Down the Mirror Mount Rabbit Hole We Go...

[Origin7]

I intended to spend a few minutes during lunch figuring out a way to mount side mirrors to my car. What transpired was an unexpected journey down the mirror mount rabbit hole. I don't know why I've spent hours upon hours on this, but here we are. 

 

First, I needed a good mirror. The SPA mirrors look great, but the mount has a relatively large 2-bolt flange. I didn't want to have to design a mount around the geometry of this flange. I think DPR sells a single-bolt mount, but it's quite costly. Eventually, I came across Life Line mirrors. The FIA Formula in the MSA shape is perfect, single bolt mounting and and it's only $47...done.   

 

Next comes the mount design. I fired up the 3D printer and started iterating...over and over and over. I'll never admit how many of these things I actually printed. But, I eventually ended up with 2 versions, which I then iterated upon independently. Here are a handful of the "winners":

 

 

 

There are several versions of the "Eccles", 2-beam design out there, including the machined ones that DPR sells. I like this design especially for FDM 3D printing. This is also a good design for production because there is minimal material removal/lower cost. However, I like to be different. I plan on cnc'ing these out of 7075, so this allows me to remove more material. I also tend to like very subtle, simple designs with minimal features. So, I am settling in on this: 

 

   

 

I think this works well with the car. It captures the square lines, with filleted corners that you see in the Caterham body.  I'll test a 3D-printed version and put out the file if anyone else wants to use it. It will be the same basic design but with some areas slightly beefed up due to inherent weakness in 3D printed parts. 

 

 

[Origin7]

I added a 2nd point of contact to stiffen everything up in that corner of the door and reduce vibration. Here is the end product. 

 

 

 

If you want to print a set of your own, here is a STEP file. It is the left side. Just mirror it in the 3D printer software to get the other side. Print it out of ASA-CF. Heat up the brass pin with a heat gun and press-fit it. Bolts are countersunk 5mm flat heads. Drill a 5mm clearance hole in the door and secure the 2nd point.   

 

Feel free to use, modify, and distribute. Not for commercial use, please. 

Mirror_mount_rev5.2_FDM.STEP