I've run 3 5 gallon batches of gerber wash. Just checking in with my results so folks can tell me what to do to improve and catch any obvious mistakes I'm making.
Using the 'standard' gerber wash recipe for the most part, adding a little ascorbic acid to drop PH. Starting gravity is about 1.87, final gravity was about 1.01 so about 11.5% ABV. My boiler pot is only 16 liters, and the handle rivets leak if I fill it more than about 13 liters, so that's the size of my runs.
I load the pot and bring it up over high heat on a large electric burner. It takes about 35 minutes to get it up to about boiling, which is plenty of time to assemble the still, apply the biscuit and make sure everything is looking good. I'm using a 2" bokakob LM still with about 1 foot of 2" reflux column under it with a couple copper pot scrubbers tossed in. Fire up the condenser as the steam comes up the column, let it full reflux for about 25 minutes.
Draw off the foreshots at 1 drop/second. I've been pulling between 40 and 60 ml. I take off a little extra, as there's probably 10 ml of liquid in my still's takeoff valve when I first open it up. I take the heads next at 2-3 drops/second, and this takes maybe 2 hours and 15 minutes to take off around 600ml of heads. I open up my takeoff valve a little wider for 3 drops/second for the hearts, taking off about 520ml, which takes about an hour and half. I close down the valve back to 2 drops/second to take the tails, and pull this off until it don't burn no more, last run it was about 265ml.
I'm doing my cuts by measurement rather than taste at this point. I don't feel ready to make those calls yet as a newbie at this, but am starting to taste things a drop at a time and try to get a feel for it. My taste and smell are decent for culinary purposes, just need to get used to sniffing and tasting booze instead of food.
So do these numbers and and process sound about right? I can't say I've made anything that I think tastes all that great yet, but I'm being patient and know I won't be making any Woodford Reserve right away (I wish!). Nothing's been aired out, as I've been dumping heads, hearts, and tails into a dit da jow recipe, which is chinese medicine for buises (and is applied externally, not drunk). That project is about done (1 gallon jug filled with the results of these 3 distilling sessions), and I'm now thinking about saving some to drink.
I'm on an electric burner, and am working on finding a big cast iron skillet to put between the burner and the pot to regulate the temp. Most runs I run the burner at Medium, but last one I tried it on Low to try it out and it still appeared to work fine. Less cooling water and less electricity used, so that's good, but does that mean that there was less reflux going on? I measured the spirit around the end of the heads and it was 87% ABV, which I'm guessing is pretty good for a 1 foot reflux column.
Temps always seem a little high, not sure if it's my thermometer, it's placement, or if I'm running the still too hot. At the end of my 100% reflux phase before I take off the foreshots the column temp is around 172F / 78C. By the time I'm taking the hearts temp is up to 176F / 80C. From what I read in this forum people seem to be pulling foreshots at 160F / 71C and hearts at 172. Anything wrong with my temps? I know things go up and down a bit due to being on an electric burner . . . I'm also going to check my thermometer today in some boiling water to make sure it's not reading 5 degrees F high or something.
Any and all feedback is welcome, I just want to check in and make sure I'm royally screwing something else. Thanks to everyone for the help and for sharing your experience with us new-timers.