Constructing a mash tun

[Springer]

Hi all,

am in the process of constructing a mash tun for a gravity / herms brewery, 15 + gallons capacity. The pic shows the progress so far, dia is 450 mm and height to top of dished end is 150mm. The tun is one end that I cut from a big industrial vessel the other end will be the boiler, which is also under construction, but I think I know where I'm going with that, once I decide on gas or electric heating or both.
I Know its not shiney, the inside is, would be if someone had not painted it. It going to be well lagged, like I get sometimes, so the looks don't matter to me. :lol:

Also a quick pic of the insulation jacket, to keep the rock wool in order.

The question is what sort of strainer / false floor do I need ??
I have in mind to make a floor similar to a smaller one I made some time ago for my boiler, and then have a copper tube set up, below the floor, like the ones we do in picnic boxes.

Will this idea do the job and if so is aluminium ok or even polycarbonate, stainless is available , but is it needed, because it is so much harder to work.

Your thoughts would be appreciated.

 

[Vossy1]

Love the insulation jacket, very tidy :thumb:

Will this idea do the job and if so is aluminium ok or even polycarbonate, stainless is available , but is it needed, because it is so much harder to work.

Polycarbonate will be o.k as long as it's thick enough to withstand the grain bed being on it.
Aluminium, Personally I wouldn't use it. It doesn't like acidic solutions too much and at the very least you'll strip the oxidised layer of the alu every time you use it. As I said personal preference, it will do the job though.
Stainless....now you're talking

 

[Springer]

Thanks vossy,
Polycarbonate it is then. Recon I can scrounge a bit of 6mm or better 8mm or 10mm if I'm really lucky from a local sheet supplier with a scrap bin. Might have to oil the wheels with a beer sample
The plan is to support it in the middle with a securing bolt, that might be stainless :lol: , from the centre of the outlet. Don't want it going walkabouts when I get my big paddle in, with disastrous results later.
Progress has been made on the sparge arm, as per your direction. Not stainless unfortunately :lol: , but next best thing ..........copper. A piece of 22mm cross drilled in two places to take two 15mm arms. Had to resort to the vertical mill to do the drilling, ordinary drill bit made a real dogs dinner, ruined 50mm of 22mm copper pipe , . :lol:
Put a pic up tomorrow if the drilling gets done.
Here's a thing, might sound stupid but, are the holes in the sparge arm up or down. :?

 

[jamesb]

Here's a thing, might sound stupid but, are the holes in the sparge arm up or down. :?

Depends if you want it spinny or not.

If you're hovering it just above the grain bed in a fixed position, stick them down. If you want it to spin, there's a particular arangement of holes to use. See if you can find a close up picture of Phil's Sparge Arm and you'll see what I mean. It has a curvature of holes on the side towards a (I think) 45deg-ish offset. Repeated on the opposite face.

 

[Vossy1]

Sparge arms come in all shape and sizes, your imagination is the limit :)
I rest my sparge arm on the mash liquor surface. When I'm using my copper SA the holes are on the top like this

and I use a stainless verion of this
like this

One of the simplest sparge arms is one used our member Phil here, click on mash tun and scroll down :thumb:

 

[jamesb]

One of the simplest sparge arms is one used our member Phil here, click on mash tun and scroll down :thumb:

I have got to stop regularly looking at Phil's pages. Costs me a fortune in Kleenex.

 

[shaunsbrew]

i know what you mean james, phil has a lovely rack and cracking set of vessels :rofl:

 

[jamesb]

i know what you mean james, phil has a lovely rack and cracking set of vessels :rofl:

:shock:

 

[Vossy1]

:rofl:

 

[Phil]

i know what you mean james, phil has a lovely rack and cracking set of vessels :rofl:

Why, thank you young man :rofl:

/Phil.

 

[Phil]

The "H" manifold was originally my HERMS return manifold. I used to use a spinny sparge arm until that broke. Now I do indeed use the "H" manifold as my sparge arm.

There are loads of ways to sparge. I've seen people just lay a return tube on top of the mash. It wouldn't be my choice though as I think it creates too much surface motion potentially (ie not proven one way or the other) laying the foundation of HSA.

At the end of the day I believe that you need a way of getting sparge liquor onto the grain bed with the minimum of disturbance. How you do it is up to you but the "H" manifold works just fine and is simple to make.

/Phil.

 

[Springer]

Plenty of info there, thanks to all
Think I will continue with my 22mm vertical tube cross drilled at bottom for two 15mm pipes, with holes up or down doesn't seem to matter then. :)
Picked up some special rods for brazing copper without flux today. Will try it out on the tubes to see how it goes, as a fore runner to brazing up a heat exchanger. Was going to solder it up but fancy the brazing if it goes ok?
No pictures of the tubes tonight, just spent an hour and a half persuading an inch bsp tap up the outlet of my tun, cos the inner end was "mashed up" already. :x Deserve a beer and dinner

 

[Vossy1]

with holes up or down doesn't seem to matter then.

If you're resting the sparge arm/return manifold on the surface of the mash then you only want upwards facing holes, as any holes facing downwards may disturb the mash (unless the flow rate is absolutely minimal)
Naturally, if your sparge arm is supsended above the mash (ie, sprinkling liquor onto the mash) then bottom facing holes are ideal.

 

[Springer]

Downward facing holes for me, with a clamp set up arrangement, to adjust height, depending on mash volume, might not want to do the maximum always but can't imagine why not :)
Tried the brazing rods tonight, put em on with a small lead burning oxy/acetylene torch, they certainly flow well, maybe to well for gap filling. Maybe over come this when I get my act together and am not over concerned about ending up with copper splodge on the floor. :)
That pic of Phil's, crystal clear wort and repeatability, certainly hooked me on a herms set up. Bid on a Tatton pump on ebay tonight but was to mean, anyone out there buy it. ? I think I will have to bite the bullet and dig deep into my pocket, trouble is i have short arms :lol:
Vossy, I was thinking about my combi pump, I think it could either taint the beer, not be noticeable and fine, but kill me over an undetermined period. I can sort the first one, the second is ok but can't get the third out of my mind, except if I knew it was over 25years I'd give it a go. :lol:
I don't think the material will be food grade. Did some research and there's lots of info out there. I might resort to plan B, the dishwasher pump, that should be food grade should it not, or maybe plan C and try to make my arms grow. :lol:

 

[Vossy1]

I was thinking about my combi pump, I think it could either taint the beer, not be noticeable and fine, but kill me over an undetermined period. I can sort the first one, the second is ok but can't get the third out of my mind, except if I knew it was over 25years I'd give it a go.

:rofl:

 

[Springer]

Progress to date with the mash tun.

Don't know whether it was worth white but I extended the tap to be a bit neater and to prevent heat loss ? Used 22mm as I have had problems with my present picnic box set up with lose nasty small bore plastic tap, filters come loss. I plan to firmly fix filter in to this set up and not leave it flopping about. The vessel outlet needed bushing down anyway so I left it large. :)
ThinK I have definitely gone over kill on this, but these no an easy way out when you have 40 or 50 litres of mash stuck in there. :)

The supporting construction, that should hold it firm :lol:
Once rockwool was added a piece of 6mm ply was screwed to center blocks and around edge, to allow for any future maintenance !

 

[Vossy1]

Very tidy Springer and very well made

 

[Springer]

And there more !

Now the question............. Will this make a suitable false floor / filter, more holes could be added and rim spaced up a couple of mm to allow draining off at the bottom. (with the univeral brewers scaling object :)

Tescos under a fiver, it could go back as not fit for purpose, or make a nice extra present for Mrs. S. :lol:

S

 

[Vossy1]

Lovely joints there S
Ideally the mash tun fb wants to have holes no larger than 2mm in diameter to stop grains/bits of grain getting through.

 

[Springer]

I did think they might be a bit big, certainly more than 2mm, will go on to plan B............... Don't have a plan B yet :?
Apart from the way of the picnic hamper mash tun, copper pipe with saw cuts ?

S