Pending Stuck Sparge.

[timmi9191]

Recently upgraded mash tun and went from 30 cm to 40 cm false bottom.

I figured with increased area of draw for the pump I would grind a little finer.

Im currently on second step of the mash and its already sticking. Im having to stir and break the bed to let the pump draw.

Im considering throwing in a hand full or so of unground grain, any other suggestions?

 

[MastersBrewery]

Mash size? Tun dimentions? Grain mill and gap? Meathod from mash in? Mash in temp?

 

[timmi9191]

Mash size? Tun dimentions? Grain mill and gap? Meathod from mash in? Mash in temp?

33l, 9.5kg grain
45cm diameter,
keg king mill,
obviously too small - about .035 on the scale
mash in 60
having to stir during every rise to allow pump to recirc enough to get to the next step
recirc herms
66, 70 and mash out at 75.

currently at 70

 

[timmi9191]

Btw - have already re-set the mill back to its previous setting.

 

[razz]

Most likely the finer grind has done it timmi, what do you use to connect the falsie to the outlet? Copper tube, silicone?

 

[timmi9191]

silicone.

no doubt the finer grind is the culprit, but looking for a solution asap. Currently starting the sparge, flow is ok at the moment. fingers crossed

 

[razz]

The only problem with silicone, or other soft tube, is it may collapse under the grain weight and appear as a stuck spare. I guess it's what you have always been using so to fine a grind the culprit.
keep some rice hulls on hand for future brews maybe?

 

[nala]

I think Razz is on the money.
I suspect that your thoughts are bigger false bottom the greater the flow through the grain bed!
The fact is that the pump size is only as good as the perculation of the wort through the grain bed.
The fact that you have milled your grain finer and the fact that you are using silicone tube from the false bottom to the pump is why you have a stuck sparge.
I appreciate that you have to learn why these things happen,but,you appear to be on a path to try to improve mash efficiency...new larger false bottom trying to pump at an increased flow rate will give you these problems.
A small increase in efficiency amounts to the square root of nothing !
Go for a flow rate that is compatible with your system and avoid stuck mashes/sparges.
Remember the rate at which the wort flows through the grain bed without being pulled through by the pump is the correct flow rate.

 

[MastersBrewery]

As well as mill adjustment for future brews, when mashing in allow time for the grain to fully absorb the liquor (say 10 minutes) before starting to recirc, and start your recirc off slowly. Following these steps with a good crush should see you able to run with the pump nearly wide open.