Cool box mash tun

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samnorfolk

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i brew up 5 gal brews, what size cool boxes do people use for theirs?

Cheers
 
I use a 28 litre cool box which will hold a maximum of around 8.5 kg of grain plus the mash water. That's more than enough for most 5 gallon batches.
 
I use a 28 litre cool box which will hold a maximum of around 8.5 kg of grain plus the mash water. That's more than enough for most 5 gallon batches.

Ok thanks, therefore if my grain bill is around 5-5.5kg plus mash water a 24 litre cool box would suffice?
 
Yes, as long as you don't want a very strong brew. I use a Tesco 24l coolbox with a typical gain bill of 5kg

Yeah most of my brews have the grain bill of 5kg as I'm not after super strong beer, just standard 4-5%
 
also did you have to add a tap to it?
No, but I think most people do.
Instead, I have a 12l plastic bucket with a tap fitted, and a filter behind the tap, which I use for sparging.
So, I bail out the cool box with a jug, pour it into the sparging bucket, and dribble hot water through the mash. This thread shows what I mean:

http://www.thehomebrewforum.co.uk/showthread.php?t=59805

It just seems so easy to me to fit a tap through the single skin of a plastic bucket, rather than faffing around trying to seal a double-wall flexible container.
 
No, but I think most people do.
Instead, I have a 12l plastic bucket with a tap fitted, and a filter behind the tap, which I use for sparging.
So, I bail out the cool box with a jug, pour it into the sparging bucket, and dribble hot water through the mash. This thread shows what I mean:

http://www.thehomebrewforum.co.uk/showthread.php?t=59805

It just seems so easy to me to fit a tap through the single skin of a plastic bucket, rather than faffing around trying to seal a double-wall flexible container.

seems a good idea to me, ive done similiar with my sparge bucket, except mine has tiny holes in the bottom and a circular mesh above that, slightly tilted which i put on top of my boiler. I have been using the family cool box which is a 45 litre one but think the mrs is too happy about it, might be better off getting a 24 litre one i think
 
contain the mash in a net grain bag ala biab then place a siphon tube under the bag and up the side, or connect to a manifold or FB if you go those ways.. keep the tube in the box during the mash and then siphon the liquor out from under the grain mass, also makes clean up a doddle too..

go for a bigger 28/30l box if you plan on batch sparging, if fly sparging you can get away with a smaller tun just sufficient to contain the grain bill + an inch or so headroom, remembering that the lids all ingress into the box volume too somewhat.

cheaper boxes have very poor insulation and benefit from a complete pull and repack with upgraded insulation.. also dont forget to insulate the hollow lid..

if fitting a valve/tap seal it to the inner skin alone using a bigger access hole in the outer shell ;)

enjoy..
 
contain the mash in a net grain bag ala biab then place a siphon tube under the bag and up the side, or connect to a manifold or FB if you go those ways.. keep the tube in the box during the mash and then siphon the liquor out from under the grain mass, also makes clean up a doddle too..

go for a bigger 28/30l box if you plan on batch sparging, if fly sparging you can get away with a smaller tun just sufficient to contain the grain bill + an inch or so headroom, remembering that the lids all ingress into the box volume too somewhat.

cheaper boxes have very poor insulation and benefit from a complete pull and repack with upgraded insulation.. also dont forget to insulate the hollow lid..

if fitting a valve/tap seal it to the inner skin alone using a bigger access hole in the outer shell ;)


enjoy..

Ok thanks, i was going to get one from tescos? anyone had any experiences with insulation problems?? What i was planning to do would be to mash in the cool box and then do the same as Hoppyland, after mash transfer it to another bucket which has tiny holes and a mesh on a tilt then i have used a watering can before with some holes covered and sparged it that way
 
I bought the 24 litre one from Tesco and the insulation is pretty poor. So I put some more foam insulation between the inner and outer skin. I also fitted a ball valve tap to the inner skin only, with a larger hole in the outer skin for it to pass through. I then put some more roofing insulation inside the lid as there is none in there. I used it like that and lost about 3 °c over 90 mins. So I then covered the outside with silver bubble wrap, which also makes it look nicer :thumb: I have also put a thermometer in the lid that protrudes in to the mash to monitor the temps. like this it lost 1 °c over 90 mins. In my last brewday I also put a sleeping bag around it and then put some towels on top and lost no heat at all.

Hope this helps

Jas

IMG_9722.jpg
 
The lid is normally the weakest point (ie no insulation) so I (and others on the forum) filled mine with vermiculite (perlite is also good) and it improved the temp stability significantly. The bigjas ' pimp my mashtun' approach is also a good option. Alternatively try one brew and measure the temp at the beginning (which you would do anyway) and end at various points in the mash (top , edge, mid) to see if you have a problem. I was losing most heat from the top to went the insulated lid route.
 
the 2 shells inner and outer of a cold box especially the cheaper types simply clip together so a fingernail and small screwdriver are all you need to gently crack the seal and separate. once apart you will probably find thin sheets of polystyrene (1970s style ceiling tiles) insulation with lots of air gaps.. simply wrapping with foil or mylar (£shop space blankets) and stuffing bublewrap in the gaps between sheets will improve the insulation no end, the lid too should be a similar 2 part clip together arrangement, some fill with expanding builders foam but that can be messy and result in an expanded lid, i pulled my old one appart and stuck squares of bubblewrapp in the cells, otheres have drilled the top and filled with vermiculite or perlite with a funnel ;)

spend real money on a coldbox like the coleman extreme range and the insulation will be form moulded to fit precisely..
 
My Mash tun is the most expensive part of my setup - I wanted one with a tap, but as already has been mentioned in the post I didn't fancy fitting one myself cutting through 2 walls etc.
Anyway this is what I use: http://www.the-home-brew-shop.co.uk/cgi-bin/sh000001.pl?WD=mash&PN=Deluxe_Insulated_Mash_Tun%2ehtml#SID=163

If I had bought all these parts separate and built it myself I would have saved myself about £10, so whilst £90 seems pretty expensive I'm really happy with it.

If I simply close the lid after adding the strike water I loose 1 degree over 60mins. If i throw a sleeping bag over it I loose nothing.
 
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