Mash tun ideas

[MikeG]

There seem to be 96 pages of references to mash tun so I rejected the idea of browsing them all for an answer.

So, my question is:

Has anyone tried a thermostatically controlled heater in an FV surrounded with blankets/insulation?

...or even just an FV without a heater surrounded with blankets/insulation?

...or perhaps an electrim bin, used to heat the mash up in the first place, surrounded with blankets/insulation?

[HG]

I use an Electrim and have found that the thermostat can hold the temp fine without added insulation.

A FV vessel might be alright if the plastic isn't too thin, maybe a blanket or two would help on thinner fermenters.
It's worth experimenting if it's cheaper in FV.

[farmhousekeg]

I've only made on aG brew but mashed in a VERY old Boots FV which is quite thick. I wrapped it in a thick fleecy blanket and stood it on newspaper. It held amazingly well and after 3 hours it had only lost 2 or 3C!! The long mash time was simply due to a recipe and guidance I found online but it proved that the Boots FV was a goodun!

[MikeG]

That's brilliant, thanks all. I'm going to get an electrim.

...but why do people go to all the trouble of modifying cool boxes then?

[HG]

I found this on http://www.zen37219.zen.co.uk/boilers.htm

" Brupaks insulated mash tun, mashes up to 10 kg of grain, tip the hot grain in and it holds it at temperature without the need for reheating. This stops the formation of hot spots and burning that you can get when you mash in the boiling tub. "

10KG is also more than you could hold in a standard thermostatically controlled mash tun/boiler using a grain bag. Plus i suppose you you wouldn't need any more electricty once you've struck into the insulated mash tun.

[pantsmachine]

That's brilliant, thanks all. I'm going to get an electrim.

...but why do people go to all the trouble of modifying cool boxes then?

Good question, in my case a coolbox was cheap and took a 1/2 hour to modify(not including copper strainer but that came later and took an hour to make and fit). I don't have a thermostatically controlled heat source in it, just leave it on its own and it holds temperature well. Don't get me wrong the tun above on this post looks ver professional and appeals to the engineering side of me but i like simple just like me! Total outlay for my tun was about 25 quid, its 23ltr so big enough for 'normal' grain bills. Horses for courses my man.

[boingy]

Many years ago, when I did my first AG stuff I used my Bruheat boiler to mash (same idea as an electrim). The first problem you have is that you cannot have the grain loose in the water because it covers the heating element. In my experience, grain is a superb insulator so the element just cannot heat the mash properly. To solve this problem I used a grain bag so that the grain is held higher up in the boiler. This works better but it is stil hugely difficult to get a consistent and stable temperature across the whole mash. I would end up with the water underneath the grain being at about 77 degrees and the temperature at the top of the grains at about 62 degrees, even with regular stirring. Another problem is you ended up with a really stiff mash because much of the water was not in with the grain and this also made the temperature variations worse.

Having said all of that, I did make some great beer with that setup. I would typically mash for 3 hours, with enthusiastic stirring every 30 mins (more often at the start). Something I never tried was insulating the boiler. I guess if you insulate the boiler well enough, then raise the water to strike temperature then pitch in the grain you could probably turn off the element and use it just like the coolbox.

Discovering the coolbox masher was a revelation. Mashing is now consistent and quick and means you can use your boiler to heat up the sparge water whilst the mash is finishing off. If you have the budget, go for the coolbox.

[edit1now]

I went for two Electrims because I didn't know about the coolbox thing, and I got the second one as an HLT fairly soon after I'd moved to AG. Went to HERMS this spring. I now have the world's biggest pasta strainer as a false-bottom-and-sides which I use with a fitted grain bag. It works really well, but if I'd known about the coolbox MT a couple of years ago things would have gone in quite a different direction...

Preheating the mash liquor in the MT is a great convenience. There is a picture of my first attempt at Electrim bin insulation here, and the TC department has now made me a couple of bin jackets out of old camping mats. No pictures yet