Window defogger/defroster

[SteveHRV7]

How many of you have installed some type of window defogger/defroster?

I am at a stage where if I want to install some type of fan or airflow directed up onto the windshield I should do it now. I searched the threads but most of the posts are several years old. There seem to be 4 possibilities:

1. Don't install anything - its not a problem
2. Passive heating - warm air convects up through a hole in the glare shield
3. Active heating via airflow from a small scat tube directed at the window
4. Active heating via a fan of some type

Recommendations, advice, thoughts...

Thanks!

[L.Adamson]

I have a 12 volt computer fan mounted under the glare shield (slider). No ducting, although I made a triangular shaped hood, which I don't use. Whenever the windscreen has fogged up during taxi, I flip on the switch, and it immediately clears. I'll just assume it's better to have one, than not.

L.Adamson --- RV6A

[kevinh]

I went for your option #3. And _very_ occasionally I develop fog on the windshield after engine start. No problem - I just crack the canopy and do my preflight checks. By the time I've done my runup the fog is gone.

[sbal0906]

How warm do the electronic components in the instrument panel get? Can a fan be used to draw warm air from the instruments toward the windshield?

Cheers,

[yakdriver]

I have a 3" computer pancake fan and it works great. It is mounted over the radios so it pulls a little heat off them plus the heat from the heater. Don