9" Vs 12" Ss False Bottom

[Phrak]

(I feel like I'm on a posting rampage today!)

Can anyone enlighten me about the potential, perceived or real, differences between a 9" and a 12" Stainless False Bottom when used in a converted 50L keg?

The information I've found so far seems to indicate adequate extraction efficiency with the 9 inch-ers...

Any smart-arse who posts "duh, they're a different size!" will be shot

Cheers,
Tim

 

[Screwtop]

(I feel like I'm on a posting rampage today!)

Can anyone enlighten me about the potential, perceived or real, differences between a 9" and a 12" Stainless False Bottom when used in a converted 50L keg?

The information I've found so far seems to indicate adequate extraction efficiency with the 9 inch-ers...

Any smart-arse who posts "duh, they're a different size!" will be shot

Cheers,
Tim

Errr ahh - Shoot Me :lol:

 

[Effect]

I want a false bottom for my converted keg...will be going 9 inch - cheaper (I like cheaper)

I heard the 9" is better than the 12" somewhere though...


oh - are they easy to install??? just chuck em in and away they go?

 

[drtomc]

Okay, I don't know anything, but the bigger one has more surface area (nearly double about 450 sq in vs about 250 sq in), so with the same runoff per square inch, you'd get much faster lautering. Alternatively, it might mean you can lauter at the same rate but with much reduced risk of a stuck sparge.

YMMV - I've only done 1 AG, and that was BIAB, so really, I don't know anything.

T.

 

[Adamt]

Extraction efficiency with false bottoms is determined by runoff speed (as far as I can understand), and I think the difference in runoff speeds between the 9" and 12" would be minimal if any.

Edit: This is of course, assuming batch sparging.

 

[Bugglz]

I believe if you are bulk spargeing then there is no problem, but if fly spargeing then channeling can be an issue. Not sure tho...

 

[porky]

(I feel like I'm on a posting rampage today!)

Can anyone enlighten me about the potential, perceived or real, differences between a 9" and a 12" Stainless False Bottom when used in a converted 50L keg?

The information I've found so far seems to indicate adequate extraction efficiency with the 9 inch-ers...

Any smart-arse who posts "duh, they're a different size!" will be shot

Cheers,
Tim

Can you visualize the difference it would make if one were 1 inch in dia. and the other was 9 inches?
same idea, different ratio. bigger is better I think.

Cheers,
Bud

 

[Effect]

when he said converted keg I just thought he was going to use it in his keggle for boiling (not mashing)

 

[grw74]

I might be stating (what I think) is the obvious but 9" where designed for tooheys kegs and 12" for Carlton kegs. I run a 9"in a double carlton keg and haven't had any problems with run off. I'm of the opinion that a fast run-off isn't so good as you never get the efficiencies needed for brewing on a budget.

There's my 2 cents.

Cheers :icon_chickcheers:

 

[warrenlw63]

Have used both (in 50 litre S/S vessel). For batch sparging no difference at all.

Warren -

 

[porky]

I might be stating (what I think) is the obvious but 9" where designed for tooheys kegs and 12" for Carlton kegs. I run a 9"in a double carlton keg and haven't had any problems with run off. I'm of the opinion that a fast run-off isn't so good as you never get the efficiencies needed for brewing on a budget.

There's my 2 cents.

Cheers :icon_chickcheers:

I think the grain bed will control the run-off. Does in mine anyway. The larger size will help for a stuck sparge.
My mesh is much smaller than commercial false bottoms though. It is a fine as a braid.

Cheers,
Bud

 

[white.grant]

I might be stating (what I think) is the obvious but 9" where designed for tooheys kegs and 12" for Carlton kegs. I run a 9"in a double carlton keg and haven't had any problems with run off. I'm of the opinion that a fast run-off isn't so good as you never get the efficiencies needed for brewing on a budget.

There's my 2 cents.

Cheers :icon_chickcheers:

Yes, you need to have removed quite a lot of the top of the keg to get the bigger one in a tooheys or lion nathan keg. Either that or cut a slot.

cheers

grant

 

[Phrak]

when he said converted keg I just thought he was going to use it in his keggle for boiling (not mashing)

nah, either size would make a reasonable hop-screen in a keggle. My primary reason for the thread question was for use in the Mash Tun. :icon_cheers:

 

[Phrak]

I think the grain bed will control the run-off. Does in mine anyway. The larger size will help for a stuck sparge.
My mesh is much smaller than commercial false bottoms though. It is a fine as a braid.

Cheers,
Bud

Hmm, that's an intersting idea that could save me $50.

I presume that your star-shaped-structure is the actual top of the keg that you've removed?
Any old SS mesh will do? eg an el-cheapo SS sieve basket?

What'd you use to secure the mesh to the star? Looks like rivets?

 

[Phrak]

Yes, you need to have removed quite a lot of the top of the keg to get the bigger one in a tooheys or lion nathan keg. Either that or cut a slot.

cheers

grant

Size is not an issue for me - My current hole size is cut to fit a 30cm stock-pot lid.

To be honest though, I'm not particularly seeing a compelling argument for either size.

I guess what I was hoping for was a concensus of, "the bigger, the better" or "there's no difference, get the cheaper one".

Seems others are just as unsure as I am :huh:

Tim.

 

[Adamt]

Well Phrak, someone has actually used both and noticed no difference (wazza), and an insightful genius (in my humble opinion anyway ) also suggested there would be very little difference. Hence the only difference is the price so go for the cheaper 9" one.

 

[Phrak]

Well Phrak, someone has actually used both and noticed no difference (wazza), and an insightful genius (in my humble opinion anyway ) also suggested there would be very little difference. Hence the only difference is the price so go for the cheaper 9" one.

LOL, perhaps so :lol:
I'm leaning that way as well, to be honest.

Decisions, decisions...

 

[drtomc]

There's also the "good enough" argument. I know it's unfashionable, but if the 9" does a fine job, why not go for it, even though the 12" might possibly have a lower risk of stuck sparges for particularly awkward mashes.

Or if you're that way inclined, go the bling direction and buy the 12" so you can say "mine is bigger than yours". Well, since other people have a 12", "mine is at least as big as yours".

T.

 

[schooey]

Now I believe I read, or I was told once upon a long time ago, that ideally a false bottom should have as much free surface area outside it within the vessel it fits, as the false bottom covers in itself. As Backyard Brewer mentioned earlier, I believe this is why the two sizes were coined, one for the shorter, larger diameter sankey kegs, and the other for the taller, smaller diameter kegs.

The school of logic behind this theory, so I'm told, is to avoid the wort channeling down the sides of the keg to the outside of the FB, if it is too large in diameter for the vessel, rather than making it's way through the grainbed, to a smaller diameter FB. So in this case, if you have the smaller diameter keg, you can get the smaller, cheaper FB. It's a win win.

 

[Screwtop]

Have used both (in 50 litre S/S vessel). For batch sparging no difference at all.

Warren -

Thank god someone replied "from expereince". Tons of info re sparging on AHB, please do a search. "From experience" efficiency increases with a slow sparge, how a larger or smaller FB or manifold would affect this is beyond me. Channeling is more related to crush and how you treat the mash (stirring and drain speed) than the type of filtering device at the bottom of the tun. Jay uses a high temp PVC manifold, batch sparges and achieves +80% efficiency after a good slow sparge. Does the type of filter really matter, more to do with process IMO. Buy whatever size and type spins your wheels :lol:

Screwy