My mash tun cooler drain is a little bit off the bottom , do I need to allow for this or just tip up the cooler when draining ?
Tip it up a little. I prop the far end of mine up while I’m running off. There will still be some deadspace but with a little trial and error you’ll figure out what that volume is that’s left behind and can account for it in your volume calculations.
+1
I use a phone book, or other similar sized object, when doing my second runnings.
I wait until the runoff stops, then tilt mine.
Batch sparge with a rectangular cooler? Tilt away.
Fly sparge? Just add some more sparge water.
Batch sparge in a round cooler/false bottom that pulls wort from the center? Tilting won’t make a difference.
I have a dip tube attached to my braid so that I don’t need to tip the tun. Before I added that, I just tipped the tun at the end of each running.