How to Model and Texture a Realistic AK-74 Using 3ds Max, ZBrush and Substance 3D

Introduction

Hi! My name is Oriol. I am a 22-year-old 3D Artist based in Barcelona who has an infinite passion for games and films! Since I was 4, I knew I wanted to make a living out of video games, but I did not know exactly how to get started. My goal was to learn how to code, but I realized I was not cut out for that in the second month of coding.

At the age of 18, I got into a 3D vocational education course, and thanks to Gerard, one of my teachers, I realized 3D was the way I wanted to contribute to the creation process of video games/films. At the start of my Art Degree, I was lucky enough to have another teacher, Marcos, who taught me a lot about different workflows and introduced me to ArtStation.

Once I opened it for the first time alone at home, one single artwork changed my life. It was Thomas Butters' SKS for Rust. I did not know how it was possible to create such artwork with 3D software. That same moment, my quality bar raised; I wanted to reach that level, and since that moment, I started taking my 3D journey more seriously.

During this learning journey, I have met lots of amazing artists who have helped me shape the way I work. One of the most relevant is Juansa Torres, who's been one of my 3D modeling teachers and now a friend who has helped me and guided me a lot throughout my 3D art journey, and has taught me a lot.

I've failed a lot, and I've created tons of models. Thanks to repetition, hard work, dedication, and help from some amazing artists who surround me, I reached the point I'm at today. Right now, I'm finishing my master's degree in 3D modeling at La Florida Universitària, while being a 3D Hard Surface Intern at Hunting Souls. I can't wait to see what's ahead in my professional career!

The AK 74 project started as an assignment for my master's degree. I could have chosen any other weapon, but I decided to go with the AK-74 because it was the successor of the first weapon I had ever modeled on my 3D journey, the AKM. 

The AK-47, AKM, and AK-74 have too much historical and cultural relevance to be dismissed. It's also a weapon that contains at least three different materials with various wear and tear levels, which makes it a really interesting weapon to texture.

My goal with this project was being able to showcase my weapon art skills and to focus on the small details that make any kind of historical weapon interesting to look at.

Reference Gathering for the AK-74

When searching for references, I noticed that there are many different AK models and different manufacturing places. Also, around half of the AK-74 parts are shared or compatible with the AKM. The main difference between the models is the caliber change from 7.62x39 mm to 5.45x39 mm.

Knowing all of this information, I ended up with this reference board, where I studied different kinds of versions for the AK-74 and AKM compatible parts, a variety of stocks and handguards with different wear and tear from different AK models, and finally, all of the AK-74 internal and external relevant parts to learn how the weapon works and to be able to model them properly:

Usually, I gather references that are not added to the final PureRef, as I get lost when I have too many images on the reference board. Here's the folder structure with more references to various AK models (~1000 refs) that I often come back to look at:

To find references, I will always try to find the following things: a YouTube disassembly video and a review of the weapon, reference packs that include the weapon I'm modeling (even better if it includes more than one weapon that you want to model), auction sites, and the weapon parts list, either from a random forum or the weapon manufacturer, to search them later.

Modeling

When modeling, I use both 3ds Max and Blender. Both are amazing pieces of software, and the same workflow can be followed with different paths. Although I used 3ds Max for this weapon, I'll explain how the workflow applies to Blender. 

When speaking about realistic games, almost every good 3D prop/weapon focuses first on the high-poly and uses the low-poly as a method to project the high-poly. Focusing on adapting the high-poly to the low-poly will most of the time bring constraints to the creativity of the artist and the final look of the weapon. My personal workflow mainly focuses on:

• Getting a "mid-poly" done that focuses on the shapes, not on the topology.
• Taking the "mid-poly" to ZBrush and polishing it until the desired look is achieved.
• Taking the decimated ZBrush high-poly and adapting the previous "mid-poly" mesh to the ZBrush high-poly shape, adjusting the topology to the proper one to create the low-poly.

As you can see, the "mid-poly" mesh is full of N-gons and has a totally different handguard shape than the low-poly. The topology is mostly reduced, and there are only a few things in common with the low-poly mesh. How does the ZBrush polish workflow work? I'll do a small demonstration of how I used it for the AK-74 with the following piece:

I always start with the mid-poly. To create this shape, I'll add a cube, a cylinder with enough topology, and a hexagonal cylinder on top.

For this kind of shape, I always try to add a similar topology as the one I would like the low-poly to have, so later on, I don't have to clean up as much geometry. If I added a 72-faced cylinder instead of a 24, I would have to clean up a lot, and I want to be as fast and as clean as possible.

You can either do the Booleans on 3ds Max or on ZBrush with the Live Booleans feature, and it will make no difference at all. I will perform the Booleans in 3ds Max to showcase some common issues that can occur when using this workflow. Here's the mesh with the Booleans applied:

If I triangulated this mesh, which looks fairly nice and opened it on ZBrush, I would have a problem. ZBrush does not understand hard edges or smoothing groups. The mesh would simply look like this:

If I applied the Booleans directly on ZBrush, the story would be different, but on more complex shapes, I like the second option, which is applying the Booleans on 3ds Max/Blender and using the feature Turbosmooth. It looks like this:

What basically the checkbox on the modifier does is look for the smoothing groups and apply a crease automatically where these change. It looks awful right now! The problem we're having is pretty simple: every time we subdivide a face with its edges aiming at an angle greater than 180º from one to another, the Subdivision Surface/Turbosmooth gets confused and produces the artifacts we're seeing in the image above. So to solve it, I'll add some simple geometry that will get rid of the problem, like in the following image:

I don't mind at all leaving N-gons, as they'll get solved by the Turbosmooth/Subdivision. Every mesh, when subdivided, becomes a quad mesh, and to get to ZBrush, we just need that. The mesh should look like the following image when subdivided with the Turbosmooth by smoothing groups:

As you can see, the borders now are super clean thanks to the amount of topology we have! How do we replicate this preparation to ZBrush in Blender? Pretty easy! Instead of adding a tick on a modifier, we will have to first mark the sharp edges, crease them, and then add the Subdivision Surface modifier!:

Once the mesh is properly adapted, as shown above, I'll send it to ZBrush, where I'll dynamesh it. When DynaMeshing, we have to take a close look to see some artifacts that DynaMesh can produce, like bumps and dented corners. To avoid those artifacts, you need to make a higher-resolution DynaMesh. Here's a demonstration of a good and a bad DynaMesh:

Once the dynamesh is performed, I like using the polish crisp edges on the deformation menu and the Morph brush to adjust the edges as I please. I usually add small details if needed, like dents or bumps.

The high-poly mesh has been done, now I'll use the ZBrush decimation master tool to lower the topology and be able to handle it more comfortably on 3ds Max/Blender. Here's a comparison of the decimated vs the non-decimated version of the mesh:

Adapting the mid-poly correctly to the ZBrush mesh is not hard. If the mesh has been heavily modified on ZBrush, a manual retopology is recommended. If it's something simpler, like Booleans or bevels, applying them to the mid-poly mesh is not as time-consuming. Here is how I would approach this low-poly:

That's my main high-low modeling workflow. The UV mapping, baking, texturing, and rendering would follow! I added some of the details of the AK-74 on ZBrush, like the grip pattern, which was later baked into the low-poly. The entire weapon was modeled using this workflow.

Some more views of the high-poly on Z:

There are variants for the shown workflow, one of the most popular being the Simon Fuchs Mauser tutorial and the Dylan Abernethy Writing Machine tutorial (Maya workflow). All of them work and are different ways of achieving the ZBrush polish result. I ended up picking some bits from here and there and adapted the workflow to my needs.

UV Unwrapping and Packing

One of the main goals when modeling the AK was to be able to generate close-up images and maybe create some variants in the future, so I had to be conscious about how I distributed the UV maps:

The AK has various parts that vary from model to model, these being mainly the stock, the handguard, the mag, the grip, and the muzzle, each of them being separated by different UV maps. I wanted to preserve a similar amount of Texel Density from texture set to texture set, which was the main reason for the resolutions chosen. The average texel density is 103 and varies by about 20, with the lowest map being 83 and the highest TD map being 123:

To ensure the UV sets were properly unfolded and packed, I used RizomUV and UVPackmaster, which have the best packing features I've seen in a while. If needed, I manually pack some of the UVs.

Texturing

For the wood texturing, I made the base stripes using a technique I saw at the 80 Level SKS article and the Dan Kenton revolver tutorial. I projected the Lines on the high-poly model to get a higher definition. I started drawing as well some of the handguard stripes when I disliked the projection. Once I finish detailing the lines, I bake the stripes to the low-poly via the Base color channel on Marmoset Toolbag. In the following video, I work on the handguard stripes.

I added an anchor point to the stripes' base and created two different color bases. When texturing non-metallic materials, I always like following this order: Base Colors, adding Color Variation, adding the Normals and Gloss, and adding Surface Imperfections.

Lastly, final touches and Ambient Occlusion. The wood for me is a really hard material to nail. I had to give it various iterations and phases of feedback to reach a point where I was finally happy with it.

The same goes for the stock:

For the AK metal, I wanted to achieve a half-painted, worn, and a bit rusted AK. For that, I created three materials and merged them with paint brushes. One material for the rust, one material for the paint, and one last material for the grease. The rust acts as a paint brush, so I can paint it as I please:

The same applies to the grease, which is on a separate paint layer. I do believe that something that makes a model unique is having hand-painted detail. Hand-painting grease or rust that generators or fill layers with masks definitely won’t give you. I encourage you a lot to use stencils/brushes for your detailing! Here's a breakdown of the whole barrel texture.

For the receiver, upper receiver, sight, and muzzle, the texture structure looks the same as the barrel, with the main difference being that I did not want a hard contrast. I felt it was more appropriate to play with subtle but noticeable color variation. The receiver zone also plays a lot with some more aggressive scratching, like the one on the firing selector or the bottom scratches.

One detail I always enjoy texturing is the fonts. The little serial numbers, the firing selection letters... The AK fonts have a beautiful depth that makes them look unique on 3D models. To be able to achieve the desired result is as easy as writing the text in Substance 3D, adding Height, a blur, and a High-Pass filter.

I also set an anchor point on the numbers folder to later fill it with the color I want. I also added a subtract to the color layer to add a bit of wear to the paint. The process is shown in this video:

The last materials I textured were the plastic grip and the mag. The grip was the easiest texture to pull. It was a base plastic with Color Variation, Normals, and some Roughness variation. However, the mag texture was a bit more complicated than that.

The process was similar to the wood I created for the stock and handguard, but I had to get more creative to create the magazine transition. I ended up painting the stripes this way:

As I've mentioned, the texturing process was similar to the wood:

Rendering

Rendering has to be one of the most important parts of the project. I wanted simple studio renders for the AK, but at the same time, I wanted to add something that introduced the weapon well. So I used the BigMediumSmall Special Ops rig.

The scene setup was super simple, as it's only the soldier posed with my weapon. The rig came with several poses, which made it super comfortable for renders:

The rest of the render was a white scene with a plane, an HDRI, and a couple of lights. Not much more is needed for what I wanted to achieve.

One thing that I like to do is add only very little grain on Marmoset Toolbag and add the grain, vignette, and color grading in Photoshop. I have a lot of control over how I want it to look:

Some of the final renders:

Conclusion

With this article, I wanted to showcase a cool and appealing workflow, the things I look at the most when creating a prop/weapon. I hope you found some of the information you read cool, and I really hope you learned something from this article.

I learned a lot during the creation process of this asset and I could not be more thankful to Pascual Hernandez and Jorge Falcón for all the feedback they've given to me during the project, to my master's degree at La Florida Universitària for giving me the platform to meet them, and to Gerard, Marcos, and Juansa for giving me the drive and orientation when I needed it the most.

I believe that passion is the fuel of joy and success, and I also believe that time and dedication combined are the source of improvement. If you have those three and never stop creating art, you'll be unstoppable!

Thanks, 80 Level, for this opportunity, and thanks for reading!

Oriol Salom, 3D Hard Surface Artist

Interview conducted by Gloria Levine