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What volume to use for measured pre and post boil?

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h22lude

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On my brew day report from BeerSmith I have measured and estimated pre boil volume and post boil measured and estimated volume.  My question is, at what temperature does BeerSmith calculate each?  I BIAB so my total volume is used to mash.  This batch I needed 8.52 gallons to mash in.  Then BeerSmith calculated my pre boil volume to be 8.11 gallons.  Does BeerSmith calculate this volume at mash temps or at room temp?  Same with post boil volume.  BeerSmith calculated my post boil volume to be 6.31 gallons.  Does BeerSmith calculate post boil volume at near boiling or at room temp.  Since water volume increases with heat, if I measured my pre boil volume at room temp but BeerSmith calculates it at mash temp, my figure wouldn't be equal to what BeerSmith estimates.

I calibrated my sight gauge using room temp water.  I then heated that water to mash temp and marked the increase on a card stock piece of paper.  I then heated that water to a boil and marked that increase on the piece of paper.  So when I am done with my mash and removed my grains, I can use that piece of paper to tell me how much water I have if it were at room temp.  So for my pre boil volume, should I be entering the volume at my mash temp and BeerSmith has adjusted for the heat increase or should I be using my piece of paper to get what my pre boil volume would be at room temp?
 
BeerSmith calculates the volumes "at temperature".  So your 'mash in' volume includes the expansion factor for temperature.  Same holds for pre-boil and post-boil volumes.  It would not make sense to chill your pre-boil wort down to room temperature just to heat it back up to boiling.

I have a dip stick that I measured and marked for my kettles and use that to measure pre- and post- boil volumes.  Since I do BIAB also, I measure the water in cold (at room temp) and take the target BeerSmith gives me and reduce it by my expansion factor for my initial measurement into the kettle.
 
Just to put it into volumes...

1) I mash in with my full volume (no sparge) of 8.52 gallons.  That volume should be calculated at mash temp?
2) The pre-boil volume after mash and removing grains is calculated at mash temp as well?
3) The post-boil volume after boil is calculated at near boil temp?  Or is this calculated at chilled temp?
4) The batch volume would then be calculated at fermentation temp?

I calibrated my sight gauge at room temp.  I run my RO system the night before for the amount BeerSmith tells me.  So if that is figured at mash temp, my volumes have been off since my mash in volume is calculated at room temp.

Like I posted in my original post, I have a card that gives me the adjustment for temp.  I have a line for where the room temp volume is and then a line for the mash temp volume and boil temp volume.  If BeerSmith mash in volume is at mash temp, what I'll have to do is put the mash temp line on the card at the correct volume then fill the water (at room temp) to the room temp line on the card.  Once I heat it up to mash temp, it should match with the volume BeerSmith calculated.
 
h22lude said:
Just to put it into volumes...

1) I mash in with my full volume (no sparge) of 8.52 gallons.  That volume should be calculated at mash temp?

This is correct.  The volume calculated in BS2 is for water at strike temperature

2) The pre-boil volume after mash and removing grains is calculated at mash temp as well?

Correct

3) The post-boil volume after boil is calculated at near boil temp?  Or is this calculated at chilled temp?

Correct.  If you look at the 'Vols' page you will see the post boil volume and under that the volume of shrinkage due to cooling.  When you follow the water balance, you will see that the ending volume of wort to fermentor + loss to trub and chiller = post boil volume - shrinkage.

4) The batch volume would then be calculated at fermentation temp?

Correct

I calibrated my sight gauge at room temp.  I run my RO system the night before for the amount BeerSmith tells me.  So if that is figured at mash temp, my volumes have been off since my mash in volume is calculated at room temp.

Like I posted in my original post, I have a card that gives me the adjustment for temp.  I have a line for where the room temp volume is and then a line for the mash temp volume and boil temp volume.  If BeerSmith mash in volume is at mash temp, what I'll have to do is put the mash temp line on the card at the correct volume then fill the water (at room temp) to the room temp line on the card.  Once I heat it up to mash temp, it should match with the volume BeerSmith calculated.
Click to expand...
 
I changed the shrinkage due to cooling from 4% to 0%.  All my volumes went down by the same amount.  Wouldn't that mean that all volumes are taken at boil temp?

Batch size stayed the same at 5.5 gallons
Strike water went from 8.71 gallons at 4% to 8.47 gallons at 0%
Pre-boil water went from 8.11 gallons at 4% to 7.86 gallons at 0%
Post-boil water went from 6.31 gallons at 4% to 6.06 gallons at 0%

The only thing measured at room temp is the batch size.  With 4% in the shrinkage due to cooling, everything seems to be at boiling.  Removing that 4% brings everything down to room temp.  Am I looking at this incorrectly?
 
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