Goldfish Mirror - Side Mirrors

[Frank Lee]

...remember a time when car designers couldn't use aero-conformal headlights because of round/rectangular seal-beam lamp requirements.

I think that arguement against the round sealed-beams is largely bogus. Take most of the front-ends of vehicles with so-called aero lighting and if you wanted to, you could fit the round sealed beams in.

I for one am sad the round sealed beams went away. They didn't fog, haze, or yellow. They cost $5 to replace (why do dinky headlight bulbs cost more than an entire sealed beam assembly?) and they were easy to replace- no tearing the entire front fascia off to get at them. They put out a nice beam. And they were practically a universal fit. You could buy them at virtually any store in America.

[kach22i]

Originally Posted by graydonengineering

. A little nuts I know but just thinking outside the box here.

Not nuts at all, this is how idea are born.

Yesterday I sketched up a mirror which is perforated, allowing built up front face pressure to flow though. Might work, but somehow just not very sexy, and deterioration of the mirror surface would always be an issue.

I can just imagine droplets of water resting in the tiny holes, waiting for night fall when they can freeze, expand and do destruction.

[kach22i]

Originally Posted by Frank Lee

Take most of the front-ends of vehicles with so-called aero lighting and if you wanted to, you could fit the round sealed beams in.

I say this is true for a good 50%.

The rule of no headlight covers over the old round headlights is the one which irked me. The European sports cars, and even some Japanese sports cars just were not the same.

Headlamp - Wikipedia, the free encyclopedia

[jakobnev]

I think Volvo had a segmented mirror on a concept car a few years back, but my google-foo is failing me right now. It was several mirror-slits behind each other, correctly paced and angled to give a single image.

[Frank Lee]

Yesterday I sketched up a mirror which is perforated, allowing built up front face pressure to flow though.

It would behave just like screens, which at speed act like solids re: air flow.

[graydonengineering]

Originally Posted by Frank Lee

It would behave just like screens, which at speed act like solids re: air flow.

Yes, the key here would be to make the holes large enough that the flow through would exist throughout the intended use velocity. I have considered making a mirror my polishing some perforated steel. It would be very labor intensive to get it up to mirror shine. It would give you a "flies eye view". Your brain would need to fill in the blanks.

[Vekke]

Here is my thoughts. Mirror drag savings can be in the range of CD 0.01 or even more if your current mirrors are bad. To reach this with your own mirrors you should avoid few things and try to do what you can to make as sleek as possible.

1. Size is bad. So try to make mirrors as small as possible. I will use wideview mirrors in my Lupo. Smaller mirrors also reduce the frontal area. My Lupos mirros have about 1/3 of the original mirrors size and the original ones were already pretty small.
2. Shape. Mirrors should have the teardrop shape, because that is optimal. If you can build there the sharp teardrop end its even better. There might be even better shapes for mirrors if you study them at wind tunnel but best quess is teardrop shape.
3. Position is also important. Now this is my own thinking here. I think they should be as low as possible if you attach them to doors apillar corner. Reason is simple all the flow will come to that "mirror" corner from the hood and windshield so you dont want to disturb it more than you have to. In almost all modern cars the "leg" of the mirrors is as low as possible. If you dont care about the visual looks so much you can build it even lower.

Few pictures of the current state of my mirror project, scroll to the right for more mirror images. Tomorrow the story will continue with more images.
https://www.facebook.com/media/set/?...type=1&theater

[cfg83]

Vekke -

If I were starting from scratch I would get some of these snowmobile mirrors :



They are small, 2.5"x4", but they are *convex*, so I think they would have a good field of view.

CarloSW2

[Vekke]

Mirrors I use are convex motorcycle "wheelie" mirrors ment to be attached to the handlebar. Square mirrors wont work what I have planned to try. So target is to build that boattail behind the mirror on round mirror is easier to cover.

[kach22i]

Originally Posted by cfg83

I did a version of this by making an "Easter Egg" rear view mirror :

CarloSW, that is what we call "out of the box".