confused about fly sparging and amounts

[megavites]

Ok,
If I'm going to do an AG reciepe with 16lbs of grain for a 5 gallon recipe, and use a 1.25qt/lb ratio for mash in, I wind up with 5gallonsat mash in.
Everything I've read says, sparge water amount should be 1.5 times mash in amount, in this case, 7.5 gallons, for a total of 12.5 gallons??
I know I'm reading something wrong here.This is my first AG reciepe, so pls. forgive me.

I'll be using the AG kit from Northern.(10 gal w/false bottom, fly sparge arm)
do I need to account for anything due to false bottom?

 

[Lil' Sparky]

If you mash with 1 qt/lb then you're sparge will typically be 2 qts/lb. If you're mashing thinner with 1.25 qt/lb, then you're sparge volume will have to be adjusted accordingly.

 

[megavites]

Ok, if the recipe calls for collecting 6.5 gallons, and your suggesting 1qt/lb, ie 4 gall.mash in, should I fly sparge with an addt'l 2.5 gallons?

 

[Ó Flannagáin]

I haven't done an all grain yet, but 16lbs seems like a lot of grain for 5 gal. Probably would need to adjust everything to work with that amount. I honestly have know idea though, just seen most AG recipes with 11-12lbs of grain.

 

[perry]

I "fly" sparge universally, and my rule of thumb is to heat (and sparge with) as much water as I expect to have in the boil. This assumes that most of those mash-gallons will run into your boiler first. (16 lbs is a huge amount of grain for a five gallon batch, assuming a 70-80 % efficiency, and if you plan to sparge with 12 gal. you may want to consider doing another "small beer" with the second runnings.... again, depending on your mash efficiency.)

I shoot for two gallons in the kettle over what I want my final volume to be, and boil for an hour and a half.

I usually lose 1/2 gal per 1/2 hour of boil time... Boiling 12 or more gallons down to 5.5 would take forever and result in a much darker color as well.

Hope this is helpful. -p

 

[ajf]

The thing you're missing is that the grains will absorb quite a bit of the water.

According to Promash, 16 lbs grain will absorb about 2 gallons water, but I have never verified the absorbtion rates so I can't guarantee this is accurate.
In fact, I never measure my mash or sparge water volumes because I find this too complicated. I add grain and water to the mash till it looks right, and then sparge till I have about 7g in the kettle. At this point, the gravity of the wort going into the kettle is approaching 1.010. I know this won't be much help to you, but the ratio of sparge to mash water isn't critical, and neither is the ratio of grain to water in the mash providing it is somewhere in the region of 1 to 1.5 qts per pound.

-a.

 

[The Pol]

I have never gotten very scientific with the sparge water quantity... I just fill the liquor tank and let it run. If I have too much, oh well, I can clean with it too!

The Pol

 

[megavites]

Ok,
this is a 16lb Ruination IPA clone.I need to collect 6.5 gallons. So mash in at 1qt/lb will be 4 gallons.
Now, do I:
a.) simply lauter with an addt'l 2.5 gallons?
b.) lauter until I hit a certain gravity.
c.) lauter with what I read in the books (1.5 times mash in amount)

 

[megavites]

Here's the setup I'll be using (10 gal) 1/2 way down the page

http://www.northernbrewer.com/allgrain.html

 

[Lil' Sparky]

Ok,
this is a 16lb Ruination IPA clone.I need to collect 6.5 gallons. So mash in at 1qt/lb will be 4 gallons.
Now, do I:
a.) simply lauter with an addt'l 2.5 gallons?
b.) lauter until I hit a certain gravity.
c.) lauter with what I read in the books (1.5 times mash in amount)

Here's the deal with really big beers like that. If you're using 16 lbs of grain / 5 gallons, the formulas will have you collecting more wort than 6.5. If you do, then you'll have to boil longer to get more evaporation. If you don't, you'll have crappy efficiency.

For example, if you use Papazian's equations, you would:

mash with 1 qt/lb = 16 qts = 4 gal
expect .1 gal/lb absorbtion = 1.6 gal absorbed, leaves you with 2.4 gal
sparge with 2 qt/lb = 32 qts = 8 gal
total volume in kettle = 10.4 gal
typical 1 hr boil, 1~1.5 gal evaporation

So clearly you've got too much wort (~9 gal) still. You can boil longer, or sparge with less, or both.

If you want to stick with a 60 minute boil, I would say sparge with ~ 4.5 gal, expecting lower efficiency. This would get you in the 7 gal range at the start of the boil. After boil you would have a little less than 6 gallons. Plus, if you use whole hops, you may lose a little more to hop absorption.

BTW - you should enjoy the setup you got. Most have given it good reviews.

Cheers and enjoy!

 

[megavites]

Sparky,
thankyou for the input. That's what I was looking for. My head is kind
of spinning with all the books I've been reading.

This recipe is from the BYO 150 clones issue. I can't wait to try it!

Prost!