Dead space - stroke water volume/grain bill increase?

[wushurichard]

Hi,

I have a question regarding dead space in an all grain brew.

So, I measured the dead space of my boiler and mash tun and it is a total of approx 1.75 gallons (1-boiler, 0.75 MT). I was wondering, to account for this do i increase my strike water volume by 1.75gal? and if so would i need to increase my grain bill to accordingly?

Many thanks,

[Fil]

Wow what size boiler/tun are you using, I first read the post quickly missed Gallons and read liters and still thought 'thats high'

can you minimise the deadspace by adding an internal dip tube and or simply tipping towards the drain port closer to the end of the draining of each vessel? - if 100 gallon brews ignore
But if brewing 5 gallons thats over 1/3rd the volume in deadspace???

fwiw my 100/80/100 setup aided with a lil tip forward at the end of each drain has a total deadspace less than 1% of postboil volume..


but in answer to your question Yes.. Add the deadspace volume to your total liquor volume, and if the deadspace represents upto 5% of the total volume i would leave the grain bill as is initially and estimate efficiency conservatively but if a more significant volume Yes add to the grain bill too


once you have a brew or 2 under your belt and have better experience based estimates of mash efficiency and boiler evaporation rate you can tune recipies to hit final volume and gravity targets, imho while running in the kit to work out how it all works together i would focus on the single target of final gravity, you will just end up with a bit more or less beer that way

[wushurichard]

Hi,

Thanks, that's really helpful. Just for clarity, increase total liquor vol. by 1.8 gal in the mash? or split between mash / sparge ?
My boiler is a brupacks one (27l volume) and mt MT is a converted cylindrical cooler (10 gal vol)
If i was to go again i would definitely not go for that boiler as the dead space is pretty silly.

If i were to poor it i would most likely get some back but it may make sense to siphon

[Fil]

Decide on adding the extra to the mash or sparge by judging the effect on the mash consistency, for example if a large void is sat below a false bottom add to the mash to account for said void otherwise add to the sparge volume. you want a good porridge consistency in the mash

the simplest method of reducing deadspace is to employ the siphon effect with the drain, an inner diptube attached to the drain to suck from the bottom of the vessel and a corresponding hose attachjed to the valve dropping below the pot bottom can allow you to drain close to the bottom even with a valve mounted higher up the pot wall,

I tip all my pots forward to minimise deadspace too.

[wally]

My 50 litre mash tun is bottom draining so I have zero dead space in that, however I purposely leave approximately 5 litres in the kettle to ensure I get clear wort to the fermenter.

In the scheme of things grain is fairly cheap and the brewing software does all the calculations. It's not a big deal for me.