How to model and texture a biohazard barrel | Blender 4.1

This video shows how to create a 3D model using Blender 4.1. You will learn how to model, UV unwrap, and texture a barrel using Blender 3D. The final render was done in Blender 4.1.

Modeling

I will begin by using a cylinder

I set the origin to the 3D cursor

I rescale the cylinder to resemble a real-world scale of a metal 55-gallon drum – that is, 34 inches tall and 23 inches in circumference

In edit mode, I add four horizontal edge loops

I move the top and bottom edge loops toward the top and bottom of the cylinder

I then space the other two edge loops out in the center of the cylinder

I add a bevel to these two edge loops to match the size of the top and bottom faces

I select all four face loops and scale them out along their normals

I select the outer edge rings of these extruded faces and add a small bevel

I inset the top face and extrude it down along the Z-Axis

I add the same bevel to the new interior edge

I add a new edge loop close to the inset faces

I add horizontal edges between each of the extruded sections and move them close to the edges of the extrusions

This will keep those areas sharp

In object mode, I shade the barrel smooth

I add a weighted normal modifier to clean up the shading issues and apply it

I add a new cylinder, scale it down, and move it to the top of the barrel

I move it to the front of the barrel and make sure it intersects with the top of the barrel

I select the barrel and add a Boolean modifier with the operation being difference and the object being the smaller cylinder

I apply the modifier and hide the smaller cylinder

In edit mode, I delete the internal face

I select the edge ring and add a small bevel

I add another weighted normal modifier and apply it

In edit mode, I select the top edge loop and duplicate it – scaling it along the X- and Y-Axis

I scale the edge to add some faces

I select the face loop and extrude it up along the Z-Axis

I select the inner and outer edge rings and add a small bevel

In object mode, I shade the barrel smooth

I unhide the smaller cylinder and scale it along the Z-Axis

In edit mode, I inset the top face and extrude it down along the Z-Axis

I also add a bevel to the edges

I add two edge loops – one towards the top center and one toward the bottom center to keep the edges sharp

In object mode, I shade the cylinder smooth

I now repeat the process for the smaller hole toward the back of the barrel

UV Unwrapping

I split the viewport and open the UV mapping workspace

I select the horizontal edges and an edge down the back of the objects and mark the seam

I then unwrap the objects onto one UV map

I select the sides of the barrel and rotate them 90-degrees

I select all of the islands and use the pack islands option – making sure to deactivate the rotate option

Texture Prep

I make sure to apply all the transforms

I make sure all the faces are facing the correct way

Textures:

Metal 026: https://ambientcg.com/view?id=Metal026

Metal 024: https://ambientcg.com/view?id=Metal024

Metal 002: https://ambientcg.com/view?id=Metal002

Poison Signs: https://www.vecteezy.com/vector-art/90746-sign-of-poison-vectors

Leaks Texture: https://www.cgi-textures.com/p/16459/leaks-texture

Abstract Painting: https://unsplash.com/photos/purple-and-white-abstract-painting-dmJuppvEZu4

Gray Concrete: https://unsplash.com/photos/gray-concrete-surface-f-UkGU8GcWo

I will be using Affinity Photo to make some changes to a couple of the textures but you can use whatever software you have access to

I start by cropping the signs to select the one I want to use

I then use the selection brush to select the white background

I use the Backspace to delete the background and then deselect the image

I open one of the grunge textures I’m using

In order to adjust the color, I go to Layer > New Adjustment Layer > Levels and change the selection to gray to achieve a black-and-white image

I also increase the black level

I export the image as a PNG

Back on the sign, I add this grunge texture to a new layer

Using the move tool, I can scale the texture

I drag the grunge texture onto the sign layer to make a clipping mask

I select the grunge layer and change the blending mode to linear burn and lower the opacity

I export the image as a PNG

I also make a normal map for this image – I already have a tutorial showing you how to do this

Texturing

I split the viewport again and open the shader editor

I select the inner faces and bottom face of the plugs and assign a material to them

I select the rest of the barrel and add a new material

I select the central faces and add a third material

Texturing (Base)

I will be using the node wrangler add-on

I make sure I am in material preview mode

I reselect the main barrel texture and import the textures using CTRL + SHIFT + T

I increase the scale of the texture

To change the color, I add a hue-saturation-value node between the base color of the texture and the principled shader

Since I want a dark blue color I change the hue to 290, saturation to 83, and the value to 0.8

I drag in a grunge texture and add a mix color node

I connect the grunge texture to the b-input and the hue-saturation-value to the a-input

I change the factor of the mix color node to 1

I connect the mix color node to the base color of the principled shader

I connect the color of the grunge texture to the factor of the mix color node

I add a color ramp between the grunge texture and the factor of the mix color node

I change the blend mode of the mix color node to subtract

I can use the color stops on the color ramp to control the grunge texture

Texturing (Center)

I copy and paste the shader nodes from the barrel onto the center barrel material

I change the hue and saturation to zero and the value to 3

Texturing (Plugs)

I use CTRL + SHIFT + T to set up the textures for the plugs

I increase the scale of the mapping node

I add a hue-saturation-value node between the base color texture and the principled shader

I change the hue and saturation to 0 and the value to 0.25

I copy and paste the grunge setup from the base material into this material

I adjust the color stops on the color ramp

I add a color ramp between the roughness and the principled shader

I move the white color stop to make the metal rougher

Texturing (Warning)

I select the barrel center material and add a diffuse shader node

I drag-and-drop the decal into the shader editor and connect it to the diffuse shader node

I drag-and-drop the decal normal into the shader editor

I change the color space to non-color and connect it to the normal of the diffuse shader

I add a mix shader between the principled shader and the material output node

I connect the diffuse shader to the bottom input of the mix shader

I select the decal texture node and go into edit mode

In the data tab, I open the UV maps panel

I add a new UV map and rename it

I select the faces where I want the decal to appear

I then unwrap the selected faces

I select the UV islands and move them off to the side

I use CTRL + I to select the rest of the barrel

I select the islands and move them to the side

I reselect the faces where I want the decal

I move them back onto the UV map and scale them accordingly – overlapping the front and back faces

In the shader editor, I add a UV map node and open the default UV map

I add a mix color node between the mapping nodes and the texture nodes

I connect the UV map node to the mix color node

I add a second UV map node and open the decal UV map

I connect the UV map node to the decal texture node

I change the bounds of the decal texture to clip