Willow 55 Litre Esky

[therook]

G'day Brewers,

Is anybody else out there using a 55 litre Willow Esky as a mash Tun?

I am using one and are loosing about 3 - 4 c over a 60 - 90 minute mash ( only done 5 AG )

The finished beers still taste great though.

I normally sit the Esky on my work bench wrapped in a sleeping bag, yesterday i also added a piece of polystyrene inside the M.T sitting on top of the mash to see it it would help , but still lost 3 degrees over 75 minutes......it probably didn't help with it being -5 outside at 7:00am

I am seriously thinking of going to a stainless or ally pot as a M.T unless someone has some ideas.

Rook

 

[Thirsty Boy]

Why change to the stainless/ally?? I can only imagine that they would lose heat even faster.

I assume it would be so you could add some direct heat if the mash cools down, which you could also do with your Esky by just stirring in some boiling water.

Keeping an electric kettle next to your mash tun "might" solve your problem and save you the trouble of changing mash tuns etc

Not that I'm knocking a pot as a mashtun, just suggesting a solution that might be easier.

 

[Fents]

Rook i was discussing this with Peels and Wardhog yesterday over a couple...Peels use's a 50 Lt Stainless keg for his mash and reckons he lose's 3-4 c over an hour..

Ward use's an esky and reckons he lose's 1c over and hour...

I use a 25lt Pail bucket wrapped in camping mat and lose maybe .5c over an hour even in 5c weather outside (not minus 5 tho!)

I will be upgrading soon but dont know which way to go either - Keg or Esky? If its an Esky i'll still wrap it in camping mat and put some extra insulation in the lid...If i go the keg its gonna have an empty 25kg grain bag wrapped around it, then camping mat, then somthing else on the lid too....

Im in two minds, but the 50lt keg wins i reckon A) because it looks good with two others on a three tier swetup and B) because i've seen 12kg's of grain mashed in a keg no worries...

 

[therook]

Why change to the stainless/ally?? I can only imagine that they would lose heat even faster.

I assume it would be so you could add some direct heat if the mash cools down, which you could also do with your Esky by just stirring in some boiling water.

Keeping an electric kettle next to your mash tun "might" solve your problem and save you the trouble of changing mash tuns etc

Not that I'm knocking a pot as a mashtun, just suggesting a solution that might be easier.

Thirsty, the only reason i would change to a pot is i have spoken to a couple of blokes on here who don't loose more than 1c over 90 minutes with a well insulated pot.

I thought the added polystyrene would have done the trick...

Rook

 

[DarkFaerytale]

i use a 55L willow Rook and used to have heaps of trouble with it as well. brewing yesterday with it tho and i forgot to insulate but only lost 2C in both my 60 and 90 min mash's all i have is a large hunk of foam on top and i make sure i heat it up befor the mash with about 2 ltr's of boiling water poured over the top of the foam then let it sit for at least 10 mins befor emptying and adding water and grain

-Phill

 

[Thirsty Boy]

Thirsty, the only reason i would change to a pot is i have spoken to a couple of blokes on here who don't loose more than 1c over 90 minutes with a well insulated pot.

I thought the added polystyrene would have done the trick...

Rook

Yeah, I failed to take into account that of course it would be insulated. Still, I think that most people are getting roughly equal performance out of their eski. 0.5 - maybe 2 degrees over a standard mash. Thats what I get with the absolute cheapest shittiest eski I could find in Dimmeys.

Dunno, kegs/pots ARE nice and shiney and you can add direct heat to them in a pinch. Maybe you could give the boiling water additions a try just to hold you over while you make up your mind.

Mind you, minus 5 degrees is pretty bloody cold. Maybe the polystyrene will do the job when temps are a bit more reasonable.

 

[SpillsMostOfIt]

I lose a lot of heat from my big aluminium pot, but that could be because of the size - 75litres. I wrap it in a couple of layers of cardboard, then a camping mat and put a towel over the lid.

 

[DarkFaerytale]

perhaps a thicker mash would hold temperature better too? i mash at 2.5L per kg

-Phill

 

[animal_man]

I use a 'thermos' esky. I kid you not, last time my mash stayed at the 67 deg i started it at. But that thing holds the heat so well, touching the outside of the esky it still feels normal room temperature.

 

[SpillsMostOfIt]

perhaps a thicker mash would hold temperature better too? i mash at 2.5L per kg

-Phill

In this house, we obey the laws of thermodynamics!

I would argue:

More water = greater thermal mass = smaller percentage loss of heat = more stable temperature (for a given sized pot/tun).

Leading to:

Find a way to mash at local swimming pool or Port Philip Bay temperatures...

 

[Keifer]

I use a 55l rectangular esky with no insulation and loose about 4-5-6c over 90min. Temp only drops when i open the lid to have a stir as all the steam gets out, i usually just add some boiling water each time i stir it. Thats from memory, havn't been brewing for a while now aside from a kit here n there.

I can't see you NOT losing temp if you take the lid off to stir, reducing the space above with foam or whatever may solve that, im not sure never done it. Maybe leave it alone for the mash, or find someway to stir through the lid.

 

[DarkFaerytale]

In this house, we obey the laws of thermodynamics!

I would argue:

More water = greater thermal mass = smaller percentage loss of heat = more stable temperature (for a given sized pot/tun).

Leading to:

Find a way to mash at local swimming pool or Port Philip Bay temperatures...

i'm not gonna argue with ya, i always loose when i'm involved in one of those

i am gonna do a test tho!

-Phill

 

[geoffi]

I use one. I always warm it up beforehand with a few litres of boiling water. I certainly don't get temp loss like you site. Maybe 2c. Of course that also depends on the weather, as I brew outside.

The other thing is that if you're using well modified malt (and who isn't these days) the conversion should be complete well inside the our anyway.

If in doubt, chuck in a couple of litres of boiling water after 20 mins or so and give it a stir.

BTW. I have been told by someone who does this for a living (not in an esky) that a relatively shallow grain bed is a good thing, so the larger esky gets the tick on that score.

 

[matti]

G'day Phil, Geoffi and Rook and the rest of the big happy family of 55L rectangular eskies.

DFT, what is the foam "thingy" you are heating up prior to to adding grain and water?

I was thinking of using a foam esky lid just inside the willow esky.
Sticking the prope in through that and using hot water from kettle for
any corrections.

The only problem I can foresee, is the flimsy material the foam lid is made of.

I am thinking of a step mash so I will have to remove the foam lid every time I stir.

As for you ROOK, I think if you feel the need to step up its $$$.
You could work out the thermal mass and calculate the amount of water at 95C to add every twenty minutes.

**Boil Volume =[(Desired Change in Temperature) X (Volume Mash + Addition)] / [(Temperature of addition (i.e.95)) - (Temperature of the Mash)]

Calculation in Step Mash Theory thread from MHB

matti the Swede stralian

 

[agraham]

Hey Rook, i use a willow 55 liter with a long braided hose. I found that filling the lide with the expanda foam stuff helped reduce the heat loss by a couple of degrees for a 90 min mash. I would still wrap it in a blanket as well though.

 

[DarkFaerytale]

DFT, what is the foam "thingy" you are heating up prior to to adding grain and water?

don't you hate it when you type out a message then loose it

anyway it's basically just a big arse block of foam that i found at work (at least i think thats where i got it from), it fits the esky perfectly and is about 15cm thick

-Phill

 

[bugwan]

Hey Rook, I've found pre-heating the mash tun with a bit of boiling water (under a litre and then put the lid on) helps reduce the initial temp drop. Although it won't do much about losing temps over the mash period.

I only use a 36ltr esky (Nylex), so temps are pretty good through the mash. I put a piece of polystyrene over the grain to reduce the headspace too.

The other thing you could look at is spraying expanding foam into the lid and walls, as Batz mentioned once, but it depends on your existing insulation I'd imagine.

Pic of polystyrene on mash, with classy cable-tie handle

 

[geoffi]

Hey Rook, i use a willow 55 liter with a long braided hose. I found that filling the lide with the expanda foam stuff helped reduce the heat loss by a couple of degrees for a 90 min mash. I would still wrap it in a blanket as well though.

I knew there was a reason I kept all those foamboard offcuts from our under-floor insulation. A false-lid inside my 55L should keep temps pretty much rock-steady.

 

[samhighley]

Is this the Willow 55 litre that others are using?

There seems to be a more upmarket model with wheels, but this one looks the goods to me.

 

[Fents]

looks identical to mine except without the wheels like you say. oh and just a tip when your mashing in it, it really only holds 48L's, i found out the messy way.