36 HOURS OF HAND SANDING—because I was paranoid it wasn’t good enough.

From what I’ve been told, most people do their first helmet entirely by hand sanding too, but lord… What a process. But lesson learned, and the palm sander and my dremel have become my best friends in crafting.

NOW IT WAS FINALLY READY FOR ITS FIRST COAT OF PAINT!!!!!!!!!!!

 

[Matthews 027]

As I did my research beforehand, I had found the metallic paint I wanted for the base coat: Rust-Oleum Specialty Metallic Silver Spray Paint. No glitter, just clean silver—perfect for my taste. Personally, I hate glitter in metallic paints. To each their own, but that’s the beauty of cosplay: it’s all about personal preference and what’s available. You get to make it your own. I can’t recommend it enough, to be honest. It has the perfect silver shine you could want. I plan to use it on a Magnum very soon as well!

Then, while at Ace Hardware, I discovered Rust-Oleum Chalked Ultra Matte Charcoal Oil-Based Acrylic Sprayable Chalk Paint. This paint was a literal godsend. It gave my armor exactly what I wanted: not shiny and new, like a freshly recruited Spartan, but scuffed, weathered, and battle-worn—the perfect look for my kit. The majority of my armor is black, and these two paints would become the base for the weathering and overall look of most of the build.

(I’m still hunting for an orange; the helmet didn’t have any, as I hadn’t planned it for this stage yet.)
Finally, I knew I wanted to do some weathering on the helmet. There are tons of techniques, but I settled on one I found thanks to YouTuber and cosplayer Vault Fox. She made an amazing video on weathering a Mandalorian helmet, which I followed closely:
Vault Fox Weathering Tutorial

Vault Fox—if you somehow ever see this, thank you! Your videos helped shape how I approached weathering my kits. She uses Vallejo latex drawing gum, which you can brush on, paint over, and then gently rub off to create weathering. HOW COOL IS THAT? And the 45ml bottle is only about $7—I still have almost a full bottle. 10/10 purchase in my opinion.

This weathering effect I believe is called paint chipping and I love it so far.
So we grabbed the silver paint, and my Nana (my grandma), who is very skilled with spray paint, handled the first coat and showed me how to spray properly and avoid drips as I did the next two coats. This was a bright March afternoon, and the mirror shine I got off the helmet after it had dried was amazing. I had to wear sunglasses when I picked it up and looked it over.

At this point, the paint was technically… dry to the touch. It’s recommended to wait and let it “fully” dry for 24 hours, BUT I WAS THIS FAR IN AND HAD THE PAINT READY. So I went ahead with the weathering effect along the spots I wanted, then put the helmet back on the stand and started hitting it with black.

I was starting to see my helmet I’d always worn in-game come to life, and I knew then that this was going to be the coolest thing I’d done so far.
Then I went over the edges of the edges of my helmet here and there with a sanding sponge and lightly got the black off the edges which gave it this great heavy weathering effect I personally enjoyed and with that the helmets base colors were done and it was time for small details and then a wash and sealant.