Foam MJOLNIR Mark VI - Halo 3 Foam Build Thread


New Member
Hello all, my name is Daniel, I go by Mirrorbright. I am close to completing my first Halo build, and I'm excited to finally wear it to cons! Master Chief is the first costume I ever wanted to make, and I'm so happy to finally build his armor from my favorite Halo entry: Halo 3 (don't @ me). I should have been posting here through the entire build, so I'll pretend that's what I'm doing. I'll be updating this thread with photos and descriptions over the next few days.

This isn't my first time working with foam; I have done a few Overwatch cosplays. I used the following patterns:
Armor: Halo 3 - MJOLNIR Mark VI - Standard LD
Helmet: Halo 3 Mark 6 Helmet by Rainyfire
Gloves: Halo 3 - Mark 6 - Master Chief Armor Set - No Helmet by moesizzlac

Most of the armor will be foam, except the hands and helmet, which will be printed in ABS.

Here are a few finished shots, as a teaser:

VV5A5572 (1).jpg
VV5A5565 (1).jpg

You can see more finished shots of the build on our Instagram. Most of the pictures I post here will be WIP pictures. You can also checkout this YouTube series I did in making the costume: Mirrorbright Cosplay - YouTube
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New Member
Now to add details. Since the pattern is low detail (as designed), I used screenshots, the 3d models, and even booted up TMCC to see what needed to be added. I then drew on my existing patterns what I wanted to add, and used 2mm foam to add to the construction.

Bonus points awarded if you immediately know what sections of the armor these belong to.

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New Member
Oh I made the boots too. Instead of gluing them to real boots, I made them as boot covers. So when these eventually get upgraded, I'll be able to use the same pieces and won't have to remake.

They slip on, and are held in place with elastic bands.

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New Member
I really really really wish I was better at documenting things. There are so many steps I can't account for in adding the details.

Sunken lines were made by scoring the foam, then using a heat gun to open them up, like you can see on the biceps.

Also something else I tried on this build was using foam clay (also from HD foam) to fill in seams. I think it worked pretty well.


New Member

I did some experimentation, and found the best paint job was a base coat of gold, then a light top coat of Italian olive. Here are the specific products I used:

Italian Olive:

But first, I sealed the foam with our good friend plastidip:

Oh before that, I used a Dremel to cut into the foam for battle damage.
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New Member
Now for my "Baby" of the build: the 3d-printed helmet. Printed in one piece out of ABS on a CR10-S Pro v2. The STLs are listed in the first post in the thread.

I found this was the best way to print the helmet (there were several failed prints). I also printed this without an enclosure, so there were some separations in the lines.



New Member
I use these two products on most of my 3d-prints:
Filler Primer:
Spot Putty:

After a round of sanding, I'll spray the entire helmet with filler primer. This will help fill in some of the printed lines, and highlight areas that need more help. For large defects or gaps, I'll use the spot putty.

I probably did this for like 10 rounds until I was happy.



New Member
The visor for the helmet was fun, because it's not something I have ever done before. I had created a small vacuforming machine using the instructions by Punished Props, so I wanted to use it to make the visor.

I 3d-printed the buck using the visor 3d-print, and turned on the support angle to 0 so supports will be printed at all angles. I'm sure there's a better way to do this, but I didn't have access to the original model to modify it the way I should have.

After printed, I finished the buck using filler primer again, and sanded it down so it was fairly smooth.


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