Designing packaging with no need for glue or staples
posted this on July 20, 2011, 15:38
Many designers have dabbled in packaging. For some it’s a matter of interest, but for others it’s more of a necessity of figuring out how the product they designed will be packaged. Sometimes aesthetics are the main consideration, but a level of functionality is imperative in all packaging. What if your product needs to be shipped? You need packaging that is robust. So if you’re making a product with Ponoko, why not use the same service to create custom packaging for your design? In the future, the Magic Box app will hopefully do all the hard work for you, but for now there’s some serious 2D->3D thinking involved. If you’re using parametric modelling software, it’s as easy as using the sheet function and exporting the resulting technical drawing as a vector file. However, if you’re drawing your design in a vector program, there is a lot to consider.
Firstly, these designs are hardly scalable. You cannot simply drag a corner of the bounding box to change the template size and expect the result to work. This is because the wall thickness has to remain constant whatever the box dimensions, and that affects eeeeverything. There is the option of having scored fold lines on the inside of the package or the outside. Inside is more functional because that conceals the raw edges that catch on things and wear out, weakening the result. When designing the template, you have to take into account how the wall thickness determines the position of the score lines. As you can see from the diagram below, when the cardboard is bent, the wall ends up on the inside of the red score line, reducing the inside perimeter.
Let’s say, I’m packaging a square jar. The jar is full of tasty jam and is going in my long haul luggage. I’d rather not open the bag at the other end to find sharp shards of sticky glass and jam smeared over everything inside. I’m going to make a box that will protect the jar. So why not bubble wrap? Bubble wrap will take up more space to offer the same level of protection, and it is not befitting of a gift. I want to create a design that uses tabs and slots to keep everything together – no need for glue, tape or staples.
The first step, of course, was to measure the jar. The box footprint is that of the jar with two layers of cardboard around it, so if the jar is 60mm square, and I’m using 6mm card, the final footprint of the box will be 104mm square.
When designing the template, the rule of thumb is to add the wall thickness measurement to either side of the score line. The space in between the grey rectangles (excluding the tabs) adds up to the inner perimeter of that layer.
At small scale, the tolerances are not particularly forgiving, and my big pile of prototypes is sound proof of that. You can use the basic guide above to design your own box. A P3 will allow you to make a cube up to 120mm in internal size. Of course, you can skip all that work and download the free file for the small box here. The file comes with scaling instructions. You can also download a free file for a bigger box of 130mm (external).