What happened to my mirror, Why, and what's the fix?

Well, friends, I tried it. Our friend IMICHABOD gave me his broken pieces, so I got a chance to try my idea. Two things:

1. This mirror wasn't Heated/Powered/Illuminated, so I used a BOLT for this trial run.

2. I wanted to use tools and techniques any of us ought to be able to duplicate. No fair taking it to a buddy's machine shop.

The piece the retainer edge broke off of is tapered. It's attached to the body mount with four Allen Head screws. Also means Velvac could ship that out as a repair part, but anyhow... Removed the four screws with 5/32" Allen Wrench. Velvac used Loctite RED, an assembly-grade product. A little tough getting them to break loose, but I have an alternate plan for that. I found that a 1/2" hex nut will tap down into that taper from the top. Getting it to line up with a bolt centered up from the bottom is a little touchy.

You can see in the first pic, where I whitened three places:

1. Alignment marks from tapered pivot to body mount; 2. Tab on body mount to prevent Arm from swinging too far folded and hitting body, 3. Last little bit of the retaining edge. Shows from about 2:00 to 5:00 position in the pic. This should go all the way around. Note: The 1/2" nut is already in place down in the taper, you can see the hole and hex edges here.
Broken Pivot showing Allen Screws
Next pic is the assembly drawn back together. I put a 3/4" flat washer on top of Velvac's retainer and a 1/2" flat washer on top of the 3/4" to keep the bolt head from passing through it. The 1/2" washer bottoms on the pivot where the retaining edge broke off. This puts the original retainer where it originally was, so the mirror can be folded yet should stay extended on the road.
Mirror Assembled
Last pic looks into the back side of the body mount where you can see the top of the 1/2" nut I tapped into the tapered hole of the pivot, and the upper end of a 1/2" by 3" hex head bolt up from the bottom, where the spring is compressed. Threaded end of bolt is sticking out of the nut by about the amount the spring had to be compressed, about 1/2"
Nut and Bolt Threads
After removing from Vehicle, tools needed: 5/32" Allen; 3/4" wrench or socket; flat and round files (remove what's left of retaining edge, slightly enlarge 3/4" washer hole to fit over the filed-down retaining groove); hammer to tap nut into tapered hole in pivot

Bill of materials: 1/2" bolt, 3 or 3-1/2" long; 1/2" nut and flat washer; 3/4" or 7/8" flat washer" tube of Loctite Blue... Hardware should be under $5.00, about $5.00 more for Loctite

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