Author Topic: repeated stuck mashes  (Read 3563 times)

Offline tschmidlin

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Re: repeated stuck mashes
« Reply #15 on: March 12, 2012, 09:05:30 PM »
My false bottom is held up by a bunch of stainless bolts/nuts in supporting spots.  If the false bottom is flexing, this could prevent that.

mine is just a basic dome like this: http://www.rebelbrewer.com/shoppingcart/products/12-Inch-Stainless-False-Bottom.html. do I need to add some feet to it?
Seeing the picture maybe not, but you can add a single one to the center, near elbow, to keep it off of the bottom.

I like the idea of putting wire in the hose to keep it open, or swapping to a more rigid hose.  if your high temp hose is anything like mine, it gets super flexible when it is hot.  Trying to run off the wort will probably create enough suction to suck it flat.
Tom Schmidlin

Offline jeffy

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Re: repeated stuck mashes
« Reply #16 on: March 13, 2012, 04:06:25 AM »
I had a false bottom like that once, only plastic.  I found that I had to hold it down with a long spoon or a weight to keep it securley on the bottom of the mash tun otherwise grain would get under it and render it ineffective.  Could that be what is happening to yours?
Jeff Gladish, Tampa (989.3, 175.1 Apparent Rennarian)
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Offline melferburque

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Re: repeated stuck mashes
« Reply #17 on: March 14, 2012, 07:25:01 AM »
I checked with the LHBS, they didn't have reinforced tubing in the right size. they did suggest I reinforce the silicone tubing I have with something, so I used a bit of stainless steel dip tube (I only needed a couple inches and had a scrap).  I'm sure it will reduce my flow a bit, but reduced flow is better than no flow.  I also made a minor adjustment on the false bottom, I noticed I could move the bottom nut a bit.  we'll see this weekend if it works. 

Offline richardt

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Re: repeated stuck mashes
« Reply #18 on: March 14, 2012, 07:51:36 AM »
All those ideas above are good ones.  I especially like the homebrewer's "intraluminal stents" that y'all  created for the hoses--brilliant, really.

It is also quite possible that, since you're using a round 10-gallon Igloo cooler, you are also seeing the effects of grain bed compaction (which you wouldn't see in a rectangular cooler).  Anytime the grain bed height approaches and exceeds its width, you're very likely going to see grain bed compaction which will significantly slow the lautering/sparging rate regardless of the false bottom used.

This is the reason I switched from the round 10-gallon Igloo (with 12-inch SS Bazooka Braid) to a 20.5-gallon rectangular Coleman Cooler.  Batch sparging is soo fast and easy now.  No stuck mashes, either.

Offline tschmidlin

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Re: repeated stuck mashes
« Reply #19 on: March 14, 2012, 09:06:34 AM »
we'll see this weekend if it works. 
If you have time, I'd try it with just hot water the first time and see what happens.  I think you should also see if you can get someone from your club to come over, you've got a bunch of smart guys there who can help you figure it out.
Tom Schmidlin

Offline melferburque

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Re: repeated stuck mashes
« Reply #20 on: March 14, 2012, 12:03:08 PM »


It is also quite possible that, since you're using a round 10-gallon Igloo cooler, you are also seeing the effects of grain bed compaction (which you wouldn't see in a rectangular cooler).  Anytime the grain bed height approaches and exceeds its width, you're very likely going to see grain bed compaction which will significantly slow the lautering/sparging rate regardless of the false bottom used.


the last batch I did was only 8.5# of grain, so it wasn't compaction on that stuck sparge.  definitely could be something from the larger batches I'd done previously tho.

Offline Slowbrew

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Re: repeated stuck mashes
« Reply #21 on: March 14, 2012, 02:01:32 PM »
I may be over simplifying but can you fit a piece of 1/2" copper pipe in there? If you have some laying around I mean.  You won't compress that.

Paul
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Offline richardt

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Re: repeated stuck mashes
« Reply #22 on: March 14, 2012, 02:09:10 PM »
OK.  Just be aware that the round 10-gallon Igloo is only 12 inches wide and 24 inches high. 
It'll still help you make beer--it will just take longer to do it.
I just think the rectangular ones are better suited for the homebrewer who wants flexibility with batch sizes (much easier to stir high-gravity mashes) and who doesn't have the time and patience to wait around with slow/stuck lauters/sparges.

A good rule of thumb for mash tuns and boil kettles is to have it be twice the size of your batch size--i.e., a 10 gallon batch size means using a 20-gallon Cooler (MLT) and a 20-gallon Boil Kettle (OK if they are a little bigger).  Practically speaking, it means less mess (stirring and boilovers) and more options (step infusions, thinner mashes,  transfering the vessel safely, etc.).  It is worth the slightly extra up-front expense compared to the smaller vessels.  You'll be wishing you had if you skimp.

Offline melferburque

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Re: repeated stuck mashes
« Reply #23 on: March 14, 2012, 02:38:25 PM »
I may be over simplifying but can you fit a piece of 1/2" copper pipe in there? If you have some laying around I mean.  You won't compress that.

Paul

that's what I ended up doing, I ran some stainless tubing inside the silicone.

Offline melferburque

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Re: repeated stuck mashes
« Reply #24 on: March 14, 2012, 02:43:55 PM »
OK.  Just be aware that the round 10-gallon Igloo is only 12 inches wide and 24 inches high. 
It'll still help you make beer--it will just take longer to do it.
I just think the rectangular ones are better suited for the homebrewer who wants flexibility with batch sizes (much easier to stir high-gravity mashes) and who doesn't have the time and patience to wait around with slow/stuck lauters/sparges.

A good rule of thumb for mash tuns and boil kettles is to have it be twice the size of your batch size--i.e., a 10 gallon batch size means using a 20-gallon Cooler (MLT) and a 20-gallon Boil Kettle (OK if they are a little bigger).  Practically speaking, it means less mess (stirring and boilovers) and more options (step infusions, thinner mashes,  transfering the vessel safely, etc.).  It is worth the slightly extra up-front expense compared to the smaller vessels.  You'll be wishing you had if you skimp.

I've never attempted anything larger than a five gallon batch, and don't have any intention to at this point.  if I ever needed to do a large grain bill type beer (more than 18#) I would simply borrow my buddy's identical kit and split the mash in two.  I rarely go over 15# on my grain bill, hasn't been an issue yet.

Offline fatguybrew

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Re: repeated stuck mashes
« Reply #25 on: March 14, 2012, 02:55:47 PM »
All great ideas. But is it possible that it is as simple as losing prime? With the hose maybe it is just softening to the point that it draws air somewhere. I had a cooler tun that loss prime all the time before I just took it all apart and rebuilt it. Maybe a small addition of rice hulls might help?

Offline melferburque

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Re: repeated stuck mashes
« Reply #26 on: March 14, 2012, 04:32:27 PM »
All great ideas. But is it possible that it is as simple as losing prime? With the hose maybe it is just softening to the point that it draws air somewhere. I had a cooler tun that loss prime all the time before I just took it all apart and rebuilt it. Maybe a small addition of rice hulls might help?

I've also given serious thought to adding rice hulls, especially when using rye.  what's the normal usage for them?  10% of total grist?