Cool Box vs False Bottom FV

[arturobandini]

Hello,

When I first started planning my AG Brewery I was set on using a CoolBox Mash Tun due to it already being insulated and just a copper manifold away from being a full on Mash Tun. However, after more research the false bottom FV is throwing up more options and it looks like a cheaper solution even factoring in gaffer taping campint mats around it.

I've also read that the insulation properties of a CoolBox aren't actually that great and a few fleeces/duvets are needed anyway.

I know most people will use either one or the other so what are the pros and cons of your Mash Tuns?

[bramswell]

I use a FV with a mash and sparge bag and it works great, i also had thought of going the cool box route but have decided not to waste my money as th FV with sleeping bag is so good at the job, but i might add a false bottom, just to make clean up easier.

here's mine

[tubby_shaw]

I agree wholeheartedly with Chris and that's why I followed his design
I used to use a mash and sparge bag but it was always a PITA to clean.
It may not look as "cool" as a picnic cooler but it has never let me down
Here's the thread on building and using mine
viewtopic.php?t=2409

[Parva]

Just to offer an alternative opinion, the H&G supplied mash tun (a 30l Thermos cool box) serves me proud. With a couple of cushions on the lid (the only uninsulated bit of the kit) I drop no more than 1c over a 90 minute mash. The downside is that for making hefty beers and batch-sparging you are going to struggle with a 10G brew but it's certainly possible if you intend to fly-sparge.

[arturobandini]

What size grain bills can you get in those 25 litre fv's if you're intending to batch sparge? More than a standard hop and grape/brupaks thermos mash tun?

[Parva]

I aim for around 5%ABV 23l brews batch-sparged with my H&G Thermos mash tun and it's very easily produced with 5Kg - 5.5Kg of grain total. I suspect that I could get upto 7% brews for a 23l batch or drop down to 4%ABV and just about manage a 10G brew. If you're only looking at producing 40 pint batches then you can't go wrong with the coolbox. If you're thinking about doubling that up it is possible at a lower ABV rate or by fly-sparging. It works well for me. Or alternatively, do a double mash (as I have done recently) then just boil it up as one.

[adm]

In my experience, you can get a maximum of 10kg of grain in the H&G coolbox mash tun....but certainly no more!

[chrb]

I made a zapap lauter tun - advantage being that it's very cheap, total cost around £3 for 2 plastic buckets. Drill a hole in the bottom of one, stick some syphon tube through it, drill lots of small holes in the other, and it's done. It's basically a false bottom for the very lazy. For the mash I put a plastic bucket in a sleeping bag inside a cardboard box. Didn't pay anything for those, and I still use the bag for camping I've done 9.5kg of grain before (recipe) - buckets in sleeping bag, pour in to zapap, drain off, top up again with sparge water, stir, drain, empty grain, repeat. It's a bit of juggling and I'm a bit envious of those of you who just dump into a single vessel, wait and open a tap, but hey, it works fine and sparge/drain takes about 2 minutes. I get ~70% efficiency (I did experiment with a bowl over the top of the lot with more holes in it which I would fill with hot water to create a shower for sparging, but it took ten times longer than batch sparging and was more hassle than it was worth). Did I mention the mash/sparge setup cost £3?

I'm thinking about getting a couple of big polypropylene bins (£10 from Homebase), adding kettle element, and doing the whole mash, boil, ferment in a single bin. They look about 80 litres volume. I already made a boiler from a bucket and Argos kettle element, cheap total cost £6, it works but is really too small - 15 litres, thin plastic, boil is crazy, keep adding wort as it boils off and you can do a batch. But really too small... The Homebase bucket is big, thick polypropylene, looks great but maybe not food grade - not sure if it matters really...

Photos from my first ever brewing attempt, I actually just used the brewpot to mash here...

[farmhousekeg]

For what its worth (cos I am new to AG), I converted an old Boots 25 litre FV into a false bottom MT a la DaaBs design already mentiond by Chris. I insulated it with an old camping mat. The most expensive part was the roll of Gaffer Tape from B&Q and I estimate my total outlay was under £10 (I already had a spare FV, a camping mat and an old picnic plate!)

After a bit of modification of the brass tank connector the deadspace in the false bottom is 200 mls and on my first attempt last weekend the tun lost less than 1 degree C over 90 minutes without the aid of sleeping bags. I had a grain bill of 5.25 kg and was able to sparge that in 2 batches with a wee bit of room to spare. Although I've never used anything else, I'd happily recommend the DaaBs false bottom MT.

[sparky Paul]

For what its worth (cos I am new to AG), I converted an old Boots 25 litre FV into a false bottom MT a la DaaBs design already mentiond by Chris. I insulated it with an old camping mat. The most expensive part was the roll of Gaffer Tape from B&Q and I estimate my total outlay was under £10 (I already had a spare FV, a camping mat and an old picnic plate!)

After a bit of modification of the brass tank connector the deadspace in the false bottom is 200 mls and on my first attempt last weekend the tun lost less than 1 degree C over 90 minutes without the aid of sleeping bags. I had a grain bill of 5.25 kg and was able to sparge that in 2 batches with a wee bit of room to spare. Although I've never used anything else, I'd happily recommend the DaaBs false bottom MT.

Sounds great... I'm convinced.

Just need to find some cheap camping mats. I assume you need the really thick ones?

PS Chris is 'DaaB', by they way.

[farmhousekeg]

PS Chris is 'DaaB', by they way.

Ah ha, I thought as much! Now he's well and truly "outed"

[sparky Paul]

The one you see in my picture has 3 layers of 8mm mats wrapped round. As long as it is preheated it will hold a constant indicated temperature for well over 90 mins.

Ahh... I see.

I've seen lots of 8mm ones, but the thicker ones are harder to come by. I would think that the layering help with insulation properties too.

[farmhousekeg]

The one you see in my picture has 3 layers of 8mm mats wrapped round. As long as it is preheated it will hold a constant indicated temperature for well over 90 mins.

Ahh... I see.

I've seen lots of 8mm ones, but the thicker ones are harder to come by. I would think that the layering help with insulation properties too.

Chris has 3 times the insulation I have used - I have only 1 layer of 8mm. Never used mine outside in the workshop yet so perhaps I will add a layer when I use it out there. So far only used it in the kitchen with temperature of 20C+ in the house.

[sparky Paul]

Wasn't the fake beard and moustache convincing enough then ?

Many of the new internees don't know of your mysterious past.

They were the cheapest ones I could find in my local camping shop http://www.leisurefayre.com/ (where I used to be a 'Saturday boy' when I was still in short trousers )

I'll have to have a hunt round. I know many have found them in Poundshops and the like, but we haven't got any round here.

[sparky Paul]

(I was young and needed the money )

They all say that.