Bag size to kettle size

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JamieGalea

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My Kettle is 35ltr in volume, height 36cm, diameter 36cm.
I am planning to start experimenting with partial mash but then would like to go to AG.
I generally do 23ltrs batches.

Is the kettle good enough if I had to switch to AG? And what Bag size would you recommend will work for both partial and AG ?

This is photo of kettle.
pentola_inox_con_rubinetto_sfera_35_litri_2.jpg
 
kettle is too small. You want a kettle 3x your batch size. That will cover any beer you will ever make. 2x batch size is OK for normal/medium gravity beers. If you ever want to make an "imperial" or other high gravity beer you will need 3 times the volume of your batch in your kettle if you do an all grain mash.

Decide if your kettle is big enough for your FUTURE plans. You can always make a smaller batch in a big kettle but you can't make a "big beer" (high gravity) in a small kettle.

Wilser will make you a custom bag for your kettle. Cost is no more than a regular "pre-made" bag. He is generous on his bag size. It will not be a "barely fits" bag. And the mesh size is nice and tight. A lot of other bags don't look too tight.
 
For us, U.S. brewers, 35 liters is 9.25 US gallons.

That's large enough for full volume boils of 5-5.5 gallon (23-25 liter) batches, leaving you also a bit of headroom.
But too small for full volume BIAB mashing. But you can get around it by incorporating a small sparge in a bucket, tub or beverage cooler, which also increases you mash/lauter efficiency.

For comparison, I brew full volume 5-5.5 gallon (~19-21 liter) batches in a smaller 8 gallons (~30 liter) kettle. But use a separate mash tun (converted cooler).

Use a BIAB Calculator such as:
https://simplebiabcalculator.com/
Also:
https://www.brewersfriend.com/mash/Brewer's Friend has many other calculators too, as well as recipe builders

Here's a thread about BIAB calculators:
https://www.homebrewtalk.com/threads/good-biab-calculator.395690/
 
I typically do 3.75G batches in a 5G kettle using a 5G food grade bucket for a dunk sparge. Would a bigger kettle be easier? Would I need to watch it less for boilovers? Sure. If I was buying a kettle I'd probably get a 7.5G. But this kettle was already in my kitchen and it works. An ounce of first wort hops helps keep the risk of boilover down. My most recent batch was 3.95G post-boil at 1.099 original gravity.

Full-heartedly double the recommendation for a wilserbag.
 
If you already have a kettle, I totally understand wanting to make it work...nothing worse than spending money on another kettle if you already have one...there are ways to make it work.

My 15 gal kettle is full to about 1" from the top when I do my RIS. About 25# of grain full volume mash for only 5 gallons of beer.
 
My 15 gal kettle is full to about 1" from the top when I do my RIS. About 25# of grain full volume mash for only 5 gallons of beer.


But that's the thing, you're assuming full-volume mash. Add a simple dunk sparge and you can probably make that a 10g batch. (ETA: With less than 50# grain;))

BIAB does not equal full-volume mash. Do most BIABers do a full-volume? Maybe, probably. But a BIAB with a dunk sparge is as much BIAB as BIAB is all-grain.

ETA: It's also not just a matter of making it work. If I were to get a kettle the size you suggest I need, I'd have to move off my stove and wouldn't be able to do my cleanup in kitchen sink. A just big enough pot allows me to brew where I want to brew.

:mug:
 
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But that's the thing, you're assuming full-volume mash.

Not really assuming full volume mash but that is the worst case scenario IMO.

There are countless ways to BIAB and make beer. I often hold back some water for a sparge myself. Not for lack of kettle size but to improve efficiency. I didn't specifically buy a 3X kettle, I just found a nice large stainless olive oil barrel 25 years ago (Crete) for a great price and it happened to be about 15 gal. So I just lucked out when I recently discovered the BIAB thing.

Full-volume mash is the worst case scenario for kettle size. That's why the "3X rule". It will cover just about any situation or method that you can think of.
 
But that's the thing, you're assuming full-volume mash. Add a simple dunk sparge and you can probably make that a 10g batch. (ETA: With less than 50# grain;))

That is my current thinking as well. I target 5.5 gallons into the fermenter using a 10-gallon kettle. I can get up to about 1.070 with an all-grain batch with a full volume mash. That covers the vast majority of my beers. The big Belgian beers that I brew usually have a good amount of sugar added to the boil, so I could brew a pretty big Quad or Golden/Trippel.

The 4 times in the past 3 years that I brewed beers bigger than 1.070 (3 batches of RIS, 1 batch of a Barleywine) I either added in a dunk sparge, or just reduced my batch size. As a bonus, adding the dunk sparge pushes up my efficiency a good chunk (5 gals of 1.118 wort out of 23.5 lbs of grain). Using some extract is another solid option. I recently tried a stove top batch and was able to get a good 3-gallons out of my 5-gallon kettle by just adding in a easy dunk sparge step (so 1.66x).

If I was buying new I would probably go for a 15 gallon kettle (I actually wish 12 gallons was a common size), but I view "3x" as more of an upper end luxury than a "rule".
 
Thank you all for your input guys.

I'll stick to extract brewing and introduce partial mash for speciality grains for now.

As for the bag i ll go for a big one, i think it is always better to have a bigger size rather than smaller.
 
I'll stick to extract brewing and introduce partial mash for specialty grains for now.

One thing I would note, is that the terms "partial mash" and "steeping grains" are often confused. An article on the topic: Steeping vs mashing - Brew Your Own

But as far as a partial mash...the ease of BIAB can easily turn the concept of "partial mash" (where you using some mashed grains to add character to an extract beer") into more of a "partial extract" (where the vast majority of your flavors and fermentables come from your mashed grains and you use some extract to hit your final gravity"). So instead of getting 80% of your fermentables from the extract, you are only counting on extract for maybe 20% to 40%.
 
Just a note on bags... Wilser's has a sewn-in drawstring to close the bag, but you still need to add a strap to facilitate pulling the bag out of the kettle if you use a pulley system.

BrewBag* already has 4 lifting eyes sewn on, along with reinforcement straps sewn across the bottom in two directions, which appeals to the latent (drunk) engineer in me.

End of the day, they both do what you'd expect from a BIAB bag. BrewBag is more expensive, but has that lifting strap sewn on, which is why I went with it instead of the Wilser product.

*I don't want to insult a forum sponsor by including a link, so I'll let you google it for yourself...
 
No strap needed.

View attachment 734086

Wilser includes a loop for a Prussik hitch (wrap, wrap, pull through).

View attachment 734087

Wilser's Strength Test ...

https://www.homebrewtalk.com/threads/biab-polyester-voile-strength-test.384445/
I'm just going by Wilser's own video and recommendation... that's a pretty hefty orange strap he used to lift his bag.

I find it real convenient to just loop a carabiner thru the BrewBag loops and hook on the pulley system I use.
 
I'm just going by Wilser's own video and recommendation... that's a pretty hefty orange strap he used to lift his bag.

I find it real convenient to just loop a carabiner thru the BrewBag loops and hook on the pulley system I use.

A) He's lifting 120lbs!!!

B) The drawstring has a 200lb breaking strength (likely a single string, making the drawstring or Prussik 400lb, haven't confirmed that).

C) If your problem is with the drawstring, that doesn't require the big step of fully strapping the bag.

D) If your problem is the drawstring's attachment to the top of the bag, use the included Prussik loop.

I'm not knocking the BrewBag, I considered it when putting my kit together. I went with the Wilserbag due to wanting to support a cottage industry, the lower price, and full confidence in the construction of the bag.

I find it convenient to place the Prussik as close to the grain bed as possible.
 
C) If your problem is with the drawstring, that doesn't require the big step of fully strapping the bag.

D) If your problem is the drawstring's attachment to the top of the bag, use the included Prussik loop.
I don't have a problem with the Wilser bag, I just prefer the simplicity and elegance of the sewn-on loops and reinforcing straps. I included the reference so new BIABaggers could see there are multiple options.

Like I said, end of the day, both bags do what we need -- it's personal preference. I paid more than I would have for the Wilser bag, but I think I got more convenience for the extra $$.

My thanks to WilserBrewer for being a supporting forum sponsor. Wish I could say the same for Rex Slagel.
 
I don't have a problem with the Wilser bag, I just prefer the simplicity and elegance of the sewn-on loops and reinforcing straps. I included the reference so new BIABaggers could see there are multiple options.

Like I said, end of the day, both bags do what we need -- it's personal preference. I paid more than I would have for the Wilser bag, but I think I got more convenience for the extra $$.

My thanks to WilserBrewer for being a supporting forum sponsor. Wish I could say the same for Rex Slagel.

:mug: I appreciate that, however I still rankle at...

Wilser's has a sewn-in drawstring to close the bag, but you still need to add a strap to facilitate pulling the bag out of the kettle if you use a pulley system.

It's an incorrect statement.
 
I'm sure they are both good bags. I have never had a problem hoisting a Wilser bag, but I almost always do batches of 5G or less.
As a US based customer I also like the fact that the Wilser bag is made in the US. That may not matter to some - especially Asian brewers.
 
I'm sure they are both good bags. I have never had a problem hoisting a Wilser bag, but I almost always do batches of 5G or less.
As a US based customer I also like the fact that the Wilser bag is made in the US. That may not matter to some - especially Asian brewers.

This.

I've done numerous 10 gal batches with Wilser bags, with 20-25 lb grain bills. Never a problem hoisting 40-some lbs of wet grain out of a kettle.

The difference in ease and security between a bag that has sewn-on loops and one that uses a loop of cord in a Prusik hitch is trivial. Flip a coin.
 
What about sitting the bag inside a deep fryer basket? They are generally made from 304 steel, plenty strong, have handles, and don't displace much volume.
 
The problem I was proposing a solution to was weak bags or poor strapping solutions.

Perhaps an issue with hardware store paint straining bags?

I can't speak out of experience regarding BrewBags, but weak bags are not an issue with Wilserbags and straps are not needed, poor nor strong.
 
The drawstring works great to secure the bag around the top of the kettle during mashing, then you can very simply hook the drawstring to your hoist…
No need for school boy binder clips to fix your bag to the kettle…win

I did a post a while back detailing hoisting options.
Google, “BIAB hoisting w/ ratchet pulley. Rev 1” for details
Thanks
 
No sorry Beermeister I’m out of context here…
I was referring to the fact that w/ pricey brew bag you still need binder clips to hold it to the kettle, and w/ draw string bag you don’t.

I’m actually a fan of multiple bags if that’s what it takes to get the job done!!
 
I have an 8 gallon mega pot and make 5.5 gallon batches. My OG is usually 1.060 or less. With a 10 - 12# grain bill I will use 6.25 gallons for the mash in water and reserve about 1.5 gallons in a 5 gallon bucket that I do a dunk sparge into. Mash efficiency tends to be at least 80% doing it this way. My starting boil is usually around 6.75 gallons and I have to be real attentive when the protein break is at start of boil but works for me.

I use a Wilser bag, went to the local Fleet Farm store and bought a ratchet pully from the hunting dept. for a few bucks. Hook it to the draw string, lift with one arm and pull on rope with other. easy peasy. As he says above, secure the top of the bag over the kettle and no grain spills into the kettle when mashing in.

FYI I let my wife see the bag and she used the second one I had to hold crab apples for when she made jelly, I have to admit it worked really well to let all the juice drip out into a pot :)
 
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