Introduction: Custom Mount for Garmin Nuvi GPS
If you have ever been in a Volkswagen New Beetle you might have noticed that the dash is deep enough to take a nap on. This makes the suction cup mount provided with the Nuvi pretty much useless. You would have to press your chest to the steering wheel to touch the device.
So out of necessity and the desire for a more finished look I created a custom mount that uses the bud vase as the attachment point. If you are unfamiliar with the VW bud vase it's important to note that it's not just a little cup in a hole. There are actually three pin on the side of the vase that lock it in place with a twist. This makes for a very secure attachment point.
Step 1: Construction Overview
- ~16" of 3/8" soft copper tubing
- 17mm ball, hard plastic or metal
- 1/2" long 3/8" diameter brass or copper rod
- Solder and pipe flux
- Black spray paint
- Masking tape
- M3x10 socket head cap screw
- Propane torch
- Hack saw
- Belt or disc sander
- Metal lathe
- M3 tap and drill
Step 2: Ball Joint Construction
Now we need to get all the parts made for the mount. The Nuvi attachment plate attaches to the suction cup mount with a ball and socket joint. The ball potion of this is 17mm in diameter and plastic. In order for this to work you will need to purchase or make a new ball. Having access to a FDM rapid prototype machine I chose to simply model the ball in ABS. It fit as modeled but the rough surface finish made for a notchy adjustment feel. So I modeled another ball 0.5mm over-sized and lightly sanded the outside to smooth out the ridges. This sanded version fit and felt exactly like the factory ball. The ball has a clearance hole for an M3 socket head cap screw and a counter bore on one side for the screw head. The other side of the ball has a 3/8" counter bore to fit over a turned brass plug. This plug is tapped for M3 and the back side is reduced to fit inside the copper tubing.
If you could find a brass, copper or bronze ball in the correct size you could skip the whole plug and screw thing and solder the ball directly to the end of the tubing.
Step 3: Soldering
The plug is soldered into a short section of tubing with a 45 degree angle on one end. Clean everything well and use acid based flux. Heat the assembled pieces until you can touch the solder to the metal and it melts. Apply solder to the edge of the joint and it will wick in.
The miter joint is a little more tricky. Make sure the fit of the two pieces is excellent. Rough cut the angle with a saw and then sanded until the angle is right and there were no gaps. It will take a bit of fixturing to support the pieces before you start to solder. Again use flux, heat the joint and let the metal melt the solder.
After everything is cool I would recommend trying to break the joint. You should be able to give it a very good pull just short of where you would expect it to start bending. If it breaks, clean everything and try again. You are going to be hanging a $400-$800 piece of fragile electronics on this joint so you want it to be solid.
Step 4: Bending the Tubing
Now you need to bend the lower section of tubing to place the mount where you want it. This is best done in the car. Work slowly and be very careful when bending the tubing if you try to bend too sharp of a radius it will kink and you'll be soldering on a new lower section. Make sure the Nuvi will be far enough back so you don't hit it as you turn the wheel.
Once you have it bent the way you want it's time to paint. I chose flat black spray paint. You will want to tape off the bottom inch or two of the tubing before painting so you get a good bond joint later on. Also remove the ball and do not paint it. This would only gum up the ball and socket joint.
After the paint is dry head back into the car. Lock the vase in place and get the tubing arm oriented correctly. Now tape the tubing mount to the vase to hold it in position for bonding. Once it's securely taped you can remove the assembly from the car.
Step 5: Gluing the Tubing Into the Vase
Now all that is left is to fill the bottom third of the vase with epoxy to hold everything together. You could fill the vase to the top but then you wouldn't be able to put flowers in it. Cure time will be based on the epoxy you are using. Once fully cured you can remove the tape and try it out in the car.
Step 6: Installing in the Car
This is the finished mount without the flowers. Adding flowers will hide the tubing and the Nuvi will appear to just float above of the flowers.
Step 7: Add Some Flowers and Drive
This is the view from the driver's perspective. The bottom of the Nuvi is just above the wheel rim and the top is still below the bottom of the windscreen. This results in no loss of visibility. It is also in the same plane as the instrument cluster making it easy to look between them.
If you need to move the Nuvi to another car temporarily just pop the back plate off your custom mount and stick it back on the suction cup mount.