Kettles, Kleaners, Konductivity.

Greetings, I started out w/ Keg-kettles w/ heating elements and spigots. I direct fired the kegtle, in addition to the electircal heat. Never did a decoction in these elemented kettles, can't really stir w/ the element in place. The Polarware SS Kettles are much better than converted kegs. For a direct fired brew kettle, I find aluminum to be superior to stainless. Isssues as I see 'em. 1. Conductivity, hot spots, scorching: Materail Conductivity Cost (W/m-^C) (From Matweb) Copper 360 $1kb? Aluminum 180 $100 400 SS 27 $100 300/18-8 SS 16 $200 I've never used copper, but in my experience, aluminum is a superior conductor compared to SS. Granted the Al needs to be a bit thicker, so the actual conductivity may be only 5 times the values for the Polarware pot. The chances of scorching are much lower w/ aluminum. Aluminum works much better for decoction mashing. A thicker, better conductor means fewer/no hot spots. 2. Cleaning. Commercially, aluminum is not a good option since the commercial cleaners (strong caustics) dissolve aluminum, but few compmercial operations are direct fired. Also, commercial brewing is a high risk occupation. (get the numbers from OSHA if you don't believe it.) Number one hazard is burns, from the strong caustics used in cleaning. My question is this. What sort of chemicals are you using on your home brew kettle? Why? My aluminum kettles take a bit of beer stone, and keep it until I over-do the acid/pH adjustment. 3. I'm not a fan of spigots in the brewkettle. Impossible to clean, and easily plugged. I like the siphon/duck/whatever. 4. I'm not a fan of false bottoms. Never worked that well in the mash tunn (Sabco), so I'm back to slotted pipes in a cooler. In the kettle, I've had trouble w/ scorcing under the false bottom (Sabco). Quite possibly, that issue is reduced or eliminated w/ a "real" kettle. (e.g. Polarware). 5. Flavor: Not an issue. See Jeff Donahue's article on same. My keg kettls are wired for heat (1100 watts at 110v) and have spigots. I've retired them "upstairs) to HLT use, and they work fine for that. A spigot on the HLT is very convenient. I'm as big a fan of stainless as the next guy, but it's not a very good conductor. Cheers, Jim -- ------------------------------ * * Dr. James Lee Ellingson, Adjunct Professor jellings(a)me.umn.edu * * University of Minnesota, tel: 651/645-0753 fax 651 XXX XXXX * * Great Lakes Brewing News, 1569 Laurel Ave., St. Paul, MN 55104 *