Originally By Tony Ackland
The First RunBefore you use a still for the first time, be it made or bought, make sure you have cleaned it well - get all the grease, solvents, polish residue etc off it.
To clean a new still, Ted advises :
The first run should be a water-only occasion. Put enough water in it to prevent it boiling dry, and let it rip. The steam will :
Water only is good for checking if it leaks, seeing how long it takes to get up to temperature, and cleaning out any dirt or oils etc left over from construction. It also lets you check that your final condenser is efficient enough to fully condense all the energy that you're putting its way.
But it can't be used for "practicing" distilling. With water only, reflux is meaningless, as there is no second component there to enrich or strip. It will only put out a vapour in the high 90's (depending on altitude, thermometers etc) and nothing will change the way it runs.
As a practice run, add some cheap alcohol - eg old beer or wine etc to the water and see what happens. The more alcohol present the more marked the change will be. You should notice that the head temperature is quite a bit cooler initially, slowly increasing as you run out of alcohol. You may even have enough there to try seeing what different reflux ratio's do. You'll notice too that the flow rate of distillate will be greater than that during the water only run, as it is easier to vaporise alcohol than water.
Then its time to do the real thing. Make up just a cheap sugar-water wash, ferment it out fully, let it settle, then decant into the still. Make sure that you leave about 1/4 of the still empty as headspace at the top for foam, bubbles, splashing etc. Bring the still up to boiling temp, and try it with as much reflux occurring as possible. You may want to change the plumbing on your cooling, so that you can alter the flowrate in the "through tubes" independently of the main condenser.
Ideally you'd want to start your column off under total reflux. That lets you concentrate up any impurities (foreshots) and remove them first. With your design, total reflux may not be possible, and you may just need to settle for as much as you can. Find out how much that is. You'll notice that the temperature should stabilise around 78-low 80's. As you decrease the reflux this will rise. Take this first run as an experiment - don't worry too much about the quality that you collect at. Instead, use it to see the relationship between the cooling water flowrate, the amount of reflux it causes (how much does the output slow by?), and the resulting purity. Try it with no reflux, and compare the difference. Listen to the sounds its makes - often you'll pick up changes by ear - gurgling , hissing, thumping etc . Try a whole range of different conditions and learn what your stills response is. Measure the distillate flowrate under these different conditions. What's the corresponding change in head temperature (and purity) Remove the column insulation and note any changes that occur to quality. Learn how long it takes the head of the column to re-equilibriate after you make a change to the reflux - some take quite a while and shouldn't be fiddled with in the meantime. How touchy are the control valves ? As the boiler starts running out of alcohol, see how much more reflux you now require to get that same purity that was so much easier at the start of the run.
On those first runs, really play around and learn your still. Keep all the distillate you collect. Even if its got some nasty heads or tails in there, its simply a matter of redistilling it at a later date, and it will clean up nicely. No point ever throwing good alcohol away.
John advises ...
I suggest that when you are ready to roll, begin with a couple liters of water - that will show you how long you need to heat up to around 79oC, which will become your distilling temp. But with the water in your kettle, just let it go on its own - fiddle with the cooling rates, etc.
The second run - I repeated the couple quarts of water but added a bottle of the cheapest wine I could buy at the store, and ran that. Now you will be in alcohol distilling territory, and you can observe the way the boiling rate really runs on its own, and what it does at around 78 or 79oC.
Third run - run 4 quarts, and this time as much old or whatever wine of any kind. I had some fermented apple juice so I added that in. This is just to get more experience.
Fourth run - a sugar wash.