BIAB Crush

I am all set to brew my NB Bavarian Helles using the BIAB method. I Do not yet own a mill so I ordered the grain crushed. I have an attachment on my Kitchen Aid mixer that I use to grind wheat for bread. It is a lot like the old Corona mills that we used before the hobby made roller type mills available. (I have a Corona too). Anyways, I have read that with BIAB a finer crush is good to improve efficiency. So my question is this: Should I crush it again? I know this is hard but if so, how fine should it be? About twice as fine maybe?
Thanks

If it’s your first try at this method, I wouldn’t crush again: just brew it and see what kind of efficiency you get so you can set a baseline. But if you decide to crush, you can take the grain all the way to flour if you like because you don’t need intact husks for lautering.

I’d be tempted to re-crush if you don’t see a good amount of flour in your current crush. I’d want the husks intact since this still has to drain out of the bag. A giant sack of wet flour is not what you’re after.

BIAB doesn’t have to result in lower efficiency. Its really no different than using an MLT. If anything it might be better wince you really have no dead space when you pull the bag out of the kettle for it to drain.

FWIW I’ve gotten 91% efficiency with BIAB (though I do a 10 minute ‘sparge’ where I immerse the bag in 2G of 168* water). No sparge you can still get great efficiency, especially if you squeeze the bag.

[quote=“tom sawyer”]I’d want the husks intact since this still has to drain out of the bag. A giant sack of wet flour is not what you’re after.[/quote]I basically powder the grain and shred the hulks entirely and it doesn’t impact draining at all. Then again, I’m using nylon paint-strainer bags, which hve a tight but not super-tight weave, so it might be a problem if the OP is using something with a fine weave.

I use this guys bag (polyester), and have had issues draining with no husk material (rye/wheat beers) to break up the mash.

I vote to not crush further.