Rule of thumb quantity-full vol boil

[Nick667]

Ive got a new pot, 45lts, and want to mark the side of it with volume marks before I use it.
I havent used the Brewmate software to do full volume boils as I had to top up during the boil.
Is ther a ruke of thumb quantity to give me 24litres after a 660min boil and chilling.
Is it around 32lts?

 

[Rocker1986]

Not really.. you'd have to work it out yourself as there will be variances between different systems. One way would be to fill it up with water to a certain volume and boil it for an hour, then measure the volume after it's chilled back down again. Looking back I wish I'd done that myself, instead I just brewed a few batches and roughly worked it out that way, although once I did it was obviously fine as I knew how much water/pre-boil volume and boil length was needed to achieve my desired batch size.

 

[rude]

Sounds good I go for 34 -32 L boil for 90 mins

Fill a cube up 23 L the rest is leftover say 3 - 4 L

I boil hard though most people go for 10% evap

 

[technobabble66]

for a 30-40L urn, i think the ballpark is ~1L per 10mins boiled off, with a moderate rolling boil.

However, there's lots of variables, and the difference alone between a slight rolling boil and a vigorous rolling boil is huge.
So basically you have to do a test batch and determine the estimate for your specific system.

FWIW, i prefer to overestimate the boil-off, and end up with less volume of (more concentrated) wort, as i can always add water later to bring the volume up to target volume when pitching. I'd commonly do 25-26L (in the FV) batches where i boil down to 22L to squeeze into a cube, then add the 3-4L water when i pop the cube and pitch.

 

[Danscraftbeer]

Notes on your experiences is very helpful when I worked this out. Many variables as mentioned so its about getting a regular pattern to your technique. I do 40lt brews. Pre boil is usually 55lt (Keggle) but sometimes its more and I have boiled the excess in a pot on the stove as well until its reduced and can all fit in the keggle then start the boil timer. The wort boils down to the 45lt mark at end of boil (after medium rolling boil). The chilled wort shrinks about 1 lt in size. 4lt trub left after decanting. = 40lt reliable now. Its basically chefs judgments that you refine with repeated brewing. When I first started all grain I undershot and overshot a few. It still made good beer but It feels great to hit all targets as planned after all the work. Always a few sware words and disappointment if I don't because you then have to make the adjustments to the software and see how much it didn't work out to plan etc.

 

[Nick667]

Thanks for your input.
When I was topping up the boil and got it quit well at 24lts after cooling but not always and the boiling brew was lapping at the gunwales by the last top up.
P.S. can someone give me a calculator for a dip stick type calculation eg vertical measurement for volume. I have found one but want to double check before I put some ding marks in the pot.
Thanks.

 

[fletcher]

for what it's worth, i'd consider getting/borrowing a large electronic scale to measure the liquid, and not use a pre-marked pot or jug unless you know its accuracy. measure the liquid's volume by weight as you place it on the scale inside your pot.

 

[Danscraftbeer]

Also. If your making top ups I see no reason at all to top up the pre boil. Especially if your pushing the limits there.
Just top up the final wort. Either at flame out or chilled.
I only marked the outside of the keggle with texta at 5lt increments. It works for me.
The reason I have a larger pre boil is because I sparge more which gets a better efficiency. I make no top ups.

ps. I assume you mean top ups are just water? not sparges? I may be misinterpreting here. :unsure:

 

[rude]

Youre top ups still need to be boiled 10 - 15 mins wouldnt they

I do any ways

 

[Danscraftbeer]

You could just add boiled water at flame out to the correct volume.
and I forgot. Don't put dings in your pot! You will regret that. Etching if anything on the inside or removable texta on the outside. I vote the texta on the outside.
I may re study the threads here and do an etching some day. Like this: http://aussiehomebrewer.com/topic/89085-kettle-volume-etching/

 

[spog]

Ive got a new pot, 45lts, and want to mark the side of it with volume marks before I use it.
I havent used the Brewmate software to do full volume boils as I had to top up during the boil.
Is ther a ruke of thumb quantity to give me 24litres after a 660min boil and chilling.
Is it around 32lts?

Marking the volume of your kettle is simple,tip 5 litres of water in let it settle and then mark the level,continue by adding 5 litres ( or whatever amount ) on top and mark again.
Marking the volumes for boil off won't work.....too many variables.
Your final volume can only be determined by using your rig ,taking notes and doing numerous brews to figure out boil off,absorption etc.

 

[Nick667]

I have a new pot so I hope not to top up again.
45lts.
I put ding marks on the old pot with a nail punch from the inside and it worked well.
My smaller pot was 32 lts and if I could top up with boiling water close to the end of boil I could just get 24lts cooled into the fermenter including a couple of lts of crud off the bottom but I was really pushing it with the boiling sticky stuff slopping over the rim at times.
Now, with my new pot, I am hoping to go further the man (me) has gone before. To discover new beer horizons.
Will kick it in the guts this weekend and see how I go.

 

[spog]

I wouldn't bother with adding extra water to the boil as it raises the risk of a boil over because of too much in the kettle.
If you have another pot that you can pre boil water in,and using your standard method of a boil add the pre boiled water to the fermentor to make up your desired volume/gravity.
When i say pre boil i mean,If you have the gear to do a pre boil of water of say 10 litres of water and let it cool to yeast temp you can add this to make up the volume.
The pre boil would need to be done well ahead of the brewing process, if you choose to boil for 15 mins to kill any nasties and then let cool to pitching temp.
Perhaps try boiling some water in a large pot the night before then cover it and let it cool overnight ?
Any left over water can be used for cleaning etc

 

[stm]

OP now has a bigger pot.

 

[spog]

Win,win.