Ermm, i think i'll try to answer everything you ask
It's not instantly failsafe - you need to set it up so the flow of wort is not too strong in a particular direction. If the wort is swirling in a circle around the pot, it'll be digging out the bed and channeling. So you need to jiggle the "bowl" around a little to get the flow out of the 2 sides nearest the edge of the urn/pot to be roughly even and not too strong, and then allow some flow to escape in other sections (you may need to tap some divots into the edge to do this) to help negate a circular flow around the pot. Dunno if that makes sense or sounds complicated? It's not - takes ~1min to arrange it &/or correct it to ensure fairly even flow.
TBH, i'm curious as to whether the soup ladle would be as easy to use to achieve this. It may be, but i've found the ability to easily manipulate the pliable foil very convenient. Maybe the rigid but uniform edge of the ladle would make it just as easy.
When i stir the mash, i stir the whole lot. It's to allow rapid dispersion of the ramping heat, as i use an urn and i've had issues with using solely recirculation to achieve this - i know that should work fine. It doesn't. And my current method works nicely. Plus i believe stirring the crap out of the grain on the few ramping steps i do helps free up more starch for greater efficiency. FWIW, i think i've nailed a few minor issues with my processes so it's probably about time to have another go at the 100% recirc gig.
Anyway, those shenanigans aside, the basic concept should still be solid - when you're ready to recirculate, set up your little foil bowl, make your adjustments, and let it work its magic!
Yeah, you need a decent amount of time to recirculate to get the clear wort. I've found 20mins is minimum, 30 mins is best. Obviously if you're recirc'ing throughout the mash schedule, it'll be plenty of time.
These days, i normally set up my recirc in the 72°C-to-78°C ramp. That makes for ~10-15mins of time, plus another 5-10mins of recirc'ing to clear it, plus ensure most/all of the mash bed is getting to 78°C by the time i start draining and sparging.
As always, there's a bit of a trick to getting the flow rate right - a balance between getting a fast flow to stop the element overheating the wort & to distribute the heat steadily through the mash bed, but not too fast that it sucks down the mash bed and compacts it (Rice Hulls FTW!).
The wort in that pic would've been as above, stirred regularly throughout the mash schedule until the 72->78°C ramp. Then recirc'ed (break/cut up the protein sediment slightly across the top ~1cm of the bed) during the ramp and for another 10mins or so.
I hope that explains it (& you haven't fallen asleep!) :unsure: :lol:
