/ 3D Printing

Fixing the outside mirror control knob on my 2008 Nissan Altima

My daughter is about to get her driving permit, and, much like when the adults get a new smartphone and this results in a cascade of phone upgrades as the replaced phones are handed down to the children, my daughter will become the primary driver of my 2008 Nissan Altima and I'll get a new car. (It should be noted that she feels this logic is backwards.)

As such, I've been trying to ensure that every safety issue with the vehicle has been addressed. New breaks, replacement TPMS, etc. But there has been one nagging problem that I was tolerating, but, ultimately, is probably a safety issue.

The darn side view mirror control knob sunk into the armrest.

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See how the knob is almost flush with the control panel? That is wrong -- it is supposed to be sticking up, so you can easily manipulate it. Yes, you can fairly easily pull it up, but I do not want my daughter to have any excuse to not adjust her outside mirrors.

I had previously addressed this issue in a number of ways. It's easy to remove the armrest and the controls (you can literally just pry them off the door). Once accessible, it's easy to see the problem. The original clips that hold the control knob up and in place are very small, and snap off easily.

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So I used everything from duct tape to twist ties to rubber bands. Each of these proved to be partial, and short-lived solutions. Eventually each failed, and the knob receded again -- once, all the way into the armrest. That's an actual safety issue.

A year ago I received my first 3D printer, and I used it to successfully fix things around the house -- a smoke detector, for example, hanging from the ceiling due to a broken mount. Now that I was about to hand off the car, it was time to address this control knob problem once and for all.

As there was enough room to do so, I decided to create a new bracket that would surround the entire control knob housing and the mounting bracket of the arm assembly. Armed with calipers and some patience, I used OpenSCAD to create the bracket.

controlbracket

Yes, it took a couple of tries to get it right. In OpenSCAD, my debugging technique is to subtract from the final model big blocks of area so I can just print one small part of the object. This let me ensure that my measurements were correct and, when not, make the necessary adjustments and test them reasonably quickly. For example, here's the model with just the side posts:

sideposts

Quick model changes like that are super fast and easy in OpenSCAD -- just use the difference() Boolean operator, and subtract from your model a cube() (or whatever works best to "erase" the unwanted bits).

The final result fit snuggly around the remote control module, and even with PLA feels both strong and flexible (printed with 0% infill). I suspect this will last for many years -- and when it fails, I'll just print a new one.

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I hope my daughter enjoys driving the Altima, and while she may never truly appreciate the subtlety of a fully engaged outside mirror remote control, I'll rest a bit easier knowing she just that much safer on the roads.

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Source available on GitHub.

Thing available on Thingaverse.