Hello. This is my second post, so please bear with me. I've done 5 BIAB batches, but not for a couple of years so I'm relearning. Plus I am trying to delve into everything more deeply to get a fuller understanding rather than just following steps.

I have a formula from Brewing Classic Styles that I made a couple of years ago and want to repeat. My notes from that batch are not good... My main questions are:

1) Is there an increase in grain bill when moving from sparge formulas to BIAB formulas? I see differing opinions on this. In Palmer's main book he has different amounts for 2 sparge methods and for no sparge (BIAB), but in BCS which he co wrote there isn't a clear mention of this. Also, a different calculator that I tried out (nbsparge) factored in a 1.27% increase in the grain bill when I entered the original formula from the BCS book. Yet I see other people not recommend an increase when going from a sparge intended formula to BIAB. The Biababacus seemed to actually DECREASE the size of the grain bill a bit, and the hops addition as well, once I entered everything including kettle dimensions and boil time...

The calculator that I looked at seems to be based on equations by a Ken Schwartz, but I can't find a way to copy it to this post, and any attempt to find it again on the internets does not work. I have it as an Excel file but I can't find a web address to copy here. Here's a screen shot of the excel work up:
(I don't know if any of the attached files will translate...)



I have to tell you that when I last brewed this beer I squeezed the heck out of the bag after mashing. It was pretty hot and heavy, and I had done a mash out. My values were all pretty good , but I had not increased the grain bill from the original formula, so, in the interest of doing things right and being able to repeat or, dare I say it, SHARE formulas and procedures I would like to get this nailed down.

2)I have thought of doing a partial mash, reserving a gallon or two of water in another container and dunking the bag into that container for a couple of minutes to rinse the grain after mashing. I though of doing this because my neighbor does slow sparging and produces excellent beer, and I want to be able to move in the local homebrew circles with pride. ACTUALLY I just thought I might gain a couple of gravity points by doing this instead of squeezing the bag. Any thoughts on this?

I use pellet hops and liquid yeast packs, so I tend to have a lot of break and trub. I use a racking cane with a little hole about an inch up and rack before fermenting. Everything is sanitized well.

Thanks for any help. OH. Do I get an email on my home email from BIABrewer or just check back here directly for replies? Thanks again.

Thank you for replying. I did run this through the Biababacus, and was surprised that it suggested reducing the size of the grain bill, and increasing the hops addition (when I entered desired IBU as 40), but admittedly it was my first use of the Biababacus. I'll go over it again and post the results. There is an excellent chance that I missed something, or things, in my data entry. Or maybe it's all good and the batch will work out just fine!

I don't know if my shop has a hop sock, but I will enter Yes into the cell and try to get one. I'd assumed that the pellets were too fine to be filtered out by the sock but it is worth trying out.
OK. That reduced the grain bill even more!

I think I will copy the BIABacus (I corrected my spelling!) worksheet now and send it on, and see what people can tell me. Thank you in advance.

Well this has certainly taken me a long time to reply! I have attached final BIABacus report of the beer that I made in July. Overall more chaotic than I had planned on due to the paper bag of malt ripping and the very hot day, but we got a decent beer out of it. Following the BIABacus recommendations mostly, yielded an ESB that seems close to the model. Perhaps a little more bitter/dry but very clean tasting. No esters noticed.

I don't know if file is attaching. Please let me know. Thank you.