Two batches in - volume issues

[hopsnhawks]

howdy, built myself a sweet mash tun using a rectangle cooler and stainless steel braid, have now made two batches and have some issues that I would like some feedback on

I am using the two equations from Palmer's "How to Brew" to determine water volumes:

Initial Infusion Equation:
Strike Water Temperature Tw = (.2/r)(T2 - T1) + T2

Mash Infusion Equation:
Wa = (T2 - T1)(.2G + Wm)/(Tw - T2)

I am achieving the correct temperatures alright but I am losing volume somewhere, both batches I have only been able to lauter around 5 gallons from the tun after putting in 8+ gallons of water through the whole process and am ending up with completely dry grain beds by the time lautering is finished

I will assume I need to just prepare more sparge water (only used ~2 gallons both times) and just keep flushing the grain bed until I get 6.5 gallons out but it seems I am losing a ton of water somewhere

on a similar note my OG is much lower than predicted both times (~1.045 instead of ~1.055)

any pointers from the experts?

 

[GrogNerd]

more info needed: what are the values for your variables?

 

[forstmeister]

I usually need 9 gallons or so depending On the grain bill. It took me several batches to figure out my volumes correctly.

Are you batch sparging or fly sparging? Your setup would probably benefit more from a batch sparge since you are using a hose braid instead of a manifold or a false bottom.

 

[tooldudetool]

I find the online calculators easier to use, there are plenty out there and I believe they are based on the same numbers you are using. I agree that you should try batch sparging, personally I don't understand why anyone would fly sparge. It takes me about 20 minutes to collect my second runnings and i regularly get 85-90% mash efficiency. I use 1.6 quarts per pound of grain for the mash, and assume .15 gallons of absorption per pound of grain to figure out my first runnings volume. Subtract that from your desired starting boil volume and use that number for your sparge water volume.

 

[hopsnhawks]

thanks for the replies

I was using 1.3qt/lb ratio with 9.25lbs grain so added 3gallons of water to mash, then I used 1.75gallons strike water to bring the temp up to 170 before lautering, unfortunately I couldn't reach that temp so kept adding hot water so used up most of my sparge water before I needed it, the last 5-10minutes of the lauter there was a dry grain bed which I know is frowned upon

I never took into account the grain absorption, how do you account for that? I was thinking of spending the money on BeerSmith or something so I don't have to stress about the numbers at this stage and can learn what they all mean through experience, are there any recommended free ones?

I am doing what I believe is a continuous, or fly, sparge but if batch is smarter with the hose braid then I should look into that, any pointers for batch sparge?

 

[worthogg]

check out http://hbd.org/cascade/dennybrew/. all the info you need is right there. as for free apps, Brewpal and Spargepal are both free I believe and work well for what they are intended for. maybe someone else will chime in with a couple others as I use Beersmith mostly.

 

[GrogNerd]

thanks for the replies

I was using 1.3qt/lb ratio with 9.25lbs grain so added 3gallons of water to mash, then I used 1.75gallons strike water to bring the temp up to 170 before lautering, unfortunately I couldn't reach that temp so kept adding hot water so used up most of my sparge water before I needed it, the last 5-10minutes of the lauter there was a dry grain bed which I know is frowned upon

I never took into account the grain absorption, how do you account for that? I was thinking of spending the money on BeerSmith or something so I don't have to stress about the numbers at this stage and can learn what they all mean through experience, are there any recommended free ones?

I am doing what I believe is a continuous, or fly, sparge but if batch is smarter with the hose braid then I should look into that, any pointers for batch sparge?

highlighted section was your mash out?

mashing out involves stopping the conversion process with 168° water so that your final product doesn't dry out. and it's not always necessary, depending on the style. heating the wort to boiling will stop the conversion in your first runnings.

OR, your sparge water can act as your mash out infusion if that brings the mash temp up to 168°

batch sparging is done by draining the tun "dry" for your first runnings and adding more water. you don't really have to worry about a dry grain bed, not like you do with fly sparging.


Beersmith uses 0.9600 fluid oz water per oz of grain lost to grain absorption. in your case 9.25 lbs = 148 oz * .96 = 142.08 fl oz / 128 oz = 1.11 gallons absorption

 

[wetzie]

I use this site for calculations, it has helped me a lot.
http://www.rackers.org/calcs.shtml
I usually hit my target with very little needed to do to adjust.
I use a stove top mash tun with a false bottom and batch sparge.

 

[GrogNerd]

I use this site for calculations, it has helped me a lot.
http://www.rackers.org/calcs.shtml
I usually hit my target with very little needed to do to adjust.
I use a stove top mash tun with a false bottom and batch sparge.

all kinds of calculating goodness there. I had forgotten that site

good job, wetzie!

 

[stpug]

To me, it sounds like you're fly sparging (a.k.a. continuous sparging) using a rectangular cooler with a stainless steel braid. If this is true, then your efficiency is likely sub-par due to your setup. A rectangular cooler with stainless braid is almost exclusively used for batch sparging; which is not to say it can't be used for fly sparging, but it's much better suited to batch sparging.

I just brewed a batch last night:
11.8 lb grain
8.4 gallons of total water used
6.75 gallons of wort in preboil

I should have had more water/grain absorption than you, and I yielded about 1.75 gallons more in my BK. You are definitely leaving some liquid (likely, high sugar wort) somewhere.

If you are fly/continuous sparging, then I would highly recommend to try batch sparging next time.

 

[hopsnhawks]

good stuff, appreciate all the calculator cheat sheets

take home message - switch to batch sparge and climb my way back up to fly sparge

last question, when I drain the grainbed the two different times for batch sparging, do I need to worry about drain rate or just open the ball valve completely?

 

[stpug]

Denny says to open it up and drain as fast as you can/want. His setup is very much like yours.

My setup, which is quite different than yours, is best when I drain at a moderate pace - but not breakneck speed. I will typically empty a 5 gallon water cooler full of mash in about 5-7 minutes, if that's any help. If I open my 1/2" valve full bore then my grainbed compacts and I get a stuck sparge (which is easily resolved by stirring, vorlaufing, and draining again, but it slows me down and is more work than simply slowing my drain speed).

 

[worthogg]

Denny says to open it up and drain as fast as you can/want. His setup is very much like yours.

My setup, which is quite different than yours, is best when I drain at a moderate pace - but not breakneck speed. I will typically empty a 5 gallon water cooler full of mash in about 5-7 minutes, if that's any help. If I open my 1/2" valve full bore then my grainbed compacts and I get a stuck sparge (which is easily resolved by stirring, vorlaufing, and draining again, but it slows me down and is more work than simply slowing my drain speed).

I believe I remember reading that Denny actually says to start the vorlauf very slowly at first; like it should take a couple minutes to get that first quart or so. After that, you can slowly open the valve until you reach full bore. I think that this helps prevent a stuck sparge by setting the grainbed well initially. Or something to that effect.

 

[Skarekrough]

Final Volume in Fermenter
+
Boil Off Volume
+
Water Lost To Grains

The first two are pretty easy to figure out; for five gallon batches you're looking for around 5.25 gallons in the fermenter (.25 loss to trub) and boil off is usually 1.0 gallons an hour on average. It may be more, may be less.

Water lost to grains can be calculated as .06 to .12% water per pound of grains. This isn't always a set number as the crush can vary. The more consistency you have with them the better you will be able to calculate this.

I tend to mash in heavy as the last great variable for removing water is the boil, which you can go long with if you get too much wort (just don't add your hops yet).

Also, there's a 4% loss for cooling of wort. I rarely calculate that though, mainly because I'm lazy.