False Bottom For Mash Vessel

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Boots

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I was just having a sniff around in the Menzel Plastics across the road and found a possible false floor for a mash vessel.

I've been looking for something which would allow me to use my esky with minimum modifications, and may have just found it.

Oyster mesh is what they (perhaps obviously) use in the oyster farms; it provides a base for the growing oysters to sit on while still allowing for water flow. It comes in a few sizes, I've grabbed a sample of the one with 1.6mm holes.

One side is completely smooth and the other has raised ridges running vertically and horizontally (think somthing like shadecloth). It's made from black HDPE, food grade, rated to 60 - 70 deg, and according to the guys in the shop, would be food safe for short periods at up to boiling temps. It is also quite rigid.

I'm going to give it a wash and test it in some hot water for an hour to see if it imparts any flavours.

I'm thinking that with a few spacers to keep it just above the floor, it should work ok. After the mash, pull it out, and you have a perfectly functioning esky.

I'll let you know how it goes.

Boots
 
sounds pretty good.

What is the price and thickness?

For the round coolers - should be able to bend it into a dome shape between 2 dinner plates or domes etc.
 
It's about $11 -$12 / mtr, but the roll is very wide, so I only needed a half metre and it way more than I'll need.

Thickness ..... bout 2mm
 
I will take the rest or some of it off your hands....

What is the smallest size that it goes to.

For your spacers - buy some ss bolts and nuts and use them.
 
I like the sound of this. Any chance of posting a picture?

FYI, Polyethylene is rated as resistant to beer at up to 60C but I have no data for higher temperatures. That is for piping systems, so at 60C it would still be able to convey the fluid wothout deformation etc, so i reckon that the PE should be good for mash temps up towards 80C


Dreamboat
 
I took some snaps, but don't have a web site to link the pics to. How do you guys get piccies happenigng? do you use the gallery?
 
No point asking me, I have yet to post a pic, but someone please shed light on this so i can have a shot in the future also...

dreamboat
 
Ok Pic1. Excuse the terrible digital photography.

Oyster1.jpg
 
There's a file attachment option as part of the reply. Just browse to the graphic & select it. Make sure it's on the local machine though - it doesn't seem to like attaching files that are on network drives.
 
This size piece cost me just under $6. around 900 x 500

Oyster2.jpg
 
And a very bad close up to (try) and show the ridging on one side.

Sorry for the bad shots, i looked pretty stupid playing with this stuff in the office :blink:

Oyster3.jpg
 
Looks pretty good to me - maybe a bit flexible, but it is easy to support it on a stiffer wire mesh or similar. THe important bit is that it looks like it would retain the grain well.


dreamboat
 
I found a website in the US that deals in SS mesh - not that I want to spend a heap on postage, but it does give you an idea of how fine a mesh you can get nowadays. The link is here.......
The only problem is weight. How is 5kg of grain gonna go on the mesh, even with bolts propping it up? According to the SS mesh on that website, they quote 1.5kg per square metre for size 32 Mesh screens with 0.5mm openings...You'd need a $hitload of bolts to hold that up in a 10 Gallon mashtun :D

Is your oyster mesh firmer than that, Boots??? It certainly looks tougher than the flimsy fly screen type stuff that is flogged elsewhere...
Cheers,
TL
 
Hmmm, hard to say whether the oyster mesh would be more rigid than the SS mesh. It seems to have a closer weave than the metal mesh.

While it is quite rigid, I have no doubt that there will be some sagging, but I figured, as long as there are "channels" to allow liquid flow it should be fine. After all, manifolds only rely on small areas lik that .....

I reckon I'll get away with 5 supporting bolts. One at each corner and one in the centre.

Other options I could go if that doesn't work is to double it up, or even make a bazooka with it that runs the entire length of the esky.

I won't be trialling it for at least a couple of weeks, as I'm flat out at the mo'
 
Hi Guys,

A copper 19mm manifold will be easier to construct much more durable and give as good a performance for extraction. I'm happy to help any Adelaide All Grainers build a better "mouse trap" if they need any help.

The false bottom needs to be firmly in place and rigid to avoid grain crushing it or getting underneath and into the dead space.

Steve
 
Steve has a point there - the rigidity is going to hurt you in the long run if you're always having to prop the screen up - and as for chanelling, well that 's a no-no based on what I've read.
Just to drift a bit OT, I am thinking of using a Phils Phalse bottom in the Rubbermaid, but I hear that they float? I'm not too sure how much floating the plastic false bottom's gonna do with 5kg of grains on it - perhaps the floating occurs when the strike water is added before the grains - that wouldn't therefore apply if I underlet the grains...
Perhaps I should simply construct a copper manifold ring around the bottom of the Rubbermaid and hook it up to the nipple and be done with it!

Is 19mm copper easy to shape into a cylindrical mash tun?

Cheers,
TL
 
I had a go at setting this up in my esky the other weekend.

Result: I think it would be usable for a small area (ie. small round cooler etc), but for a large esky, it is too much stuffing around to cut it to the right size and trying to get it flat across the whole area, while maintaining enough support.

It's in the awkward (sp.?) range of stiffness and flexibility that makes it a bit too much hassle to warrant the effort (i'm not very patient, and have even less practical skills).

If you had a smaller area to use it in, I'd say it would be great (ie, like the phils phalse bottom thingy).

Oh well, only cost me $10 for the experiment.

After playing around with this, I think it would be just as easy to hacksaw some pipe.

Cheers
Boots
 
Hey Boots
You could have spent $10 on Marbles. No joke fill the bottom of esky with marbles throw in grain and water mash to temp. open tap, take out wort put back until clear walla all you do now is boil.
Refill
ALTBIER
 
That's an amazing idea Altbier ..... have you done this? Hmm ......
 
No. But there was a young fellow in QLD. that saw it in the states and was or is trying it.

Refill
ALTBIER
 
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