Pre-mash to increase gravity of Grainfather batch

[domdom]

been using the grainfather about a year now. max grain bill i've done is 17lb and i had issues with the water overflowing out the sides of the handle holes on the side. Wanted to do an all grain barley wine and was wondering if i could do a mash in my old cooler as the starting water for the mash in the grainfather. basic idea:
-mash about 6-8lb base grains in my old rubbermaid mash tun with braid.
-recirculate and use this as the initial mash in liquid for the rest of the grain bill in my grainfather.

wondering if anyone knew if this would work to get a higher gravity wort than otherwise possible. only concern off the top of my head would be if it ****s up the mash PH.

 

[pricelessbrewing]

Sure, it's called "reiterative mashing". You'll need to calculate the volumes, and temps by hand though because there's not currently any software available that will do this for you.

Chris Colby has some good information on this method

 

[Jwin]

Blichmann did this on a podcast on the brewing network a while back. At one point he did three mashes. You need to figure out your grain absorption and deadspace/equipment loss for each mash and add that to your target final wort amount. Your first mash will be thinner as a result. Not a bad idea to put a little more grain in the first mash. Conversely, you could take a gallon or two off of your total water needed and use it to sparge the first mash to help efficiency. Cheers

 

[Jwin]

On another note, I would probably use all my water in the mash. Then, still sparge with a gallon. That way, you have extra wort Incase your volume is short. Worst case, extend your boil and add it in after 30 minutes of boiling. Could also just boil it for starter wort for your next batch.
Another idea is to not sparge any of your grain and combine it in your old cooler after the second mash, then gyle a second, lower gravity beer off of it.