Help diagnose my foam issue...

Had my first keg set on 40F for 2 days at 30psi. Shook the holy hell out of it the first day and let it set with the gas on for 2 days. Dropped the pressure after 2 days to 12 psi and have a 6' hose with picnic tap. I have bled the pressure, with the gas turned off, multiple times last night and it has not been moved during this time. Came home from work today, bled the pressure which was not much, hit the tap and a bit of beer started to trickle out. No foam. Turned the gas to 12 psi, all foam. I know how to pour.
What gives? Beer line too short? Too much pressure? It is the standard 3/16 size.

personally i would give it a few days to absorb. For my carbing i leave it on serving pressure for a week

Try 30psi for 24-36 hours, then drop to serving pressure for 4 days. Or better yet, Serving pressure for 2 weeks.

I tried the shake the hell out of it method, and it is NO substitute for some patience.

on my system, 6 feet is not enuf line for 12psi. I run 8 feet of tap line to my cobra taps and get a good pour.

Sounds like it was overcarbonated by your method. You sort of mixed two methods together.

You can either jack the psi up to 25-30ish and shake the keg to get the carbonation up, after which you turn down to serving pressure and let rest for a couple hours
or you jack the psi up to 25-30ish and let sit for 36-48 hours then turn down to serving pressure.

By shaking it at 30psi you probably were close to where you wanted to be. When you left it at 30 for 2 more days you ended up with way to high a carb level. Just got to bleed it down for a couple days I would think.

Is your tap at the same temperature as your beer?

my beer is at around 10 psi I think with 5 feet of hose in my kegerator. My first pour into a pint gives me about 2/3 beer 1/3 foam. My second pint pours perfectly so I attribute the 1st pint's excessive foam to the temperature difference. The first pour goes through a warmer tap and that seems to draw out the CO2. Since the first pour essentially cools the tap the second and subsequent pours are perfect.

So maybe it's possible depending on where your tap is that the problem isn't pressure...but temperature or rather a big temperature difference that the beer flows through causing the CO2 to dissolve out of solution.

Cheers.

Temperature difference , as AJ stated, makes a difference, but since you are using a plastic picnic faucet, here's a few tips.
Try a longer line, not every line has the same resistance per ft. My lines avg 8' for 12 psi.
Make sure you are opening the faucet all the way.
Let the keg sit at serving pressure for a day or two. I usually get drinkable carbonation at one week cold and on the gas, at two weeks it is ideal, like Arkador said. When I try to shake kegs it rarely works out as well as I'd like.
-Ben