That would defeat the purpose. Bobby's BIAB FB is designed to replace the FB's intended for un-bagged grains.
BIAB bag getting sucked down to false bottom
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OP
OP
Thanks for sending that! I have a few options to try out!
mwayne112
Well-Known Member
Much better to slowly open the pump valve over the course of ~10 minutes to prevent sealing the grain bed. Disagree a high flow rate is the issue, but rather a high flow rate too quickly. With a rotometer/flowmeter it is easy to consistently increase flow rate at a known rate.
If you thoroughly stir the mash grains instead of manipulating the brewbag and the flow is restored then it must be the new brewbag mesh size causing the issue in your setup. All things the same. Recently replaced mine and stayed with the 200 mesh size.
OP
OP
Alright, update on this issue...
I purchased the BIAB false bottom from Brew Hardware, like the one pictured here...
I purchased it without the legs because i was thinking I would do like what is shown in this picture and have my dip tube go through one of the holes. Didn't fully think that one through as my dip tube lines up smack dab in the middle where the support pieces meet.
So now I'm going to get some bolts to use as legs that will have the false bottom sit above my dip tube. I haven't fully done the math, but this will triple the space underneath the false bottom.
That said - What is/are the downfalls of having more space beneath the false bottom?
I purchased the BIAB false bottom from Brew Hardware, like the one pictured here...
I purchased it without the legs because i was thinking I would do like what is shown in this picture and have my dip tube go through one of the holes. Didn't fully think that one through as my dip tube lines up smack dab in the middle where the support pieces meet.
So now I'm going to get some bolts to use as legs that will have the false bottom sit above my dip tube. I haven't fully done the math, but this will triple the space underneath the false bottom.
That said - What is/are the downfalls of having more space beneath the false bottom?
Without recirculating that water under the false bottom is outside the mash. With recirculating the pores of the bag clog unless you mill more coarsely.
What's shown in the picture? Looks like the dip tube is just in the right place. Or something I'm missing perhaps?
Is that a compression nut on the diptube, which screws onto a (close) nipple? If so, and it's a little too long, maybe you can shorten the diptube a tad?
BTW, I would keep that dead space as small as possible.
OP
OP
That's a picture of someone else's that they posted earlier in this thread. That's not mine. My dip tube goes right to the center of the "X" on the support pieces. Short of drilling a hole through the supports (which isn't a bad idea...), I can't get my dip tube in there. My system is the spike system with all tri clamps so there's no adjusting the length of the dip tube. It's all one piece. So my option is either drill a hole in the center of the "X" in the false bottom or buy legs for the false bottom and it will sit about 3" off of the bottom of the MT.
I did just get a mill so I can set my gap to what I need! My system recirculates so not an issue there.
Other than the clogging, no other issues to worry about?
Sorry, I didn't realize the picture was from another post.
Drilling a 1/2" hole through the middle of the cross supports will certainly kill its function.
Is that false bottom made by Bobby? If so, maybe he can weld you one with one of the cross members at an offset, giving your diptube the needed space. That support cross doesn't have to be exactly centered to do its job. If in doubt, a double strip, one on each side of the diptube, would make it even stronger.
Are you saying there's a tri-clamp fitting on the inside of the kettle attaching to the diptube?
Are these
I think I would have one leg in the center cross, at minimum. And in your case, under the off-center cross if you can get one.
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How are you heating the kettle? Reason I ask is because the bag can clog, the pump will either create a powerful vacuum that can damage the pot and fb, or if it sucks air down there you might get scorching.
I had the first issue, using that exact fb with 3" bolts for legs. It didn't collapse the false bottom but the pressure forced the legs down so hard it dimpled the bottom of my brew kettle. Dangerous accident waiting to happen, I barely caught it in time.
OP
OP
Sorry, I didn't realize the picture was from another post.
Drilling a 1/2" hole through the middle of the cross supports will certainly kill its function.
Is that false bottom made by Bobby? If so, maybe he can weld you one with one of the cross members at an offset, giving your diptube the needed space. That support cross doesn't have to be exactly centered to do its job. If in doubt, a double strip, one on each side of the diptube, would make it even stronger.
Are you saying there's a tri-clamp fitting on the inside of the kettle attaching to the diptube?
Are these double bottoms supposed to be used without any legs? How big is that span?
I think I would have one leg in the center cross, at minimum. And in your case, under the off-center cross if you can get one.
After looking at a picture of the false bottom, your right, there's a threaded hole for a leg right in the middle of the "X" so drilling a hole there is not an option.
Yes, it's from Bobby. I wonder if he'd let me return this one and order one like that..? It's worth a question I guess.
No, there is not a tri clamp inside. Here's a picture of the Spike MT and dip tube I have. The TC ferrule on the dip tube is welded so all I was saying is I cannot adjust how far into the kettle the dip tube reaches.
Not sure what you mean by a double bottom? The Spike MT has a lip on the inside of the kettle for the FB to rest on. It's either 3/8" or 1/2" off the very bottom of the kettle and that's what I was going to have this new FB from Bobby rest on, until I discovered the issue with the dip tube.
OP
OP
It's a HERMS system so it's recirculating through the coil in the HLT.
I have yet to have the bag clog so I'm not terribly worried about that. But I will keep that in mind as a concern. I dont' believe there's a scorching risk because there's no element there....
Interesting about the legs dimpling the bottom of your kettle!! That's no good... Not entirely sure about the way around that.
Thanks, that's a whole different situation than I imagined. Better and much more elegant too.
I meant false bottom.
1/2" space under the false bottom ought to be enough to keep the recirc loop primed, but you need to keep a close eye (ear) on it. It depends on the keen balance between wort drainage from the bag and removal by the pump. If you were to raise the false bottom to 1-1.5 inch (now being placed above the dip tube) it may be a bit easier recirculation wise. But you must recirculate in that case!
Just thought about this, again.
Both cross members on that false bottom would need to be relocated. If doubled up, they'd leave a nice opening in the center for the diptube to peek through.
The "bottom" of the diptube is cut under an angle, right? So it can't suck up against the bottom of the kettle.
You could effectively shorten the dip tube by adding a short spool and second clamp between the dip tube flange and the kettle flange.
OP
OP
This is why I love this forum. You guys are some smart fellers! Brilliant!
Let's talk that though...
That would then mean the dip tube would not be in the center of the kettle anymore. As far as I can tell, there's no concave feature to the bottom of the kettle to ensure liquid flows to the center. That said, any issues with having a dip tube that's not in the center of the kettle?
Nope, I like it actually being closer to or along the sidewall, so I can tilt the kettle to get the last quart or 2 of wort out, and easier.
After the boil, the center of the kettle is also the center of your whirlpool heap, keep that in mind.
What size TC fittings are those? Looks like 1.5"? I have a bunch of Dernord brand TC hardware I bought on Amazon. Great quality and really good pricing. You'll need 1 spool, 1 clamp, and one gasket.
You could also grab that same diptube that is meant for the next smaller kettle (I'm guessing 10G) and that will be about 2" closer to the drain. It's not incredibly important to pull from the center and that would be close enough.
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