I put everything together and siphoned the wash into the boiler, avoiding the sludge at the bottom - it was pretty hard getting the hose to play nice and aim it at a particular point. I may need to wrap the siphon hose in wire or something to be able to control it better. The other thing I did was to place a short bit of stainless tube into the end of the siphon hose so I could easily see the end moving around through my hazy wash (using a clear hose). The other thing I might need is a checklist, like a pre-flight checklist. My still has a number of connections that need to be tightened up before the run, and leaving one loose could end up in a leak.
I cranked it up, and it came to boil very quickly - I didn't time it, but I'm happy with the timing on that side of things. There was enough time to begin sanitising bottles etc. and setting up a little table for organising things. Once the column came up to temperature (it went up to 88-90 celcius and within seconds dropped back down and sat on 77) I left it for 2 hours to equilibrate. I think this is too long for the big column I have - there's a lot of heat and a heck of a lot of packing, so I think equilibrium occurs sooner - but how could you tell? I kept an eye on the water, and whenever it felt 'too warm' I turned on the hose that was sitting off in the tub with the pump.
At this point I made my first major mistake. I let the water really get too warm, and even though I had some copper wire wrapped around the water hose coming out of the condenser, the hose just flattened itself out and all flow ceased. The column immediately went into overdrive with vapour blasting out the hole in the top, and ethanol instantly bleeding out around the condenser press fit at the top. I tried massaging the hose and repositioning, but the hose remained stubbornly flat and couldn't be opened up. This was only for about a minute, and at that point I shut the gas off. All the while that ethanol was bleeding out the top, it was only making it a few inches down before vaporising so I could be sure it wasn't making it down to the burner. As soon as I shut the gas off, the bleed stopped and vapour stopped rushing out the top - this gave me a few minutes to work on saving the situation. When they say "never leave your still unattended", treat it like a two year old who has a box of matches. It is a very dangerous thing to turn your back on for really any amount of time.
I cooled the water in the tub down and re-established the flow back through the condenser. The hose was still flattish, but flow was still good. I fired up the gas again, and this time kept the hose into the tub just on a trickle - it was surprising how little flow is required to keep the water cool, so I'm not too worried about wasting a lot of water. The condenser was back to working nicely again and I left it equilibrate for another 20 minutes - I must say that whatever equilibrium was there may have been messed up, but I was banking on the fact that everything was still hot to accelerate this process a second time.
The next thing to go wrong was my flour seal in the main two-piece column join began failing at an increasing rate - ethanol was busting out and leaking down the column. Once again, it was vaporising before it could get anywhere near the flame, but the leak was expanding and escalating at an alarming rate. For this particular problem I grabbed some electrical tape and started off with a loose wrap over the join/flour, doubling back a couple of times with a tight wrap. The leaking stopped, there wasn't a single drop coming out. In future I'll do the tape in advance; in the end it pealed straight off very easily, and if done at the start I don't think the product will make contact with the tape, then end up back in the still. I don't think that was the case on this run either, even though parts of the flour were initially breached.
I was determined to make the run work. There was now no leaking whatsoever and temperatures were under control all round. I took foreshots, maybe between 50-100ml, basically guessing the smells because I don't know what to expect. Then I went for the heads. I separated ethanol out in smaller vessels during the heads, but couldn't really differentiate right up to 1 cup measurement, so I kept that aside as heads as per The Compleat Distiller. I started on the hearts, keeping an eye on the smell and the taste, as well as the column temperature. I knew from the test run that once you run into tails the temp starts rising rapidly, but I was still keen on using smell & taste to watch out for the tails.
Along came a mistake in judgement. I knew that after 6 days at ideal temperatures, this particular wash *should* achieve 20%. So in that respect I was banking on 5L give or take some heads & tails. I did check the wash at 6 days and the hydrometer had a reading of .85, so that suggested to me that there was a high alcohol content. All these assumptions led to some complacency on my part, and the tails came in way before I expected them to. Because I figured I was dead in the middle of the run, I wasn't so cautious about separating the mix and smelling/tasting - it was all supposed to be the good stuff. So, I *think* I ended up with a bit of tails in the output. The start of the hearts run had no malty odour at all, in fact it smelled very clean. As soon as I could smell something was up (a funny malty sort of smell), I kept that lot separate until I could work out just how different it was to product already taken. It was obviously getting stronger in smell, so I shut the bokabob down - I didn't want to take the tails, but in hindsight if there was another couple of litres of tails in there, I probably should have grabbed it for the next run.
My other indicator - the temperature gauge - also failed me once I got towards the tails. It sat rock solid at 77 degrees c and I had been checking that I had a constant signal (remote thermometer). But I got complacent and started checking the temp and not the signal. The signal had dropped and the temp stayed on the last known reading. These are brand new batteries - the thing had done that during testing, but hadn't done it since I put new batteries in, so I figured that's all that was wrong. It's obvious that the unit is faulty. In reality I think it is something that would become less important as time goes on for this particular build. Once my column is fairly warm to touch halfway up the condenser, then I know vapour has reached the top, so equilibrium can start. From that point it's all smells and taste & spit. The bokabob slant plate design I think allows for outstanding consistency of results and my column appears to be able to maintain temperature and reflects all documented attributes of operation - I'm very ecstatic about that.
There is a *slight* malty smell about the end product, I've yet to taste it properly. A taste & spit test didn't seem too bad, I'll be able to make a better judgement when I make a rum mix drink that I normally have to see how much it varies in taste and whether it gets on the nose. Total output was 2.8L at 90%. Mid run it was reading 95% so I suspect there are a bit of tails in there - if the drop is correctly indicative, then perhaps 5.27% tails were introduced at the end. It's probably still better quality than what a crappy quality still could produce easily, but nowhere near at the level you'd expect from this rig - all due to my stuffup. Nevertheless, I brought the mix down to 40% which I verified with another alcohol meter test. This online calculator is very handy for getting your dilution right:
http://homedistiller.org/distill/dilute/calc" onclick="window.open(this.href);return false;" rel="nofollow
Here's the setup just as I was about to crank it up:
Anyway, I hope that's food for thought for other newbies and gives some hope for those who are about to take the leap and fire up their still for real for the first time.
