MLT idea: Does space under grain bed matter?

[MonkeyWrench]

I'm sitting here thinking about a system I want to build and started thinking about a grant and run off speed etc.

So here's my idea:

If you raised your false bottom up say 1-2" off the bottom (I'll be using a converted keg), and installed your sight tube between the bottom and the FB, wouldn't the space under act like a grant because the pump could never actually pull directly on the grain bed compacting it. If you pulled more liquid out than the grain bed could flow, you would loose height in your sight tube and eventually suck air.

I realize having that much dead space could cause you to run a thinner mash because you need to increase the total volume in the MLT. I'm planning a HERMS system so I'd probably be running 1.5q/lb anyway, and I'm not sure whether I'll be no sparge, batch sparge, or fly sparge yet.

My other idea was not using a FB at all and cutting the bottom out of a smaller SS pot and welding in a FB screen. Said pot would fit snuggly inside of the MLT and act as a BIAB where the whole pot would be removed when done for easy cleaning. The same issue comes up about space under the FB and the effect it has on the mash.

What do you guys (and gals) think?

 

[audger]

wouldn't the space under act like a grant because the pump could never actually pull directly on the grain bed compacting it.

the space under the false bottom wouldnt be open to the outside, would it? or are you thinking the top of the sight glass would be open, and the bottom of it below the FB?

 

[MonkeyWrench]

the space under the false bottom wouldnt be open to the outside, would it? or are you thinking the top of the sight glass would be open, and the bottom of it below the FB?

Ya, the top of the sight glass would be open and the bottom below the FB, the sight glass would allow air to be pulled under the FB so there would never actually be an suction on the grain bed. I guess the same thing could happen if you hooked up a dip tube to your sight glass and that went under the FB. It wouldn't need to be elevated much at all.