RobotChicken’s Mjolnir Mk VI Forearm Armor Detail Parts

The Mjolnir Mk VI forearm Pepakura armor model lacks a prominent feature at the antecubital space (elbow pit). This feature is completely absent in the normal detail models, and although represented in the High Detail (HD) models, it’s very inaccurate when compared against reference photos:






I chose to create this detail such that the armor pieces more-closely resemble their appearance in photos. Since I’m better with computers than I am at sculpting, and producing a Pepakura file of the detail would enable it to be scaled more easily, the obvious option was design a model for pepping (or 3D-printing for those of you with access to such a magical device). TurboCAD Mac Pro was used to create a 3D model from many wonderful reference photos provided by SirPalesAlot (thank you!).




Four versions of the detail were created with incremental degrees of complexity for compatibility with the existing Mk VI forearm models:

ND (Normal Detail) Mk VI Forearm by ROBOGENESIS
Height = 381
Width = 193
Depth = 180
Scale = 86.0
ND Mk VI Antecubital Detail


MD (Medium Detail) Mk VI Forearms by flying_squirl
Height = 290
Width = 342 (model includes both forearms)
Depth = 134
Scale = 2.272698
MD Mk VI Antecubital Detail


HD (High Detail) Mk VI Forearm by nugget
Height = 330
Width = 177
Depth = 149
Scale = 465.522422
HD Mk VI Antecubital Detail


UD (Ultra-High Detail) Mk VI Forearm by SirPalesAlot and RobotChicken
Height = 304
Width = 169
Depth = 135
Scale = 1.0
(Antecubital detail is integrated into the forearm model.)


3D (3D Printer) Mk VI Forearm by SirPalesAlot and RobotChicken
Height = 304
Width = 159
Depth = 135
Scale = 1.0
(Antecubital area is flat for attaching a 3D-printed detail part.)



Scaling The Model

The detail parts are drawn at the same scale as their associated forearms, so simply enter the same Scale value for the antecubital detail model in Pepakura that was used for the forearm model and the parts will print at the correct size. Each of the detail models includes the forearm's perimeter polygons for interfacing with the detail. To avoid having to modify the forearm unfold, these modified perimeter polygons also include the full forearm part they're associated with. This means you can simply swap out forearm parts with the detail parts without needing to get your hands dirty with any changes to the unfolding (unless you want to).

After resizing the detail model to match the scale of your forearm, the page layout will probably need adjusting. The detail models are all drawn for the right forearm, so you will need to Mirror the model in Pepakura (invert it) to print parts for the left forearm. Each file is set up with Edge IDs turned off (the reason why should become obvious if you turn them on), and due to the parts size I’ve set the Lineweight print setting to 1 so they print clearer (hairlines allow for more precise folding and cutting). You’ll see in the photos just how small the pieces were for my child-sized build and I was able to successfully assemble them (tweezers and magnifier lamp were indispensable), so if anything it should be a bit easier with larger, adult-sized, parts.

Step 1: Front Assembly

The first area that should be assembled is the front because it contains flaps which are not accessible for gluing after surrounding areas are built. (You'll probably know how I came about that conclusion...) This starts out with the bottom and two side pieces:




Glue the bottom flaps first, then fold up the back to glue the back flaps:


Next fold down the top and glue its flaps:



After the lower front "pocket" is assembled add the top part:


This should be attached at the front first for aligning the small forward edges:


Again, I use a tweezers for clamping small corners to ensure nothing shifts while the glue sets:


Then attach the back edge and interior flaps for the top concave curved area, finishing with the back side corners:



To add the raised edge detail seen in game screenshots, I cut three strips of cardstock at the same width as the top "frame":


The sides get glued on first:


Then the back strip is added, making sure it conforms into the corners of the side strips:


Lastly it's trimmed even with the outside edges:

Step 2: Sides Assembly

The next area that should be assembled are the sides, which can be a bit of a challenge due to their many small parts towards the front. Start by attaching the completed front assembly onto the front of the main body part:




Assemble the two side parts before attaching them onto the main body part:








For easier finishing of the interior detail parts after hardening I opted to build them separately as in the HD file, but with the UD parts rather than the HD parts. That's why you see the interior area with a full bottom face instead of holes for attaching the interior detail parts. This meant combining some of the HD parts with some of the UD parts and customizing their unfolds so they worked together. Unfortunately I messed up and failed to put a flap on an edge where a UD part connects to an HD part. No problem - it just meant I needed to add some scrap cardstock to the inside for holding the corner together on each side:






Next comes a lot of small parts for building the front "torpedo" shapes. Starting from the back, glue each part on the vertical edges only:






Once all the vertical edges are glued, close up the horizontal top seam to finish it off:




Attach the adjoining forearm faces around the perimeter before adding the antecubital detail to the forearm. Otherwise you will have it extremely difficult reaching inside to glue the flaps. (Again you can probably guess how I came about that conclusion and why I don't have a photo of the detail area with surrounding parts attached before adding to the forearm.) But with difficulty, I managed to get them added anyway and they look like this:




You might notice in that last photo that the front area is smoother than the previous photo. That's because I decided to revise their unfold when the parts didn't fit the forearm opening on the first time around. The File Archive downloads are updated with this revised unfold which makes it easier to align the edges and also yields a quicker build due to fewer parts.

Step 3: Interior Details

As mentioned in step 2, I opted to build the interior details separate from the main assembly for easier access during later hardening and finishing. The center "box" is pretty straightforward:




Next I built the rounded block, starting with its concave top area:








Next the sides are put on, starting from the back:








Lastly it too gets attached to a parts holder for handling during hardening and finishing:




The final interior detail part is a square ring with rounded tops. This was quite a challenge at child scale, and the Silhouette Cameo I use for cutting out parts had fun mangling up the minuscule flaps. (I need to get a new blade for the machine.)






Again I used clamped tweezers for holding flaps while the glue sets to ensure tight square corners:




I did my best at getting the corner parts installed, but because this part is so tiny for me it didn't turn out as well as a larger version would. No concern, though, as I can easily "fix it in post" with Bondo.




I made a frame from mat board and attached it on the backside to help support the parts holder while during hardening and finishing:

Reserved for new assembly photos.

Reserved for new assembly photos.

Reserved for new assembly photos.

Reserved for new assembly photos.


If you end up building these for your armor, be sure to post photos of them here. I'd love to see how they turned out!

(Reserved for my own photos of the finished detail.)

Answers to Questions

What thickness of mat board do you use?
As far as I know, "mat board" is available in only one thickness, which is about 1.5mm thick. I've never seen it with other thicknesses. You can adjust the thickness down by peeling off layers as it's comprised of several layers of paper (see photo between steps 3c and 3d), or you can increase its thickness by gluing more layers to it such as cardstock or mat board depending on the desired thickness. Here's a link to the wikipedia page describing mat board: http://en.wikipedia.org/wiki/Mat_board

Thanks for the walkthrough! I am going to atempt this when i start my armor.
Quick question : With mat board since i have never used the stuff is there a general thickness that you use if there is varying thickness to it or just any type stuff will do?
I was thinking on useing mat board for some of the detail parts on my helmet and various armor pieces after watching your armor build.

That is some serious and awesome fine pep work mate.

This is just insane....Great job...and thanks for sharing with us all the steps...

morkar78 said:

This is just insane....

Click to expand...

"I'm not insane, my mother had me tested."

Nother question... with how small the piece is and this is going to sound like a dumb question do you think it would be easier to construct this out of regular printer paper instead of cardstock for the sake of the really really small bends/folds of the two pointy bits? or would this make the piece too weak once you get to the resin rondo steps? Because for me these pieces are only 2" long for my armor witch compared to yours is freakin huge but to me its super tiny =/ I dont think i could do that detail on a child suit.

I think the pointy ends maybe could be made from regular paper instead of cardstock since they're so small and the vertical glue joints should hold them rigid enough to not "collapse" when applying resin. The straight quarter-round tubes on the sides might also be made from paper for smoother curling than I could achieve with the thicker cardstock at such a small scale (it kept wanting to crease or "dent" instead of curling smoothly). In hindsight, I might have made those areas from regular paper (or at least thinner cardstock) - I just didn't think of that at the time. I figure I'll just smooth them out better during finishing. However, I definitely wouldn't build the whole detail piece from regular paper. It wouldn't be strong enough for hardening. Yes, mine parts are pretty tiny, so that's why I mentioned how if I could build them at my small scale (and have the photos to prove it!) then they should be easier at a larger scale. If you really want to see small, print at a scale of 1 (the scale I used).