Designing a 3D Printable Flashlight Body in Blender

In this Instructable, I will be teaching you how to work with Blender to create a 3D flashlight body. If you have no experience with Blender, I will be teaching some Blender basics along the way. I also recommend a few tutorials if you want to go more in depth and enhance your skills.

Here are some good blender tutorials for those just starting out:

https://www.blender.org/support/tutorials/

https://cgcookie.com/flow/introduction-to-blender/

http://www.blenderguru.com/tutorials/

If you're experienced with 3D design in Blender for 3D printing, feel free to use this Instructable as a guideline for you to help you create your own flashlight body to be 3D printed.

The photos above show several drafts of mine as I tweaked and improved the design. My goal was to use open source technology to create an ergonomic flashlight body that would fit in one's hand well.

Also, I would love to expand this Instructable by 3D printing this for myself. Please vote for me in the 3D printing contest to help make this happen, or if you just like this Instructable. Thanks!

Step 1: Getting Blender

The first step is to download Blender. You can find the right download for your computer here:

https://www.blender.org/download/

When you first open Blender, it can be a little intimidating, but don't fret. You'll be up and running in no time. First of all, your screen may look slightly different than my photos above, as I have customized my startup screen. Yours may not have some of the windows mine does, and in your current view you should have a cube displayed in the center. This object is there as default for when you open a new project in Blender, but we won't be using it for this project.

Step 2: Adding a Cylinder

In order to create a flashlight, you need a basic cylinder first. If you still have a cube in your screen, here's how you can delete it:

1. Type 'A' to select all objects. If you press it more than once you will see it toggle between selected and unselected. If the cube is outlined in orange, it is selected.

2. Type 'X' for delete, and click on 'Delete' to confirm this action.

Now you must create a cylinder. Type 'Shift+A' to add an object, and a list will pop up. feel free to scroll through the types of objects, but the one we want is under 'Mesh'

Hover your mouse over 'Mesh' to see your options. You'll see that 'Cube' is there as well, should you accidentally delete the starting cube and need to use one. Click on 'Cylinder'

Step 3: Other Materials

Before continuing, I recommend gathering just a few other materials to help you create your flashlight.

First, a physical flashlight to help you judge size and shape for your printed one. Second, I highly recommend a ruler. It will help you scale your flashlight to correct dimensions.

Step 4: Rotating the Cylinder

Looking at the current screen, the cylinder probably doesn't look much like flashlight material. Right now, you need to rotate it and then it before continuing. Here's how you can do that.

Rotating:

1. Select the cylinder. You can do this either by clicking on it with your mouse, or by typing 'A' to select all objects, which is just the cylinder right now.

2. Type 'R' to rotate the object. If you move your mouse around, you should see the cylinder spin around with your mouse movements.

3. Type either 'X' or 'Y' to confine the rotation along either of those axes. It doesn't really matter which, and you don't really need to rotate the cylinder at all, but I find it easier to work with a horizontal flashlight, so we want the "ends" of the cylinder to be across from each other horizontally.

4. Type '90' and then hit enter. You should see the cylinder rotate horizontally. this will make it easier to edit, from a visual standpoint.

Step 5: Scaling the Cylinder

Scaling:

Look over at the data window to the right of your view window. If the cylinder is selected, you should see a section under 'Transform' marked 'Dimensions' as in the photos above. Changing these numbers will alter the length, width, and height of the cylinder, corresponding to the labelled axes. Change them to fit your fancy.

This is where having the physical flashlight and ruler comes along, as you can measure it out and get a rough idea of how large you want your flashlight to be. I measured mine in millimeters, so this is the unit I will use in Blender. Most 3D printing applications let you choose before you print, so make sure you know which unit you are using here, or your print may turn out too large or too small.

My dummy flashlight was 25mm by 25mm by 90mm, so I used these dimensions in Blender. If you want different dimensions for your flashlight, you can change these values to scale your flashlight.

Step 6: Beginning to Edit the Flashlight

Now, if you printed your flashlight as it is now, you would print a solid cylinder. Not only would this be a waste of printing time and plastic, it would not make a very good flashlight body. So, we need you edit our flashlight, to hollow it out and alter its shape. to do this, first you need to be in edit mode. You can press the Tab key to do this, or go down below the view to where it says 'Object Mode' and click on that. A drop-down menu will give you some options, and you can click 'Edit Mode'

Now, you should see individual points appear on the cylinder. In order to make selecting these points easier, you must do two things.

First, go into Orthographic view mode. You can do this by either pressing '5' on the number pad, or by clicking 'View' and then clicking on 'View Persp/Ortho' which will do the same.

Doing either of those again will toggle back into Perspective mode, which makes it easier to visualize the object in real life but harder to select parts of the object in Edit Mode. Both are necessary to use in Blender, as they each have their purposes. If, at any time, you are unsure of which of these modes you are in, you can see for sure at the top left of the view window, where Blender will tell you.

Finally, if you look underneath the 'View Persp/Ortho' option in the 'View' menu, or if you experiment with other numbers on the number pad, you'll find you can change the view to a specific angle.

Change the view angle so that you can see the cylinder as a horizontal rectangle. This is either 'Left' or 'Right' on mine, but it depends on which axis you rotated the cylinder down by earlier, X or Y.

Step 7: Shaping the Flashlight

Press 'Z' to toggle between wireframe and solid view. In solid view, selecting parts of an object only selects what you can see, but in wireframe, you can see all of the object.

Now, select all of the object by pressing 'A' if it is not already selected. We are going to create more points along the length of the flashlight that you can shape your flashlight by.

Type 'W' and then click 'Subdivide'

Type in the number of subdivisions you want and hit enter, or go to the Operators window to the left of your view, and change the number there. You'll only need about 5-8 subdivisions along the length of the cylinder.

Now, you can shape out the flashlight body. To do this, unselect all points, and then type 'B' to "Box select" some points. Now, you can draw a box to select a number of points. After selecting the points you want to shape, press 'S' to scale these points, and move your mouse to scale the objects to fit your taste.

Now you can shape the flashlight to make it more ergonomic.

Step 8: Hollowing Out the Flashlight

Once you've shaped the outside of your flashlight body to suit your likes, it's time to shape the inside. This means hollowing the body out to contain the electronics and batteries necessary to being a flashlight.

First, you need to delete the end faces of the body. I recommend doing this in Perspective mode so you can easily rotate around the flashlight and see what you are doing, so change into Perspective mode now.

Now, down below the view window, you should see three boxes just to the right of the menu labelled "Global"

Click on the rightmost box to make sure you can select faces. When you look at the view window, you should no longer see dots on the vertices of your cylinder, you should see them on the faces.

Now you need to rotate around the flashlight and select both end faces. You can do this by selecting one, by clicking on it, and then rotating around and clicking on the other one while you press 'Shift'

Press 'X' and delete the two faces, making sure to select "Faces"

Now, get back into Orthographic mode, and go to the "Right" view, or whichever one you used earlier.

'B' select the endpoints on one side of the body. Make sure you are in wireframe view so you select all the endpoints, and not just half of them.

Now, you will learn a new skill. Type 'E' which stands for "Extend." If you move the mouse around, you will see a second ring of endpoints attached to the first one move around with your cursor. This is what the "Extend" function does. Right now, you want to keep the new ring in the same place, so extend the ring and then hit enter without moving it.

The new ring should be selected now, even if you can't tell. Type 'S' to scale it, and then scale it in, making sure it is than the smallest point on your flashlight body. Once you've scaled it to a good size, hit enter.

Extend the ring again, and now type either 'X' or 'Y' to constrain the extension to move only along that axis. Which one you do depends on which way horizontally your flashlight is lying. Make sure you constrained it the right way, and then pull the extension all the way through to the other end of the flashlight, and then type enter.

Step 9: Sealing Off the Gap

To make your flashlight body solid and printable again, all you have to do is seal off the end. Do this in Solid Perspective view. Make sure you can select edges, instead of faces or vertices.

Zoom in close on the end that is open, as in the photos above. Select two edges opposite each other, and then type 'F' to join them with a face.

Go around the circle, doing this for each face, until you get back to where you started. Now your body is solid again.

Step 10: Going Further

Your flashlight body is ready to print now!

However, if you want to elaborate your plans for a more impressive flashlight, there are a couple of things you can do.

Step 11: Going Further: Adding a Cone

You can add a cone to the inside of your flashlight with the skills you already have.

First, I hid the outside of the body by selecting the inside and pressing 'Shift+H' You can undo this and reshow all hidden parts by pressing 'Alt+H' when you need to. Right now, it just makes it easier to work with the inside of the flashlight.

Now you can create a cone on the inside to direct the light of the bulb or LED. I subdivided the length of the inside cylinder twice, and then moved the subdivisions close together towards the front of the flashlight. Then I selected the vertices on the subdivision that are farther forward, and scaled these down very small, creating a cone.

Step 12: Going Further: Adding Grooves or Ridges for Sleekness and Ergonomics

Adding grooves or bumps lengthwise (or around) your flashlight can add a sleek look to it, while also adding to the ergonomics.

To do this, select lengthwise lines of faces around the flashlight body all at once, as in the photos. Scale these up or down to fit your liking.

I scaled them up, and then rescaled the back ends down to have the outward ridges curve down into soft grooves toward the back of the flashlight.

Step 13: Final Notes

Now you can 3D design, print, and build your own flashlight!

Above are some photos of the final model created in this tutorial next to my dummy measuring flashlight for a size comparison, as well as some other drafts of mine. I added ridges around the flashlight to fit in one's hand better, and on the final draft, I separated the cone and back into their own parts, which screw on, and smoothed out the design using a subdivision modifier to be more sleek.

If you have any suggestions or comments, or if you would like to share your results, please do so in the comments below, and Happy Inventing!