Custom Phone/GPS Car Mount Adapter

This instructable will show you an inexpensive way to make a custom phone/GPS mount for your car without glue or screws.

I was looking for a way to mount my iPhone in my car in a position that allowed me to easily see the screen without having to look away from the road too much and operate the phone with out letting go of the steering wheel. I didn't want anything that would damage the interior with adhesives or screws. When shopping for car mounts I found suction cup style windshield mounts, which were very cheep but California law prohibits what you can attach to your windshield. Vent clip attachments would not place the phone where I wanted it and, of course, would block a vent. Custom molding mounts were too expensive and would have to be replaced if I ever changed cars.

A friend of mine came up with a pretty good solution by sticking an inexpensive suction cup type phone mount to the glass in front of her instrument panel. I found a suction cup windshield mount holder for a couple bucks online. I ordered two, one for my car and one for my wife's. Unfortunately the glass on my wife's instrument panel is curved so the suction cup couldn't get a seal and the only place it fit on my car covered the odometer and tended to fall off every now and then.

My solution was to make an adapter that would securely attach the car mount holder to the dashboard.

Materials needed:
- Thin sheet of aluminum or tin. It should be strong enough to hold its shape but thin enough to wedge between the molding pieces on your car's dashboard. (I found some at an art supply store with the model making stuff for less than $5. I'm sure you could find something similar at a hobby shop or hardware store. You could probably salvage a suitable piece of flexible smooth metal from a tin container or some other product.)
- Cheap suction cup style windshield car mount holder for your phone or device.

Tools needed:
- Tin snips or super strong scissors (anything that can cut a thin sheet of semi-soft metal)
- Pliers

Optional items:
- Thin cardboard
- Pencil, Sharpie(marker), and/or some other mark making implement
- Spray paint
- Painter's/Masking tape
- Bench vice
- Scrap wood
- Sand paper or grinding wheel

In order to attach your suction cup style holder to your dash you will need to create an adapter. It should have a flat surface in on its face and tabs in the back that will wedge into the seams in the dashboard.

Find a flat spot on your dash where two molding pieces meet. You will wedge the tabs on the back of your adapter into the small gap between the molding pieces.

I chose the spot under the top edge of the dash and above the air vent. This will put the holder within reach of the steering wheel and easily viewable while driving.

Use a thin piece of cardboard (or thick paper) to make the basic shape you will need for your adapter. It should be at least as wide as the suction cup base on your holder and longer than you think you will need.

Slide each end of the cardboard into one of the gaps between the molding until it stops. Mark the depth with a pencil.

Then trace the suction cup at the base of the holder onto the middle of the cardboard.

Trim off the ends you marked. Place them on either side of the circle you traced in the middle of the cardboard. You can use them to judge how much space you will need for your tabs.

Fold the cardboard to make tabs that will wedge into the gaps in the molding. Be sure to leave a flat area for the base of your holder. Pay special attention to the angles and curves of the molding.

Trace the shape of your template onto your metal sheet. Be sure to mark all of the fold lines.

Also trace the shape of the suction cup at the base of the phone holder.

Divide the square around the suction cup trace line into thirds. Connect the dots to make four triangles at the corners around the circle. These will form tabs that fold over and hold the base in place.

Be sure note which lines you will cut and which ones you will fold.

Trim off excess metal from around your design and cut along the cut lines to form triangular tabs on center panel. I used my super shears, but tin snips or a proper metal cutting tool would probably be better. In a pinch I have cut through this type of metal sheet by repeatedly scoring with a steel cutting blade (razor blade), or even bending back and forth until it breaks. I really recommended a proper metal cutting tool. Be careful of sharp edges. 

If you use an improper tool to cut your template (like I did) you may have warped the metal in the process. Flatten it between two pieces of scrap wood or anything flat and heavy.

Match the bends in your metal to the folds in your cardboard template.

Use the straight edge of a table or scrap wood to make your bends.

For small areas that are hard to hold with your fingers a table vice is handy. If you don't have that pair of flat nosed pliers works pretty well too.

Bend up your triangular tabs about 90 degrees. leave room to attach the holder base. You will fold them over the rest of the way later.

Now it's time to test the fit. Try wedging the mounting tabs into the gaps in the molding at the spot you chose on the dash. You may need to make some minor tweaks to the bends or trim off some metal to make the adapter fit perfectly.

If you don't like the shiny metal look, you may want to choose some paint to match your phone holder or dash color. I had some flat black spray paint around, so I used that.

Note: You may want to paint the adapter after you have the suction cup in place and use a glossy paint rather than flat. I found that the suction cup did not want to seal over the mat paint. I also found the paint can crack or chip when you are bending the triangular tabs into place.

You will see in a later step that I had to add some adhesive to get a good seal and touch up the chipped paint in some areas.

Center the suction cup base of your holder between the triangular tabs. Bend the tabs over the top of the holder base. Pinch them down tight to get a secure hold. If you left raw metal under the suction cup unpainted it should be able to get a decent seal. The triangular tabs will keep the suction cup from lifting away from the flat surface and loosing it's seal. If you wanted to get really hard-core you could bend down the tips of the triangles and pierce them into plastic on top of the base.

Note: Because I painted the metal before I attached the base, I had to add some silicone adhesive to the suction cup to get a better seal. I used silicone sealer because it is easy to remove from plastic if I ever want to remove the adapter.
You can see in the photo how the paint chipped where I bent the tabs over. I had to touch up the edges with more spray paint.

That's pretty much it! The only thing left is to fit the holder and position the phone/GPS where you like it. I like to have mine right near my line of sight without blocking the windshield and close enough to my steering wheel that I can easily operate it without letting go of the wheel.

I used this same basic design to make an adapter for my wife's car. A vent mount design works better for her car. So instead of fitting tabs into the gaps in the molding I cut out two arms that fit into the vent and hook behind the grate. It hangs securely from the two hooked "arms" without any support on the bottom.