mash tun again

[WR400]

hi i am looking at building a mash tun using two different sized dustbins 50 ltr and 30 ltr ,the 30 ltr sitting inside the 50 with expanded foam to insulate and the same for the lid, the drain would be in the centre bottom of the 30 ltr bin, would a stainless steel mesh raised of the bottom work and what would the hole size of the mesh need to be, I have used these dustbins for fermenting kit brews with no ill effects so i think they should be ok for the mash tun

any thoughts

gary

[kenmc]

where is the expanded foam going to be? Outside the 50litre? Is it the stuff in a spray can? It may react with the plastic of the dustbin and melt it - there's some pretty nasty chemicals in the can...

[WR400]

the foam will be between the two a bit like a cool box or on the floor if it does melt the plastic( a bit of testing required me thinks).

[WR400]

just seen vossy's collapsed FB (nasty)supporting the Fb will have to be given some thought as well, didnt think about the weight must be a fair few kilos pressing down on it when in use

[WR400]

Hi DaaB
I agree with you on the food grade plastics, but its difficult to source here not big on home brewing except for wine of course and it could be a race between the nasty chemicals( farmers crop spraying or dustbin) or the liver giving out. i may go the cool box way


gary

[WR400]

thanks i will give them a try

[Vossy1]

Hi WR400

If your not using a pumped system an FB will probably be o.k with the weight of the mash, depending how it's supported.

If you are using a pump but it's not that powerful you'd probably also get away with it as the mash would hopefully stick before the fb collapsed

I have a very powerful pump and it just kept sucking ti'll the poor old FB could cope no more

[WR400]

Hi vossy
its not going to be a pumped system to start with, just trying to put together a system with what ive got lying about and not too much expense.
experimented with the expanding foam, not a great success although the foam expands it didnt fill all of the void between the two bins and also it did not set ( not exposed to air ). I use this foam a lot fitting windows etc but never tried to fill a large void before(asking for trouble). i will go with normal fiberglass insulation. Have made a counter flow chiller with some small bore copper and hose, the hlt is a stainless stell vessel about 85 ltr way too big to start but already had it. already have 3 plastic kegs and fermentation bins. starting to get it together

gary

[Vossy1]

Sounds like your well on the way to a full set up and you won't need to upsize for a while

[RabMaxwell]

I used 2 parts foam insulation for my mash-tun mix both chemicals togeather then pour into the space.

[iowalad]

I know some homebrewers around here who have used expanding foam as insulation for the lid of their cool box (I remembered we aren't Americans).

Good luck.

[Belto]

where you are using expanded foam supprt the shape where you can so that you do not get deformation.
As per my efforts on the coolbox lid.
THe foam forced the lid apart ref: the location slots

[itmustbemagic]

I have tried this expanding foam insulating my mash tun/boiler. I have found it to be an excellent insulator. The trick is to spray the 'gap' with water then put in the foam. Then spray the fresh foam with spray water and the stuff keeps expanding. it does apply a fair a fair bit of pressure at it expands but I have been very pleased with the results. See my link for pictures of my kit.
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