This is what the inside of my helmet looks like, I painted it black and it's gotten some grey primer inside over time, hence the cloudy look:
I glued a single rare-earth magnet to the center top right above the eye ridge using just CA glue:
Next I took a strip of metal I bought from the hardware store and bent it by hand to match the shape on the inside. The metal cost about $4 for a 3' strip and is about 3/4" high:
Now I'm using a red visor which came with my helmet and in this photo you can see how it's only held in place by tape for fitting purposes:
And this is how it looks from the inside. The magnet holds it in place and I'm able to move it around just a bit to fit better. Now I might grind the edges down but honestly I've tried to have it hit my head and at this point I can't manage it, so I figure why fix something that isn't broken.
From the outside it looks like this:
But notice there is a gap around the nose. I hope this allows enough airflow to minimize fogging. And the only way you can see this gap is to look at the helmet from the top down. I'm 6'4" so that won't happen too often:
All in all I'm very happy with the single magnet. This is an easy way to pop in different visors and also to just permantnly attach a single visor as far as I'm concerned.
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