The Kiwi Style _ False Bottom Screen Riser _Corn mash out

[Kiwi-lembic]

Ive been working away at an idea and thought id share this...in the hope it may help someone ..
after many corn cooking experiments i made it a goal to beat that corn clogging false bottom mash tuns and based on a bet that the guy bailed on:)
in this experiment i used flaked maize,it does behave a liitle better than cooked corn ,,but thought id start here
heres my idea , ive just finished a 50 liter test run and its worked pretty well ..
with a couple more tricks i feel i might of nailed that corn clogging false bottoms ..ill post more pics and test run results soon
first concept was simplicity in design ..increase the surface area of the screen and rise on up above where my tests showed me the liquid floats after the corn settles
secondly use my herms system i use for even mash out temps ..if failure struck i could reverse pump...pushing hot wort rising thru the grain and keeping the screens clearer ..we didnt get to that as all behaved pretty well
..its as rough as guts but i never spend too much time making things pretty till they have proved they will work (apart from on paper)
the article is about the diameter of a keg top its made from stainless mesh .copper tube with 1 mm cut off slits to take the mesh and hand stiched with stainless spp wire i had spare

[Kiwi-lembic]

so after my trial run on the screen riser ,i spent today in the shed doing some keyhole surgery and screen cam experiments to see what this thing is really doing
theres no doubt about it that maize or corn has a very fine powder that really can form a blocking barrier on any screen.
the first part of the drain goes great...it pours out ...as the liquid level approaches above the settled grains
As it hits the grain level she slows but with some thought i took the top off the riser (once the liquid was below the top of screen )
Lying on the screen at the bottom was very fine corn dust so i just scooped this off and away it went again .so the design warrants a removeable screen lid .
my mash tun has about an inch out pipe on it with a ball valve tap on it .
increasing th size of this to 2" would also eliminate any potential blockage.
I really feel ...fine swollen corn dust wants to choke anything like a wife gone wrong ,especialy at the bottom screen with the weight of the grain pushing down making it worse
Hence the idea lets make a tower that hasnt this pressure on it like the bottom screen ,increase the surface area of screen mesh by almost double and it could work. .
The old mash Tun has done over 100 succesful all grain beer mash outs and works great..its not my build i bought it and always waited the day to give her the big pretty up now maybe the time
Its 2 water cylinders ....one inside the other a drain from the inner and a drain for the outer shell holding our double boil water
it has 3.5 killowatts of power and boiled the maize just fine
i was thinking of glycoling it but to be honest the outer shell came in really handy yesterday to dump some temperature in my mash out method by fillin it with cold after the boil.
the other big plus of the screen riser is i can still drop my copper coil wort cooler down over the risers screen tube and eccelerate cooling the wort ready to throw in the other grains for mash temp

[Kiwi-lembic]

more of the process...The corn maize sight glass builder

[Kiwi-lembic]

many experiments with visuals where done .always helps me in design ..seeing ..thinking before we hit any copper
and a special Thankyou To the Dunder for all his amazing knowledge and kind help over the last 2 years

[Kiwi-lembic]

thats about it for now i have some more ideas that i believe will make this work to a treat .find it wise to run it a few times more then do the rebuild ..least waiste ...enjoy..take care ..Kiwi_ L
special thanks to Rubber Duck and Usage also ...who have been friendly and helpfull ..thankyou from the bottom of the world

[LWTCS]

That's a nice Wright up.
And with out knowing one way or the other,,,,,,seems like a really good tool

[Bushman]

I am with Larry, very simple visualization tools, I like the way you think!

[Kiwi-lembic]

Bushman and LW ,thankyou for your kind words ,
i started over 2 years ago just fiddlin around when time permits... with corn straight off the cob (dried).
Following Dunders and another 3 members great help ..
i experimented with small batches in a kind of backward method teaching myself that certain mash/cook methods have definate affects in converting the corns starches to sugars
Making small visual jars and watching what they did till fermentations end .
With my all grain beer i use pre malted grains as it is easier for me here in New Zealand and readily available .
understanding the concept of how roar corn behaves was a good place to start .
My grain supplier has only one flaiked maize supplier which is Bairds.
they state that it is fliaked rolled .steamed (pregelatanised )corn
so i got a sack and started fiddling with what they say (a pre-cooked corn that is rolled)
i loaded all its specs into my beersmith program and it calced out strike waters ,expected gravtys and so on

from 4 experiments and visuals i found the best method to suit this suppliers maize ..

reciepe was
Flaked maize 65 %
Ale Malt 20%
Wheat 15%

heres what worked out of the four tests in a basic fashion

preheat strike water and 73 c (you can add backset here also @ 25%)
adjust ph to 5.6
Add Flaked maize
and 5% malted wheat and Ale malt (enzymesin malt to help convert starches )
let steep at around 71 c for 1/2 an hour

raise temp to boil and boil for 1/2 an hour to rehydrate maize to a gelly mush state (so grains can get at starches for next step )

Let stand... cool back to mashing temperature to mash malted wheat and Ale malt @ 68c strike
Add malted wheat and Ale malt and mash out as normal holding 67 -70 c til
the iodine test clean and the expected gravity reached from beersmiths calculations

let cool to around 35 c and drain off the wort to fermentor
airate and biff in yeast

an interesting note just mashing the flaked maize didnt work... so with this maize it seams a little cooking does help... my pick is there all different dependant on where they are from and season ,steaming methods etc

there is some ways i can speed this up with wort cooling etc ..time soaking always seams to help breaking into that difficult to cook corn (bet ya many an ol moonshiner has made new swear words for that damn corn)

its a pretty crude explanation ,ill leave all the technical jargon out ..never stop learning ..its great

[rtalbigr]

That's some interesting work Kiwi. I've been doing some experiments with corn mashing myself over the past year but with cracked corn, using a step method of sorts so I'm not standing there stirrin all the time. At Dnders suggestion I have some more experimenting to do. I can see where your mash tun with it's riser screen could fit in, so sometime in the future I may be borrowing your ideas here.

Big R

[Kiwi-lembic]

another pic that may be of interest
the mash drained to the bottom of the screen for fermenting volume needed
left over night
sat with tap on to see how much the screen riser etc would drain ,the grain now fully collapsed slightly moist in hand as any grains are after mash
has approx 3 liters of liquid dripped out over night .(equals my mash tun dead space )
time to biff this lot on my vege garden or swap it for some free range eggs

[Kiwi-lembic]

In the shed again studying mesh grades etc .
ive tried to identify which is the biggest culprit in clogging up screens .

As the corn maize gelatanises and the mash progresses it seams to me to produce a very, very fine GOOOP ,this starts sticking itself to screens like poos to a blanket
in the pic on the left is what 98 % of the corn mash looks like...
on the right is the fine fine goop that was on the screen at the bottom of the riser ,It couldnt get thru

(looks like that stuff our mothers used to feed to our faces ,,mighta been to block ya nappies... less mess )

with the screen riser experiments i used a herms recirc pump liquid comes out the screens bum ,pumped back up the top of the mash and recircs even temp throughout the mash ..it has great advantage to me .

it worked pretty well till near the end but still did work (i only just have a trickle in my herms recirc so not to upset the grains to much )
the screen riser also allowed me to gently scrape the sides and gently stir the mash to keep temps even and all well mixed.
it also allowed me to keep the riser clearish ,very hard to do on the bottom screen with everthing pushing down ..
so heres my mark 2 improvement thoughts

i will dry this goop and find a mesh it can pass thru (just like the leg on nappies)
More open weve especially on the screen at the bottom of the riser .
with my herms recirc i can flog that goop as it comes through... still have it in the mash but contained ,just not attempting to choke any screen
this is where id take it next