BIAB advice re. milling and bag

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I understand that BIAB mash efficiency can be improved with small mill spacing. I'd like suggestions for best mill spacing and bag microns. Thanks.
 
I think the objective for the bag is basically to keep the debris out of the wort, so fine enough for that, after you crush the grains.

On the crush, I got this straight from Anvil: “the depth of a credit card”
Some grains are bigger than others, some are husk-less. you may need to separate some of the grains; rye is like 2/3 the size of 2 row for example.
If your mill won’t easily crush to ‘credit card’ depth on a single pass, you may need to double crush to ensure you have a consistent crush of the grains. You may also need to separate them ; I crush rye a bit smaller because if I run it through the mill at the same setting I use for 2 row it barely gets scuffed.

And yes, a more fine and consistent grain crush will get you better efficiency doing BIAB brewing. Rice hulls will help as well. They are inexpensive, don’t need to be crushed, impart zero taste to the beer and improve the flow of wort over the grains.
 
I have had my mill down to 0.022" spacing. It works, but if you recirc through a herms it gets stuck alot. i settled on 0.028, gives better flow and still retains decent efficiency.

2nd on the rice hulls, they work wonders
 
The brew store does mine, but I tell them I'm BIAB when I make the order, and I normally get a note back on my receipt that says they double crushed it. They are good guys.
 
I use a false bottom an full recirculating Mash setup but I also line the kettle with a bag. It helps with stuck sparges and allows for a finer crush.
I had been setting my rollers to .35 (feeler guage) but I had a hell of a time once the rollers got a little worn. I mill directly into the mash liquor for dough in and it was really a mess trying to keep the grain moving. I've always gotten good efficiency with that crush and not had too much trouble with stuck sparges.
I found some advice about double-milling and tried that today. A little more time and grain-handling but worth it for the smooth operation. I milled into a couple of containers with the rollers set at about .060 and it ran through beautifully. Then I set up my mill over the mash tun as usual and set the rollers to .035 as usual. Again, it blew right through the grain without jamming once.
Bottom line, as noted
 
... I milled into a couple of containers with the rollers set at about .060 and it ran through beautifully. Then I set up my mill over the mash tun as usual and set the rollers to .035 as usual. Again, it blew right through the grain without jamming once.
Bottom line, as noted
I was getting kind of frustrated with my old 2 roller mill, like yours, the wheels were worn, getting stuck frequently and often I had to double crush. it was only a few bucks - I used gift cards to buy it, but it was taking me longer and longer to get it and when I checked online I got mixed reviews on 2 roller, 3 roller, big rollers... I treated myself for Christmas and bought a Spike mill.

FFS that thing is fast. Literally I can crush 12 pounds of malt in less than 2 minutes. Ok 5 minutes if you count finding the bucket, plastic bag liner, mounting the mill, plugging it in, turning it on and milling the grains. It was NOT cheap by any stretch of the imagination. But it is easily 3 times faster than my Amazon sourced 2 roller mill when it was brand new.

The only time I have to mess with it is for different sized grains. I’m sure there are lesser priced options that will work, but I figured in for a penny, in for a pound.
 
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I was getting kind of frustrated with my old 2 roller mill, like yours, the wheels were worn, getting stuck frequently and often I had to double crush. it was only a few bucks - I used gift cards to buy it, but it was taking me longer and longer to get it and when I checked online I got mixed reviews on 2 roller, 3 roller, big rollers... I treated myself for Christmas and bought a Spike mill.

FFS that thing is fast. Literally I can crush 12 pounds of malt in less than 2 minutes. Ok 5 minutes if you count finding the bucket, plastic bag liner, mounting the mill, plugging it in, turning it on and milling the grains. It was NOT cheap by any stretch of the imagination. But it is easily 3 times faster than my Amazon sourced 2 roller mill when it was brand new.

The only time I have to mess with it is for different sized grains. I’m sure there are lesser priced options that will work, but I figured in for a penny, in for a pound.
Nice!
The guy who I just bought my unitanks and chiller from is selling a Malt Muncher 3 roller for a reasonable price. I'll snag that thing as soon as I can. My mill gave it up completely the last time I brewed (sheared a pin on the roller shaft) and I had to make a run to the LHBS to mill before I could proceed. I ended up rebuilding it so I wouldn't have to pop for a new (used) one immediately. The double-crush that I did today really worked well but it was slow. The second mill actually went pretty quickly but it always seems to take a long time to get through 25 or 30 lbs for a big batch. I'm hoping that the 3 roller will be a little faster. If I was brewing a lot more, I'd be tempted to spend a few hundred for something really solid but I'll get by pretty well with the Malt Muncher, I think. :)
 

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