M4 Gun

Prop Breakdown

Tatiana Castanheira


Tatiana Castanheira

3D Artist


Hi! My name is Tatiana and I'm a self-taught Junior 3D Weapons Artist.
My current goal is to find my first gig in the 3D industry so, to help me polish and develop my skills.


I used 3Ds Max for blockout, high and low poly, baked and rendered in Marmoset and textured in Substance Painter.


I can lose myself in gathering references, but this step is one of the most important. With good references, I can learn how the weapon works, how it was made, where it has wear, dirt, oils and so on. I use google to look for references everywhere I can look for weapons online stores so I can see them piece by piece.

Websites like https://www.midwestgunworks.com/ and https://www.gunbroker.com/
Also, Youtube channels like 3DGunner, Thomas Schwenke and Forgotten Weapons show how the weapon works.



I start my blockout with an image reference with good quality on the background. I then create a box that had the real-life dimensions of the weapon and lined it up from the tip of the barrel to the end of the stock.

That way I know the weapon is as close to real-life proportions as possible. The blockout geometry I create during this stage is used for both the highpoly and the lowpoly. I also prepare some floaters for the high poly during this stage.

This way I mostly only have to add support loops and chamfer modifier to the high poly and clean some extra in the low poly while keeping the same forms. I also model a bullet to have an idea of all the measurements that are ok with the magazine, barrel and muzzle break.



For the high poly, once the blockout geometry is completed, I have to add support loops and turbosmooth modifiers carefully to always have the same edge thickness in the appropriate places of the gun. For instance, plastic surfaces often have “fatter” edges while metallic edges are usually sharper.

Sometimes with more tricky parts I use the chamfer modifier and add some more support loops and turbosmooth so it looks cleaner since it’s metal I don’t want any surprises in the shader, sometimes I change to a different material like aluminum to see if any pinched edges are happening. In the end, I give different color materials on floaters to be easier to texture on Substance using ID maps.


Low Poly and UVs

For the low poly, it’s time to collapse and connect and even cut extra edges, merge polygons that we don’t see and are not animated and mirror identical parts to optimize Uv space.

With this gun, I did that with the plastic stock, plastic handguards and rail shroud/hand-guard. I open my UVs while making my low poly and by the end, I make sure everything is straight and clean applying checker material on the weapon to see if there are any strange distortions.

I make the UVs bigger on the parts that the camera will see the most like rear sight and sights, the parts you don’t see I make them the smallest I can. I still do UVWs all manually but will soon use UVW plugins to speed up the process.



Since I have two different texture sets, I name each part of the texture set with the sufix_low and make sure that the high poly has a correspondent name but with the sufix_high.

Once that’s in place I create a new max file, a baking scene, in which I collapse the turbo smooth modifier of my highpoly geos and then I am ready to export the objects of each texture set to marmoset for the baking stage.

I check each part to see if any errors occur, check the cage offset all over the model and if some baked parts are not in the correct position or distorted I fix them using “paint skew”. I bake my normals, curvature, ao, and materials ID’s with Marmoset and the rest in Substance Painter.


I have a lot of fun during this stage, it’s during this stage that the weapon really comes alive. When I was looking for references for the gun I grabbed all interesting reference images for texturing like scratched parts, where the dirt goes, oils, and color variations that caught my eye.

I textured with Substance Painter, for metal rough shader and change my environment to Tomoco, that way I don’t have any environment light colors interfering with my textures. I also opened the Marmoset scene using Smashed Windows with a fill light so I could be texturing and exporting the textures to see how the weapon could look in the render, since I work in substance paint with 1024 or 2048 sometimes I can’t see the little details very well.

I start with a fill layer without anything on it just very rough and completely black. This way if I miss something or if is there any holes that are left behind it will just look like a shadow or easy for me to catch them.

Next, base material color, roughness base I want, make it metal and height 0, for this one, I add filter “matt finish powder-coated after with another fill layer adds some height variations with 3D Perlin noise fractal not much, time to start with color variations… fill the layer with a slightly lighter violet in overlay blending mode around 40% mask it black and use clouds grunge, another color variation this time just with a lighter color from the base material using Lgt blending mode 13% mask and add grunge map.

I tried a few variations until they looked more like the reference I had. I did the same with roughness variations, adding grunge maps and mixing blending modes. For the wear I started with the simple metal edge wear generator, more grunge maps on top of it with multiply/overlay/subtract blending modes and then by hand with a brush I scratched out what I didnt want, I painted the wear I wanted in a specific part with brushes, usually “dirt2”.

For dirt, I was using a dirt generator mixed with grunge maps and again with a brush to clean the excess. The same thing with oils, I tend to go around a few smart masks and test them to see if any interesting thing happens in the area I want, cleaning them and shaping them with brushes. I always add since the beginning a little sharpen on top of everything in passthrough mode.



Made my renders in Marmoset Toolbag 4, for the Sky I used Empty Warehouse HDRI from Poly Haven and added a few extra fill lights and rim lights to the scene. For my main render camera changed the field of view to 20 in perspective, tone mapping to “Hejl”, which gave a little extra contrast center 0.612 and sharpen 0.036.

No grain or vignette. Render options I turned on Use Ray Tracing, all options I could to high, Shadow Quality to Mega, Use Cascades on also Local Reflections.



It’s a great pleasure to create 3d guns and at the end of the day, it is a very big challenge The pipeline I used makes it easier for me to create these things because the blockout stage is very involved.

I detail it as much as possible and make sure is round and all of that. Setting up a good foundation like that, in the end, makes life easier and it makes the entire process very approachable. Planning is the key. Feel free to pm me in the ArtStation with any feedback or questions.

Special thanks to Hugo Morais and Joakim Larsen, without you, I wouldn’t ever have done anything like this.

Thank you so much for this opportunity Games Artist! I am flattered to make this article for you.