I was just answering FOC post, I sparge, I sparge slow, its not just only about efficiency it is about tannins as well. As I said I will be trying a "no sparge" WEAL has tweaked my interest, there is no modifications needed, today I bought some threaded bar and 2 nuts from Bunnings, this will go the full width of the malt pipe and sit on the retaining lip, while also being my lifting handle. When I try the "no sparge" on the Guten I will be adding about $4.00 more worth of base malt to the grain bill, this will make up the loss in efficiency, I don't have to think about heating up sparge water and I know I will have less tannins than if I had sparged, that's what I call stupidly simple. If anyone asks for advice I will give it, if they don't want to follow it that's fine by me.That sparge time may be relevant on a 3V system, but a sparge on this system can take a mere 10-15 mins and still give fantastic efficiency.
Regarding pulling tannins from the grain bed during your sparge - if you're doing that in any appreciable amount, then you're either sparging way too hot, have stuffed up your pH, or must have pretty much ground your malt in to almost complete flour (in which case you won'be be sparging, because it will certainly be a stuck/fully compacted bed).
As @FarsideOfCrazy pointed out, there really isn't any appeal to no-sparging here - you get lower overall efficiency and you have to modify the equipment to be able to fit a full batch. Sparging is stupidly easy on this - just heat the whole volume of water, then drain off the sparge water in to a bucket and let it sit until you need it. You don't even need to try to keep it warm or anything because it doesn't matter. Hell, you could probably just pour the entire bucket over the grain bed at once and still get better efficiency than no-sparging.
(For the record, I'm a former no-sparger from my previous BIAB setup and I loved it then. I am just completely convinced that it is worthwhile sparging with these systems)
If you want to just pour the full bucket of sparge water over the grain bed that's fine by me too, but that is something I will not be trying.
That is just the starting point, the efficiency I got on the first batch was 86% so 15% extra base malt should be about right.How did you arrive at 15% Reg?