MiniCard Holder with 608 Ball Bearing (for "MOO" cards)

thingiverse

This is a nifty card holder for the popular MOO-style MiniCards, inspired by the official MOO MiniCard holder. You can open it, push out a card, and click it closed all with a single hand. Watch the video. It can hold up to twenty "classic" MiniCards (the official card holder holds only twelve), but it can be adjusted to hold more or less by editing the OpenSCAD file. The size of the holder will be adjusted proportionately. A custom message can be added to the lid using customizer or by editing the OpenSCAD file, which is great for gifts. It uses a common 608 skateboard bearing for the hinge, giving it a unique industrial look. There are a variety of different styles and colors of 608 bearings. Instructions Some assembly and finishing is required. Parts The holder requires a 608 ball bearing, commonly used on skateboards, roller skates, roller blades, and RepRaps. 3D printed 608 bearings may also work, but I haven't tried. If you are printing with PLA, you will also need some materials for sanding. At a minimum, you must sand the card ramp in order to smoothly slide out cards. I recommend sanding in three stages (using 60, 150, and 320 grit), using an abrasive-sponge type sanding block: If you are printing in ABS, you could possibly avoid any sanding by using an acetone vapor bath. If you do this, some masking may be required on the bottom of the lid and the top rim of the base to ensure that smoothing doesn't happen in places that should be flush when closed. Printing This thing should be printed with a layer height of no more than 0.1mm. Printing at layer heights larger than 0.1mm is not recommended. Infill can be anything between 20% and 100%, with the higher infill adding a satisfying weight to the box. I have personally printed this object using PLA, but it should work great with ABS, too. I print with a 0.4mm nozzle, 1.6mm walls, and 1.0mm solid layer height. This makes the object very robust. I print without a raft or brim to make cleanup easier. After printing, it is a good idea to sand and smooth the parts and also test to make sure that they are fitting together well. Once you insert the bearing, sanding the top of the lid will become more difficult. Be sure to sand all of the areas where the lid touches the base, including the locking notch. Be sure to remove any burs that might have cropped up in printing. Sanding If you aren't printing in ABS and doing an acetone vapor bath, you will need to—at a minimum—sand the card ramp. Since some sanding is required anyway, you might as well sand the whole thing and make it look extra nice. Start out sanding with the coarse (60) grit. Don't press too hard, let the sanding sponge do the work. Once you have sanded away all of the visible layers, move on to the medium (150) grit and finally the fine (320) grit sponge. After sanding, rub down the parts with a soft cloth to make them shine. Assembly First insert the ball bearing into the lid from the bottom. Carefully push the ball bearing into the lid until it is flush with the surface. You might not be able to do this with your bare hands. I place the bearing and lid between two books and lean on the books to mate the pieces. Other methods (using a vise, for example) would also work. Once the bearing is flush with the top of the lid, arrange the lid at a 90° angle from the bottom and press the bearing into the slot in the bottom. Again, the book trick can be helpful here. Once you have the holder assembled, open and close it a few dozen times to break it in. It should close with a satisfying "click" and open without too much force. If you think the holder is too hard to open, perform some additional sanding on the locking edges of the lid and base. Enjoy your new MiniCard holder!