East West Manufacturing Blog

How Much Resolution Do I Need For My 3D-Printed Prototype?

Written by Patty Rasmussen | March 31, 2017

For obvious reasons, 3D printing is a popular prototyping method — whether SLA, SLS or FDM. But did you know a simple tweak in the software settings can save you time and money when creating your 3D-printed prototype?

Before we get to the setting, let’s do a quick review of how 3D printing works.

The answer to any question about 3D printing almost always goes back to intention. In other words, what is the purpose of the part? Are you just checking out the design or are you going to do testing? Higher resolution has its benefits — the part looks more finished, the layers are less obvious — but it also has its drawbacks. It will take longer to print, for example, and it could be more expensive.

3D printers move quickly from point A to point B, but they aren’t as fast when changing directions. The more points you have on a part design, the more direction changes the printer makes. That slows it down. So the question becomes, how many points does your design have? If you’re making a square it’s pretty simple — there are four points with straight lines between each one. But what if you’re making a circle? Connecting those points will take more and more direction changes.

You can make a circle that looks sort of round, but it will look rough and you will probably see the triangular faces — the faceted edges — making up all the points. But if you bump up the resolution in the software, if you put more points in the design software telling the printer what to do, it will slow down the process. They don’t always look terribly different, but up close you can see the difference, and the time it takes is significantly different.

High resolution takes longer, but it’s much closer to what you’re actually making. It’s closer to the design intent.

Image courtesy of SolidWorks

Now let’s get to that setting. 3D printing uses something called standard tessellation/triangulation language or STL files. It’s a format using a series of triangles to portray the surface of a 3D model. STL files are considered the industry standard; the format that can be understood or read by most 3D printers.

All printers come with default settings, coarse and fine. They also come with a custom option. To have more control over resolution variables, to print the model you actually need, choose the custom option. We talked with one of our engineers about this issue of resolution and he told us that the only way to get to true design intent is by playing with the resolution, but it will affect run time.

“If engineers here send me a part to print, usually with an STL, they’ll send the default resolution,” he said. “They might not know that if they needed it faster, if they dial the resolution down, they could print it an hour faster. Or they might say, it just doesn’t look right. If they have the time to spare, they can push the resolution up and see how accurate you can get.”

Our engineer suggests taking the extra step of playing with the resolution to best suit your intent. It’s a simple, low-cost way to possibly save time and money in the prototyping process. Who knows? It could even help you develop a better part.

Check out these posts for more information about 3D printing and prototyping:

How to Determine the Best Prototyping Method? 5 Questions to Ask

How Small Design Changes Can Affect Product Development Pricing