Primary fermentation and cold crash.

So I have been doing alot of research into this and I would like some more opinions on these two areas.

1. How long to do primary fermentation? I heard 2 weeks is a general good for ales but I have heard up to 4 weeks in primary. What is a good general guideline?

2. I am going to start cold crashing and was wondering how long I need to do it to have an effective outcome? I do have a chest freezer with a temp. regulator and plenty of room so it is easy for me to do.

As always, thanks for the help guys.

1. I personally try to stick to at least 3 weeks in the primary. For me, thats the sweet spot. Enough time for the yeasties to finish, but still satisfy my impatience.

2. I usually only cold crash for a day or so. But longer will not hurt.

Should be almost completely fermented out in a week with a good starter, i only transfer to a secondary for fruit additions, dry hopping etc. So for me 3 weeks primary otherwise 1 week then 2 weeks secondary.

I don't cold crash anymore, I used to when i force carbed but now i prime in my kegs, just trimmed the pickup tube a bit. I will normally just put the carboy in place where i need to transfer the day before in case i stir things up moving it. Now when i did cold crash i had an old fridge i kept on the colder side and let it sit in there 24hours. It sat on a stand so when i transferred i could do it right from the fridge into my keg. If your bottling/priming in a keg i wouldnt bother cold crashing, of course this is my opinion and my wife says its always wrong.

You should leave the beer in the fermentation chamber until its finished. I know that sounds *****ey but that's how you do it.

How do you know it's done? The gravity hasn't changed in 3-5 days is a good indicator that the yeast has finished fermentation. However, that doesn't necessarily mean its done. If your process isn't perfect or something happened to negatively effect the beer you may want to leave it alone for a while longer. Some of the components that make beer taste bad are volatile and may naturally exit the beer with a little time. Also, some of those nasty flavor components may settle out of the beer with time, like when there's too much yeast in solution.

Cold crashing is great for clarifying your beer and helping low flocculating yeast fall out of solution. I usually cold crash 2-4 days. Remember though sometimes cold crashing g can make some of the compounds you want in your beer to fall out of solution too. Just like leaving your beer in primary too long can allow some of those amazing Belgian yeast esters to escape too.

1) Only the yeast and your hydrometer can answer that question.

2) Assuming you're going for clear beer here, it'll depend on the yeast and the recipe. Some yeasts will drop clear fairly quickly with no cold crash, others may take a lot longer.