The Vorlauf and Lauter
By now your grain bed should be well-set, and the conversion complete, and the wort is ready to be run into the kettle. The ensuing step is crucial, and one that will, yet again, avoid the horrors of a stuck mash. When you are ready to run off the wort for recirculation, open the valve a little at a time and observe the flow. Work patiently over the next few minutes until you have an even, easy flow. Opening the valve all the way, right away, could send the finer portion of the mash surging into the manifold and clogging it…very bad news.
Once established, keep the flow steady and slow, both during recirculation and during your kettle fill. Take up to an hour or more to fill the kettle: it will pay off with good extraction and no flowage issues. Keep an inch or more of sparge water above the mash during the lauter and don’t be afraid to lightly rake to top of the bed if there is obvious channeling. Devise a sparge water diffuser with foil to keep the bed intact.
As you will be doing a full-wort boil in a full kettle, some precautions are necessary. It is wise to let the wort boil for about 10 or 15 minutes―it will become obviously more sedate at this point―before adding any hops. Boil over will drastically throw off your bittering rates and overall balance, especially with hop pellets. Target gravity isn’t something that should be stressed over at first: ballpark it. Monitor it nonetheless throughout the boil as a way to gauge your proficiency, something that can improve in the future.
Now that you have contemplated the plunge, go ahead and take it. Unfortunately, many homebrewers―this one included―learn some of these more obscure tricks the hard way. A day that you excitedly look forward to and meticulously plan for can turn into a nightmare in a hurry with just one boneheaded oversight. Pitfalls are certainly an effective way to learn, but brewing holds enough surprises and chances to worry and fail as it is. Chill out, fret not, and brew an all-grain beer.