Final volume calculations

[Evil Jalapeno]

Noob question (I've only done one all-grain batch so far), but how many liters are you supposed to finish with after the 60 min boil? 20L?

[Chris Craig]

I'd shoot for about 21 l.  That's how much your keg will hold.  It's a function of your boil off rate.  That's going to take some time to figure out.  If you're using propane, then I'd start with a 4-litre boil off rate in your calculation.  So, if you want 20 l of wort:

Start with a pre-boil volume of 27 l
Boil for 60 minutes.  You'll lose 4 l if your boil off rate is 4 l/hr.
Chill -- you'll lose 4% to shrinkage as the wort cools.  23 l left.
Siphon to the fermenter.  You'll likely lose another 2 l between what's left in your kettle, and what you can't get out of your fermenter after the beer is finished.

That leaves you with 21 l to drink

You should check out BeerSmith.  It's great for doing all these calculations for you.

[Evil Jalapeno]

I'm not sure if I posted the question in the wrong section or if it was moved, but I originally wanted to know the final volume of the Black Like Your Heart IPA v2 recipe posted in the Tried and True section.

That being said, thanks a lot for the info. I do have BeerSmith, but still have longs ways to go to understand it perfectly!

When I did my first all-grain, which was the Belgian Dubbel kit from OBK, I followed BeerSmith calculations, but ended up with about 3-4 litres less than what I had originally expected. I simply topped it off to 20L. Is that a no-no? My OG was pretty much bang on after adding water, but I was pretty confused (still am!) as to what happened.

I'm at work right now, but I can copy/paste my brew steps later. Perhaps someone can find what I did wrong from these steps?

[Chris Craig]

Your question isn't really specific to a certain recipe.  It's the same for any recipe, so I moved this part of the thread because I thought it would be more useful to everyone here. 

If you were low on your post-boil volume, but hit your gravity after topping up with water, then you either hit your estimated pre-boil gravity, but boiled off too much, or you overshot your pre-boil gravity AND undershot your pre-boil volume.  There's nothing wrong with adding water at the end of the boil though. 

[Evil Jalapeno]

Your question isn't really specific to a certain recipe.  It's the same for any recipe, so I moved this part of the thread because I thought it would be more useful to everyone here.

*thumbs up*

If you were low on your post-boil volume, but hit your gravity after topping up with water, then you either hit your estimated pre-boil gravity, but boiled off too much, or you overshot your pre-boil gravity AND undershot your pre-boil volume.  There's nothing wrong with adding water at the end of the boil though.

Now that you mention that, I remember that my pre-boil gravity was ok, and so was my pre-boil volume. I must have simply boiled it too much. I guess I'll try turning the propane down a bit next time.

Thanks again!