Spring-loaded latching mechanism

myminifactory

This is a versatile spring-loaded latching mechanism designed for a wide range of applications. It draws inspiration from the slam latch commonly found in normal doors and some car doors. However, unlike its traditional counterpart, this mechanism cannot be activated by slamming it together. Instead, users must press the pins to release the connection and secure it. To use this mechanism, attach the cage (complete with pins and spring) on one side and the anchor on the other side (for example, a box and its lid). At 100% scale, the screw holes are perfectly sized for M3 screws. By pressing the two pins deeper into the cage, you load the spring and open the connection. Conversely, by releasing the pins, the mechanism closes, and the spring unloads. The force exerted by the spring is sufficient to keep the components securely in place. I have no data on the lifespan of the spring, but it appears to be holding up remarkably well so far. It's essential to remember that slamming the parts together will not establish a connection. Instead, you must push the pins into position. Printing this mechanism requires some care. I printed it at 100% and 66,66% scale (as shown in the photos). At 100% scale, the wall thickness is robustly two to three millimeters thick. Printing the anchor, pins, and cage is straightforward, requiring no special attention. However, printing the spring can be a bit challenging. To print the spring successfully, you must increase the wall thickness in your slicer to more than three millimeters. It's also essential to print slowly for optimal results. You should print all parts with either 0.1 or 0.15 mm layer height, depending on whether you're scaling down the spring or not. To ensure that the mechanism functions perfectly, make sure to remove any remaining brim and first-layer squish from your prints. When printing the spring, slowly compress it to its minimal form several times before assembling it. If the spring breaks during this process, you may need to tweak your print settings. If it holds together, you can proceed with assembly. This mechanism offers several benefits: - It's fully 3D-printed. - It allows for multi-color assemblies. - Printing is relatively easy. - No support or printbed adhesion is necessary (in most cases). However, there are also some drawbacks to consider: - The applicable force depends on the scale of the print. - There's a risk that components may not age or wear well over time. Another latch design that might be more robust can be found at https://www.myminifactory.com/object/3d-print-sturdy-print-in-place-draw-latch-104746. This mechanism was designed using FreeCAD and quickly rendered with CADRays.