Hole Size In False Bottoms

[peas_and_corn]

In an earlier thread, one person was upset because he drilled in the order of 2000 holes in his false bottom, all 1mm wide and was upset when he found they should be 1.5mm.

How crucial is the size of the holes in a false bottom?

If it is, is 1.5mm the ideal size?

Cheers,

Dave

 

[berapnopod]

I would guess the holes on my false bottom are more like 4 or 5 mm.

*giggle*

Berp.

 

[Jim_Levet]

Whether the perforation is holes or slits I was told by a "brewery consultant " that around 18% of the surface area of the false bottom should be open. As long as the grain doesn't pass through they are not to big, as long as the extract can pass through they are not too small.
James

 

[peas_and_corn]

Jim- interesting. 18% really isn't that much percentage wise, really.

So, would the holes in a stainless steel mesh be sufficient? They would be smaller than 1mm, would they be too small or would it work just as well?

 

[GMK]

sorry about this P7K - but this has been discussed in length in a previous old topic.

But 1.5mm holes are preferred - this is from Wes Smith at Maltcraft.

 

[Borret]

Mine are 2.5mm which is 0.1mm different to the 3/32 that the yankey perforated bottoms generally are. They also place the 3/32 holes on 5/32 centres which is alot of surface area. mine isn't that close.

It seems to work. For the record mine has 1848 holes

Brent

 

[///]

Also as a brewery consultant - 30% free space is suitable.

If you are mashing properly and floating the mash with a proper run-off 990 mins) then you will hav ebright worts from the first opening of the tap.

Scotty

 

[AndrewQLD]

Also as a brewery consultant - 30% free space is suitable.

If you are mashing properly and floating the mash with a proper run-off 990 mins) then you will hav ebright worts from the first opening of the tap.

Scotty

[post="113286"][/post]​

Scott,
Can you clarify your comments above. 990 mins has me a little confused and also 30% free space. Sorry if I sound dense, just not sure what you mean.

Cheers
Andrew

 

[///]

Sorry - 90 mins sparge at minimum. 30 % free space ie. a 3ml hole every centremeter.

If you mash in properly and float the bed, it does not matter the size of the holes - my MASTER has brewed on a system with 1cm holes. If you 'set' the mash bed, compress it and run off fast the obvious happens - grain gets sucked thru as do other detrious materials.

Running first worts slow and then increasing the speed is fine, from memory on the weekend i collected the first 100l of wort in 30 mins and then ran the mash to collection at 650l inn 1 hour 45mins total.

The efficiency on the system when from an expected of 75% to 87.

Scotty

 

[Steve Lacey]

990 mins has me a little confused and also 30% free space.

He just has a very big index finger and is a bit slow at getting that pinky to the shift key. As long as he stays a brewery consultant and not an English teacher... eh Scotty!?

 

[///]

Well I GAVE up Engrish teaching for Brewing - such a hard choice...

Steve - hows Nehon???? Seems there is some cheap Kit hanging round Japan and some fella's giving the Micro tree a bit of a shake. Nasty 2 vessel german stuff with undersized hot liquor tanks and bloody lager methodologies are going cheap ($AUD 120k!). I am hoping to be back in tokyo within the year on a US stop-over - i'd say you'de be keen to visit Kirin city... and my dodgey local liquor store in Ikebukuro?

I cant see why you could not get a nice 'obaasan' following going with some local beer?? I can ship you the hops for a bloody good beer. i found these pride of ringwood hops and they are great.... goldings root stock and all!!!

Ooops - back to the topic... ummm run slow, sweet malt-riote....

I dont have a deep voice or the right aliteration obviously to get malt into 'chariot'.....

Scotty

 

[kirem]

love it, my ftaher-in-law. KIAC signs that song all the time and it ***** me up the wall!

 

[Peter Wadey]

Mr Lacey wrote

He just has a very big index finger and is a bit slow at getting that pinky to the shift key. As long as he stays a brewery consultant and not an English teacher... eh Scotty!?

Nor maths teacher
I could be mistaken but a 3mm hole on 10mm centres gives an open area of
pi(1.5)(1.5)/(10 * sqrt(75) ) = approx 8%.

Drillling 2000 holes in anything is just plain nuts! Perf. metal in this instance is def. the go.

Rgds,
Peter (ex. B. Ed B. Math dropout, enjoying a role as a pedant)