Magnetic screwdriver handle for 1/4" bits (repairable)

thingiverse

I have tons of 1/4" screwdriver bits and adapters on hand, but sometimes I need a short handle to get the job done efficiently. I've tried some designs online, but they all had major flaws. Some were too small for my hands, while others didn't feel secure in my grip. Then there was the issue of magnetized parts popping out, which made me think it's time to create my own handle with magnets embedded inside that won't come loose. This design is larger than most, measuring 50x30mm, and features two 10x5mm rare earth neodymium magnets: one for holding the bit in place and another at the back for attaching the handle to metal surfaces or catching ferromagnetic screws. The cool thing about this handle is that it can also be used as a fridge magnet! I've designed two models, a fixed one and a repairable one, with the short handle being the latter. If you're interested in more details, check out the "updates" section below. To make this handle, you'll need to get your hands on two 10x5mm rare earth neodymium magnets (you can find them online for a couple bucks) and some basic 3D printing skills. Since the magnets are fragile and prone to oxidation, they're totally enclosed within the handle to protect them. To compensate for the extra distance between the magnets and the metal parts, I've used powerful 10x5mm magnets. Don't even think about using normal support during printing; baseplate support is a must to ensure that you can insert the magnets properly. When working with these strong little magnets, be careful not to pinch your fingers, as they can easily get pinched. This handle is for adults only and should be kept out of reach of children. If you do let them play with it, make sure it's enclosed in the handle first. Printing this handle requires some specific settings: at least 40% infill, 3mm shells, and 0.2mm layers. I recommend using ABS for the best results. If you're a frequent buyer from DX, you can find these magnets on their website under SKU:388437 or SKU:374922. Just be aware that giving direct links might not be the most convenient option. UPDATE (21-MAR-2017): I've redesigned the short handle to make it repairable. Now, the handle features a hexagonal hole for inserting the bit holder part, which has no magnet inside. If this part breaks due to stress, you can simply print a new one and swap it out in minutes. I've also added a hole to ease the extraction process of the damaged part. I designed this repairable feature because I have strong hands, but even with that said, it's still nice to have an interchangeable bit holder that allows for different types of bits without needing to reprint the whole handle and buy more magnets. This design is easy to do and will save you time in the long run. If you're interested, I can provide you with some new bit parts with exact specs. UPDATE (20-MAR-2017): I've added a new model for 10x10x5mm square magnets because I ran out of my stock of cylindrical ones. These new magnets seem to be less powerful, so I shortened the handle by 10mm to reduce its overall weight. The new height is 40mm. UPDATE (17-FEB-2017): I've refined the model for better prints and enhanced tolerances. Now, it works straight off the bed with no post-print work required (unless you need to remove support). I've added some pics of a transparent PLA print, and I might design a shorter model in the future, but this one has enough grip for me.