Design for 3D Printing

so you want to 3d Print your part, you will want to think (and design around) some limitations.

In the Pearce shop we have 2 types of 3d Printers, a Markforged x7 and 2 Makerbot Replicator + s

We use Onshape for the Design, for slicing on the Markforged and myMakerbot for slicing on the Makerbot

Part Size

The most obvious limitation with 3d printing is the size of your machine. Our Makerbots and Markforged printers both have a similar bed size of 20in X 17in X 16in. so you will want your part ( in some orientation ) to fit in this size.

Lofts, Holes, and Voids

When 3d Printing you need to remember that you are placing not just a layer but a string of melted plastic to build your part, if you don't have support underneath your sting of plastic it will bend at best or break at worse. you need to think about what orientation you are going to print your part in, and remove ( or at least lessen ) any voids in the up down direction of this orientation.


3d printed parts are notoriously weak*. you can change the infill settings to make them stronger but this will be the weakest part on your robot.

remember with FDM 3D Printing you are building layers of plastic and these parts can pull apart at these layers (delamination) this also means that the part will be stronger in one orientation vs another. when arranging in the slicer think about how your part will be used and what orientation the forces acting on it will be.

Impossible Shapes

    1. No hanging or floating parts.

Advanced Design

Adding Threads

you can add threads for bolts to your 3d printed parts by oversizing and reinforcing your holes and adding metal thread inserts after the print is done

Thread Insert Table

Rapid Design Quick Refrence

Makers Muse tips for better 3d printing holes

    1. Teardrop vertical holes - (link to onshape feature script)
    2. Clamping slots - (link to onshape feature script)
    3. Compliant holes - - (link to onshape feature script)