Grain getting through false bottom

[Mechengr]

Hey all! I've been a homebrewer for about 12 years, all-grain for 6. I've been a longtime user of this site but have never posted because I could usually find my answers! However, this time I have struggled to find a good answer for my specific problem.

This is a 5 gal batch setup using 8 gallon SS kettles for mashing, etc.

Anyway, last year I set up my own RIMS system so I could really control my mashing. I had great success last year for the most part, but this year I've had problems with both of my brews. The issue is that a lot of grain is getting by my false bottom and clogging up my RIMS system. There is nothing worse than having to take apart your pump while brewing!! I've uploaded a picture of my setup to give you an idea of what it looks like. There is definitely a small gap between my false bottom and my kettle but again, I didn't have many troubles last year. I typically run with my outlet valve wide open to ensure good circulation.

So my question; what should I be doing to minimize/eliminate the amount of grain going through the pump and heater jacket? The last two brews have been REALLY frustrating!

 

[day_trippr]

That pic isn't going to help anyone solve your issue.
Take a good picture of the inside of your mash tun with the false bottom in place so we can see what's up.
There are a couple of potential solutions but they're gap-size dependent...

Cheers!

 

[kh54s10]

If you have a gap between the kettle and the false bottom that is probably the issue. Is the gap different than before? Whatever, find what is different from previous brews and present ones and that will be the solution.

 

[homebrewer_99]

Make a seal. Take a length of tubing that is 1-2" longer than the circumference of the false bottom. Cut one long continuous slot down the length of the tubing. Insert the edge of the false bottom into the slot and cut to proper length.

 

[Mechengr]

Thanks all! I took some pics of the FB and my dip tube underneath. What type of tubing should I use? Am assuming silicone would be too flimsy and need something fairly rigid to stay attached to the FB.

 

[gnor]

Thanks all! I took some pics of the FB and my dip tube underneath. What type of tubing should I use? Am assuming silicone would be too flimsy and need something fairly rigid to stay attached to the FB.View attachment 577299 View attachment 577301 View attachment 577299 View attachment 577301 View attachment 577299 View attachment 577301 View attachment 577299 View attachment 577301

Use 1/2" silicon tubing, slice through the middle, and wrap your fb as a gasket.

 

[day_trippr]

That'd work. So would this https://www.brewershardware.com/Silicone-Tubing-1-4-ID-X-1-2-OD.html.
Still 1/8" wall thickness, just smaller diameter...

Cheers!

 

[Mechengr]

I'll give a shot!

One other note, I have my LHBS mill my grain for me, I wonder if they might be milling a bit finer than the past. Will see what happens on my next brew day.

Slainte!

 

[day_trippr]

Given the size of that gap I don't think crush is going to make much difference...

Cheers!

 

[kh54s10]

Given the size of that gap I don't think crush is going to make much difference...

Cheers!

Agreed. I wonder how you had any batches without a lot of grain getting by, with that gap. Especially if the FB was off center like in the picture.

 

[Mechengr]

I usually try to Center as best as possible before adding grain. But, I am now excited to see how clear a wort I can get after closing this gap!!

 

[homebrewer_99]

Thanks all! I took some pics of the FB and my dip tube underneath. What type of tubing should I use? Am assuming silicone would be too flimsy and need something fairly rigid to stay attached to the FB.

I'd recommend the same tubing you use on a racking cane...

 

[day_trippr]

I would not use vinyl tubing for any hot side application. Bad juju.
Besides, it's too hard to be compliant enough for a gasket. You want something much more pliable than vinyl.
Silicone tubing has been used to solve this problem countless times...

Cheers!

 

[homebrewer_99]

I would not use vinyl tubing for any hot side application. Bad juju.
Besides, it's too hard to be compliant enough for a gasket. You want something much more pliable than vinyl.
Silicone tubing has been used to solve this problem countless times...

Cheers!

Bad juju? Explain...why not vinyl?

It shouldn't be hard at all since it will be submerged under HOT WATER.

 

[kh54s10]

Bad juju? Explain...why not vinyl?

It shouldn't be hard at all since it will be submerged under HOT WATER.

I think the belief is that more bad things can leach out of vinyl than silicone.

Silicone is much more pliable than vinyl when cold so it would be a lot easier to use when installing the FB.

 

[day_trippr]

Right on all counts.
It'd be a mistake to use vinyl for this or any hot side application...

Cheers!

 

[homebrewer_99]

OK...thanks.

I have 2 false bottoms (different sizes) that I stopped using years ago. I prefer my SS bazooka screen (or whatever it's called).

 

[Mechengr]

Howday all, well I finally got around to brewing last weekend with the tubing in place and I would call it mixed results. I was only able to get tubing about halfway around the FB, otherwise it was way too tight to get into place. However, this did close 99% of the sidewall gap. Good news right?!
So I start mashing and turn my pump on for the RIMS and all looks good. Then after about 5 mins I start seeing a tun of grain going through the tubing... ARGH!! After fiddling with it for about 10 mins I was able to significantly reduce grain going through by adjusting the location of my output into the top of the mash tun and slowing the flow down with a ball valve. After I transferred all my wort to the boil pot, you can see the "erosion" I created with my low flow wort output in the picture below (pretty significant).
So.. is my crush too fine and I should be asking for a coarser crush, or should I continue to tweak my flow rates to avoid disturbing the grain bed too much? Or should I switch to a screen and be done with it?
Any other suggestions?

 

[homebrewer_99]

I think the belief is that more bad things can leach out of vinyl than silicone.

Silicone is much more pliable than vinyl when cold so it would be a lot easier to use when installing the FB.

Just a "belief"? Anything scientific to back it up? (Not being sarcastic...just curious...I REALLY would like to know).

 

[kh54s10]

Just a "belief"? Anything scientific to back it up? (Not being sarcastic...just curious...I REALLY would like to know).

Don't know for sure but that is most often cited... The the last part is most important. Vinyl would be very difficult to use for this purpose.

 

[homebrewer_99]

Don't know for sure but that is most often cited... The the last part is most important. Vinyl would be very difficult to use for this purpose.

I hear you, but I haven't seen anyone provide "proof" yet, as in a scientific study or a paper, article, something.

The 7 Deadly Sins aren't in the Bible and were made up by a monk who was exiled...yet people cite these as Biblical.

 

[gnor]

Back to OP, if the silicon tubing didn't work for you, I would suggest you to try a brew bag from brewinabag.com. With it, you can get away with finer milled grain.