The dream of translating your design vision into a pattern that fits perfectly (without having to sell the farm) is now a step closer with ExactFlat Online, available in the Onshape App Store.

Businesses and hobbyists who need patterns in order to build products know that translating real world, 3D objects into 2D production materials is tricky at best, and near impossible at worst – especially when done by hand. Flattening is a long, tedious process made tougher by the fact that an improper fit in the final stages often means starting from scratch. Automated solutions are available, but are often overly specialized to one industry and start at $50,000. This is not exactly feasible for smaller businesses with a smaller production volume.

ExactFlat and Onshape share the same mantra: Design and production solutions should be easy to use, and should work with the tools that you have already invested in (i.e. cutters, scanners, etc.).

To better illustrate this point, let’s take a look at a hot air balloon made in Onshape. We’ll be working through an ExactFlat workflow from start to finish, and you’ll see for yourself how ExactFlat and Onshape make a tricky process simple. Feel free to whip out that high tech backpack or composite bicycle design you've been working on, and follow along.

Rapid Pattern Perfect

The ExactFlat Plugin, which can be downloaded here, makes jumping into the ExactFlat workspace from Onshape as simple as selecting the faces we’d like to flatten. By selecting multiple faces at a time, we can define that face grouping as one piece. Thinking of the lines where different pieces meet as seams, just like you would on the completed product, will help you preserve your design intentions through the rest of the process.

Before we can get to the good stuff, we need to do some cleaning up. The untouched mesh imported into ExactFlat is an early indication of any problems that might have been created while designing our model. There are some options for adjusting the workspace parameters and display graphics, but what we’re interested in now is the Remesher tool. ExactFlat’s Remesher will arrange and reduce the vectors for more efficient flattening. The only decision we need to make here is if the quality of the remesh needs to be increased to capture the complexity of our part.

The new mesh looks pretty good, so we’re all set to move on to the next step. We select our pieces and head over to the Flatten Tab.

The Flatten Tab is where the magic happens. Our pieces are separated and arranged on the right screen, but they aren’t flat yet. To get them into an approximate 2D shape, we’ll need to use one of our Pre-Flatteners.

Our Pre-Flatteners all do the same thing, but are each intended to handle any kind of geometry. ExactFlat Online was created to produce high quality patterns quickly and easily. Regardless if you intend to sew, weld, or glue your product together, Exactflat works for any material.

Our other goal with the Pre-Flatteners is to get rid of any overlap in the mesh, called flipped triangles, which we have helpfully indicated with bright lavender squares.

Flipped Triangles

Because the hot air balloon we are working with has curved geometry, we will be using the Pelt Pre-Flattener.

By now, your sharp eyes will have no doubt noticed the colors that appear on our mesh in this tab. This indicates strain, places where there is too much or too little material, and we’ll be reducing all or most of it with the Optimizer. This tool will get our pieces adjusted into the final pattern. We select our pieces, and then select the material – or the material nearest to ours in pliability and stretch – and the Optimizer does the rest.

From 3D Model to 2D Pattern in 10 minutes or less

And voila! We now have a clean optimized pattern generated from a 3D Model in Onshape, with no elbow grease or prayer needed. We need only to hop over to the Finish Tab to double check our parameters and seam allowances before downloading our pattern in PDF or DXF form.

Do it yourself

If you’d like a more in-depth look at our process, take a look at ExactFlat’s Help Video series or please contact me at We’d love to hear about the projects you are working on, and how we can help. Once you’ve practiced with ExactFlat a few times, you’ll be able to create patterns in less time than it took you to read this article. Thanks for reading, and happy flattening!