My state recently passed a law banning the use of handheld devices while driving. I decided to create a phone mount for my BMW i3 that would hold my phone magnetically and allow for easy charging. Since I would be 3d printing the mount, I used strong bar magnets recessed into a pocket of the mount. Used with a phone case that has a metal plate in the back, the magnets hold the phone securely, even with "spirited" driving.
What you'll need:
A 3d printer (or use a printing service, such as Shapeways)
The attached STL file (or on Tinkercad)
BMW Key emblem (eBay)
Phone case with magnetic back (like this one)
Step 1: Print!
I created the STL file based on the great work of seojeff. Key changes that I made include:
- A "pocket" in the back to hold recessed magnets
- A small shelf for the phone to rest on; the shelf has a hole for a charging cable
- An angled hole through the lower portion so the charging cable can come up from behind
- A small recess on the front for a BMW emblem
I printed this one on my Monoprice Maker Select 3d Printer; Once it's printed, use a sharp knife to trim the support structure from the mounting tab and sand the entire mount with 150 grit sandpaper.
If you want to modify it, the file is on Tinkercad.
Step 2: Sand & Paint
After trimming any support structures, sand the entire mount with 150 grit paper, paying close attention to the edges. After priming with a primer that is safe for use with plastics, spray several light coats of black Plastidip. The Plastidip will give it a finish similar to the interior trim and create a non-slip grip for the phone.
After the paint is completely dry, add three of the bar magnets to the pocket in the back of the mount. They should fit snugly, but you may want to secure them with a bit of hot glue.
As a final touch, I used a drop of Loctite Ultragel to secure a small BMW emblem that is meant as a replacement for the one found on the car's remote.
Step 3: Install
The mount simply slips into one of sockets just in front of the cup holder. The combination of a rubberized coating and the three magnets creates a very secure mount - my phone hasn't slipped even in sharp turns. The braided iPhone cable slips easily though the holes and matches the interior nicely.
If you make one of these, post a pic in the comments!