Magnespring Bag Clip

Magnespring Bag Clip

A simple bag clip with a print-in-place hinge and a magnetic “spring.” The orientation of opposing magnets makes the actuation of the clip feel as if it has a physical spring built in and makes a satisfying “snap” when it closes. There are currently two variations available, wide and narrow.

Note: If you already have a magnet of a similar shape and size (but not exact) you would like to use, provide exact dimensions of your magnet in a comment and I would be happy to adjust the model to fit your magnet.

Required Magnets

Wide:

4x 25.4x6.4x2.5mm (1.0x0.25x0.1 in) rare-earth block magnets (available here) for each clip.

Narrow:

8x 6.4x6.4x2.5mm (0.25x0.25x0.1 in) rare-earth block magnets (available here) for each clip.

Printing Recommendations & Considerations

• 0.2mm layer height with a 0.4mm nozzle.
• 3 perimeters; 6 solid layers, top & bottom.
• The magnets are inserted during the print and are fully enclosed when the model is finished, so a print pause is required at the appropriate layer to allow the magnets to be placed inside the clip.
• The clip is designed with fairly tight clearances, so make sure your printer is well tuned or you might have difficulties. For instance, the print-in-place hinge might fuse together.

Assembly Instructions

Step 1: Mark your magnets so you can visually verify the poles are oriented correctly when you are inserting them into the clip during the print pause. (Marking your magnets is optional, but recommended.)

Step 2: At the print pause, insert the magnets into the pockets in the clip. Be sure to check that the bottom pair of magnets attract each other and the top pair of magnets repel each other (especially if you chose not to mark your magnets!).

Note: An earlier version of the clip is shown in the pictures above and below. The top magnets have since been moved closer to the hinge for better springiness during clip actuation.

Step 3: Press the magnets all the way into their pockets until the tops are flush with the top surface of the print, then resume the print.

Step 4: Remove the completed clip from the print bed and press the top end together, followed by the bottom end, to break the hinge free. Work the hinge back and forth several times to loosen it up so the clip opens and closes smoothly.

Step 5: Close and clip all the things!

Note: For the narrow version, two 6.4x6.4x2.5mm (0.25x0.25x0.1 in) magnets are inserted into each magnet pocket. Be sure to verify the proper orientation of all 8 magnets before resuming the print!

How To Use

Rare-earth magnets are strong, but at this size, they aren't strong enough to hold many layers of a bag together. For this reason, the clip has been designed with a space for the “roll” of the bag so the bottom magnets of the clip can snap together on just two layers of the bag, allowing a secure hold.

For the bags found on a loaf of bread or something similar which is typically twisted closed, use the following technique:

1. Stand the bag up.
2. Twist the bag closed.
3. Fold the portion of the bag above the twist horizontally, making a “T” shape.
4. Roll the “T” to the bottom of the twist and snap the clip on over the center.

Use it to close cereal bags inside of the boxes.

BONUS!

When not in use they can be kept readily available by storing them on your refrigerator and they also double as a note holder!

Don’t have the required magnets? Print one anyway! It won’t be useful as a bag clip without the magnets, but it makes a great fidget toy!