[wheelhousebrewing]

My last batch came out with a pre-boil gravity far lower than what I expected.  (I do plan to recalibrate my efficiency with next batch).  But it got me wondering how much water dilution effects this outcome.

My current batch sparge process: I add around 5 gallons of water (at 170, though I read I should bump this to 190) to the tun after the first runnings complete.  Stir, sit and sparge until my desired volume is achieved.

Should I be more precise in how much water I add or is the impact not so great?

Thanks!

[gymrat]

How much water did you mash with?

[a10t2]

You should run the mash tun dry for each runoff. Otherwise you're intentionally leaving sugars behind.

[wheelhousebrewing]

I don't recall but the mash water was more than I had planned (Maybe up to 2-2.5qts/lb.  I used a two-step process and used 'boiling' water to get from the protein rest to the sach rest.  But here in Denver, my boil water temp is lower so i had to increase the volume).

I only need one runoff and I do let the first runnings dry out the tun.

[Jimmy K]

Yes, because all of the sugars are equally distributed in the sparge water. If you sparge with 5 gallons but only drain off 4, you're leaving 20% of the sparge sugars behind.

[Jimmy K]

I don't recall but the mash water was more than I had planned (Maybe up to 2-2.5qts/lb.  I used a two-step process and used 'boiling' water to get from the protein rest to the sach rest.  But here in Denver, my boil water temp is lower so i had to increase the volume).

When I correct mash temperature with boiling water, I reduce my sparge water by an equal volume. 

[gymrat]

So you had a thin mash then over sparged? Between the two that is a really high water to grain ratio.

[denny]

You should run the mash tun dry for each runoff. Otherwise you're intentionally leaving sugars behind.

Yep.  What you want to do is measure how much runoff you get from the mash.  Subtract that from the amount you want to boil.  The answer you get is how much sparge water to use so that you have nothing left behind.

[DrewG]

Yep.  What you want to do is measure how much runoff you get from the mash.  Subtract that from the amount you want to boil.  The answer you get is how much sparge water to use so that you have nothing left behind.

^
That

[wheelhousebrewing]

So you had a thin mash then over sparged? Between the two that is a really high water to grain ratio.

Well when you put it that way...  But hey, it's gonna be the richest 3.4% beer in town.

Muchas gracias to everyone for the feedback.

[fmader]

Yeah, what these guys are saying lol.

I use this batch sparge calculator. It works wonders for me. I do use 1.5 quarts per pound, and disperse the infusion volume they give me over the mash and sparge water. I try and keep my numbers close to quarter gallon increments....

http://onebeer.net/batchspargecalc.shtml

....and as per Denny's advise, boosted my sparge water temperature

[alcaponejunior]

You should run the mash tun dry for each runoff. Otherwise you're intentionally leaving sugars behind.

Yep.  What you want to do is measure how much runoff you get from the mash.  Subtract that from the amount you want to boil.  The answer you get is how much sparge water to use so that you have nothing left behind.

I guess I stumbled upon the approximate correct technique by accident.  This is what I've been doing, basically.  Wind up with about 6-6.5 gallon pre-boil, about 5 or slightly  less after (depends on how much hops, mostly). 

Drain mash tun till it's a slow trickle, then add sparge water, then drain again, then add sparge water, then drain final time.  OG works with beersmith II if I use 67% efficiency (top of design page input). 

Beers have been coming out fine since I made adjustments and figured it out.  Even before then, they were good but my OG was low.  Adjusting efficiency on beersmith was key (for me at least).

[denny]

I guess I stumbled upon the approximate correct technique by accident.  This is what I've been doing, basically.  Wind up with about 6-6.5 gallon pre-boil, about 5 or slightly  less after (depends on how much hops, mostly). 

Drain mash tun till it's a slow trickle, then add sparge water, then drain again, then add sparge water, then drain final time.  OG works with beersmith II if I use 67% efficiency (top of design page input). 

Beers have been coming out fine since I made adjustments and figured it out.  Even before then, they were good but my OG was low.  Adjusting efficiency on beersmith was key (for me at least).

Do you have a very small mash tun?  There should be no other reason to have to sparge twice.  And are you stirring well after you add the sparge water?

[alcaponejunior]

I guess I stumbled upon the approximate correct technique by accident.  This is what I've been doing, basically.  Wind up with about 6-6.5 gallon pre-boil, about 5 or slightly  less after (depends on how much hops, mostly). 

Drain mash tun till it's a slow trickle, then add sparge water, then drain again, then add sparge water, then drain final time.  OG works with beersmith II if I use 67% efficiency (top of design page input). 

Beers have been coming out fine since I made adjustments and figured it out.  Even before then, they were good but my OG was low.  Adjusting efficiency on beersmith was key (for me at least).

Do you have a very small mash tun?  There should be no other reason to have to sparge twice.  And are you stirring well after you add the sparge water?

Yes, and yes.  5 gallon igloo cooler mash tun (cylindrical, vertical).

I have a 5 gallon mash tun.  I usually sparge twice and stir in each time (and let sit a few minutes each time).  Total sparge volume (per run) about 1.75 gallons.  Similar to BS "recommendation."

Any tips on improving?

[denny]

I guess I stumbled upon the approximate correct technique by accident.  This is what I've been doing, basically.  Wind up with about 6-6.5 gallon pre-boil, about 5 or slightly  less after (depends on how much hops, mostly). 

Drain mash tun till it's a slow trickle, then add sparge water, then drain again, then add sparge water, then drain final time.  OG works with beersmith II if I use 67% efficiency (top of design page input). 

Beers have been coming out fine since I made adjustments and figured it out.  Even before then, they were good but my OG was low.  Adjusting efficiency on beersmith was key (for me at least).

Do you have a very small mash tun?  There should be no other reason to have to sparge twice.  And are you stirring well after you add the sparge water?

Yes, and yes.  5 gallon igloo cooler mash tun (cylindrical, vertical).

I have a 5 gallon mash tun.  I usually sparge twice and stir in each time (and let sit a few minutes each time).  Total sparge volume (per run) about 1.75 gallons.  Similar to BS "recommendation."

Any tips on improving?

Get a bigger cooler!