How to Design a 3D-Printable Box

I got myself a 3D-Printer a year ago and started thinking about printing some small boxes for a resistor sortiment. But unfortunately I couldn't find anything that would fit my needs and is also printable on my 3D-Printer. So I started experimenting to draw boxes in Fusion360.

After some time I came to a design, I thougt was pretty good.

In this Instructable I will try to show you how to design boxes for your needs, with the help of my own creation.

You will need basic knowledge of drawing, extruding, copying and moving objects in CAD. There will be another Instructable where I show the process for CAD beginners with an easier to use CAD program

A link to my final design can be found on Thingiverse:

https://www.thingiverse.com/thing:2377114

First you need to choose a software in which you will design your box.

There are many professional programs like AutoCAD, Fusion360, BricsCAD, and so on. If you have access to one of these and already know how to work with CAD programs, I recommend going with one of these.

If you are a beginner, or don't have access to the programs named above, I can recommend https://www.tinkercad.com/ which is an online CAD program, where you can learn to design small things. With some time you are also able to create much more complexe designs.

Next you should also decide if you want to use your design as a guide for a build out of would, for lasercutting or for 3D-Printing. With each method you have to think about different aspects of designing. I will go into detail with 3D-Printing.

Now with the CAD-software of your choice start to draw a basic shape of you box. Maybe make some sketches on a piece of paper.

I decided to make my boxes to be able to connect with each other, so I looked into some designs online to find out how other people made the connection of such boxes.

I then drew the shape I had in mind, as seen in the first picture of this step. Make sure to let a small gap everywhere you want to have two parts connecting, or move freely. This is because 3D-Printers are not perfect, and have tolerances in wall thickness. The better your printer is, the lesser tolerance you have to give it. A cheap printer will need about 1-2mm of distance between two parts.

Also add into your design the inside area of your box that should stay empty.

Then extrude the walls of your box to the desired height as seen in picture three. Now extrude the previously created drawing of the area, that should stay free, with the desired ground thickness.

Now you have your basic box design.

As in my design you may need a drawer, to make the look of it better.

This is a lot trickier than the box. I recommend starting of with the area you draw before to let free in your box. Draw the same again, and draw the wanted bottom and side walls. See an example in the first picture.

Now extrude these walls to the height of the box minus the thickness of the ground plate of the box. For example for a box with the height of 15mm and a ground plate with a thickness of 2mm you will extrude the walls 13mm long.

Now extrude the drawing of area you started with at one side of the already extruded drawerpart. For the looks I recommend the same height as your walls are thick. This will be the backside of your drawer.

Now you need to move the whole drawer down or back, so that the front side of the drawer is flush with the drawing plane.

Start drawing a good looking front part, since this will be the part, that is always visible. Extrude this part back into the drawer and have the final form of your drawer. You can always draw something special afterwards and add it to it as I did with a handle.

First of all the drawer will not fit, if you don't use a high end extremely expensive 3D-Printer. So you will have to shrink its size. Most CAD programs offer a function to scale an object. For myself shrinking it to 0.95 or 0.9 times the original size worked out, but you may have to experiment with it yourself, since not every 3D-Printer is equal.

After printing some small test parts I came to the conclusion, that my design was good, but not perfect. It used a lot of plastic and had to much clearance between the parts. So I designed my box with thinner walls, and a small change in the connection of the boxes.

I let the inner free part the same, since I didn't want to redesign the drawer, but added more connecting parts on the outside of the box.