Finished Card

Think you need to be able to use 3D CAD software to produce your own 3D models? With the award-winning open-source Cura slicing software by Ultimaker then think again. The software can make 3D models from good old 2D .JPEG or .BMP files.

This is one of the easiest ways to start 3D designing. All you need to do is be able to think in terms of black and white (and the shades of grey in between).

The way it works is to build your 2D image up from the build plate, you just need to tell it how high you want it to print when you load your JPEG into Cura.

It then takes the information in the file and prints to that height where it’s black. If it’s white then it doesn’t print at all. And if it’s a shade of grey in between then the height to which it prints depends on how dark it is. Darker grey areas print higher than lighter grey areas.

To illustrate the technique take the following JPEG file that I created to make a 3D business card. There are only three shades in this example, black, white and a grey (which forms the main body of the card) that is 50% black, i.e. half way between black and white.

Steves Educating Card2

I loaded this image into Cura and when the pop-up box “Convert image..” appears I applied a Height of 2mm and Base of 0mm. The width was set at 85mm so that it makes a credit card size print.

Convert Image

The result in Cura looks like this, the black areas of the Ultibot, the “Imagine It Make It” text and my details all print at 2mm high. The Ultimaker logo appears as a hole (zero build height), and the background is 1mm high as it’s 50% black and is therefore half of the specified build height.

The finished card is shown here printed in white PLA. The raised areas have then been coloured (in this case with Sharpie marker pens, though you could also use paint), and then a spray of lacquer has been applied to seal the print.

Finished Card

This is a really versatile way of 3D modelling where you don’t need any complicated vertical shapes.

Give it a go with any JPEG, it’s fun to see what Cura produces. If you import a colour picture rather than a greyscale one it will still work as it automatically converts the colours to the equivalent shade of grey.

Cura can also reverse the process where white is the build height specified(if that is more appropriate for your image), just change the option at the bottom of the “Convert image..” box.

Have fun experimenting. Using this method it’s definitely a case of Imagine It (In 2D), Make It (In 3D) !!

Steve Cox – Education Ambassador
CREATE Education Project

Follow Steve on Twitter: @SteveCox3D or contact directly at

In The Classroom

This tutorial demonstrates a really good technique for introducing 3D Printing to younger students who are yet to learn or master 3D CAD software. There are many simple 3D Print projects you could undertake using this method particularly for infants and lower primary students. Ideas include personalised bookmarks, door name plates and coasters. Students can freehand draw their designs using pencils or marker pens, then these can be photographed to produce a JPEG. Alternatively students can use simple 2D drawing software to create their designs and save as a JPEG. You may wish to create template outlines for the students to create their designs inside in order to standardise and constrain the print sizes, then multiple JPGs can be arranged on the print bed in order to print multiple pieces of work in each print run and save time in starting new prints.

Leave a Review: