I made a very simple "still" once. It worked like this:

In a 25 liter bucket i put a 10 liter bucket filled with mash. I added a aquarium heater in the small bucket and had a constant temperature of 40 degrees celcius.
Then i put the lid on the 25 Liter bucket and waited (and waited and waited). The air inside the 25 L bucket became saturated with alcohol/water and condensed on the 25 L wall.
24 H later about 300-400 mL 40% alcohol was found in the bottom of the 25L bucket.
The quality was very nice! much better than a average fractional still.
To make this work you have to have strong mash, about 20%

This still is for people that wants a simple but effective apparatus. Some parts that is left out in the text and worth mentioning is the different kind of aquarium heater you can use.
1. One of the best one is the Jäger heater SH not adjustable 100W, you can find it in www.aquaristikshop.com (search for jäger on the site) It is cheap and it has a thermostat that is set on 47 degrees C (it thinks it runs dry over that and shuts down). Perfect for our needs, just plug it in and you get the right temperature. Maybe partyman will sell this one as well, we'll see. Unfortunately Jägers green wire can't withstand alcohol. In time it will break down. Thread the wire in a hose and seal with glass silicone and a hose clip.
2. Modification of ordinary aquarium heater: Some have a lock that makes it impossible to get over 32 C. Remove the plastic lock and you can have 50 C if you wish.
3. Those that can't be modified with lock: 99% of all aquarium heaters have a bimetal thermostat, open the heater and force the metal down with a ball of paper so that the thermostat never shut down the heater. Adjust the effect with a dimmer.

  Riku has made a neat modification to the basic model, with a hot air gun he changed the shape of the lid to a dome so all condense was collected. Another way is to tilt the bucket.  This is useful if you want to use it as a prestill your mash before your ordinary still. That way the quality is improved.

After looking over the "double distillation for whiskey" method on your site, I did some playing around with a large (20 litre) version of the ice water "wok for a condensor" design. Because the collected distillate is sitting on a tripod made of copper tubing (nothing special- just three pieces of thin tubing cut to fit into a tripod and support a bowl above the mash) the distillate is collected very hot- making hydrometer readings impossible (yes, you could probably adjust for temperature, but the stuff is still steaming- it would break the proof hydrometer). To get around this problem, I figured out a method of distilling spirit by measuring the amount collected. Here is how it works:

1.start with a mash of a 10%abv, 20 liters total volume, run it through your potstill until you collect the first third. Volume collected= 6,666.6ml (yes, I am this precise in my collection measurements) The temperature you run this first run at is pretty unimportant. On the second run, use the lowest power setting that you have.

2. load the 6,666.6ml of "low wines" into your potstill and run it on it's lowest possible power setting. Collect the first 100ml of spirit as "heads" (don't drink them! use them to start the bar-b-q). Now, collect the next 1,641.6ml of spirit that comes out of the still. With a starting mash of 10%, following these directions, this spirit should come out at 80%abv (at least with my ice-water/wok still it does- suprising since this is the least efficient still design I've ever worked with- make sure to use the LOWEST power setting on your stove). This is your finished whiskey- cut and age it as you wish.

3.Collect the next 580.6ml of spirit that comes out of the potstill as "tails". These are to be added to the mash of your next batch- this separation point ensures no heavy alcohols get into the finished spirit, but no alcohol is wasted.

That's it- out of a 10%abv mash on the first run collect 1/3, on the second, collect the heads, then the next 1/4, then collect the tails (enough to total 1/3 collected out of the second run). This method gives me 4 bottles of great malt whiskey at 40%abv when I'm finished, along with a little more than a half liter of tails for the next batch (you can also save the tails, and when enough has been collected, run out the first 1/4 of the total as a finished whiskey- it should be very good- I haven't collected enough tails to try it yet). This system works just as well for brandy and schnapps. and is usefull when you don't have a nice storebought still- hell, it doesn't even require a thermometer! Using this system, the ice water/wok still can be made with a 20liter aluminum stockpot and a glass bowl to work as the condensor, and it will work just as well as any normal potstill.

The bowl I use for the lid/condensor is glass and it lets me see into the collection bowl to check if it's full- if it is- siphon out the water, remove the bowl, get a face full of steam, then use an oven mitt to grab the lip of the bowl and pour the contents into a pyrex graduated cylinder- make a note of the volume, then pour into an old 5 liter wine jug (1 of 2) that are labeled "low wines". I can only tell when the collecting bowl is full- because of the water I'm looking through (in the bowl) any "full line" marks I put on the collection bowl would not be visible.

I have run across a picture of an old still that had the same tall pot with a tripod supporting a collection bowl (made of copper), but coming out of one side of the collecting bowl (and through the wall of the still "body") is a tube that allows one to collect the distillate without opening up the still. I would like to try this- no time. Making a funnel out of copper sheet, and attaching a length of tubing to the funnel's narrow end, then feeding the tube through a hole in the still body (maybe stopping any leakage with lots of teflon tape) so the tube extends out one or two feet and drops the distillate into a cup would be nice, elegant way of avoiding a constantly steam-burned hand and face.

p.s. when looking for a bowl to work as the condensor, make sure it has a narrow base, or the distillate will fall off of it and miss the collection bowl.
 

These are both based on the solar still, sometimes used in desert regions.  Patrick explains:

When I was a boy growing up in Arizona, USA, I learned how to make a desert survival solar still. I often thought that it might work to distil whiskey. I have never tried it with whiskey but it works to purify water. You dig a hole in the ground as big as your plastic sheet or nylon poncho will cover. You then put chopped cactus plants into the hole. If there is damp earth in the hole then no cactus needed. Put a container like a can or bowl in the bottom of the hole right in the middle. You then place your plastic or nylon poncho over the hole and place rocks around the edge of the covering until it is secure and forms a bond over the hole. You then carefully put a stone in the middle of the plastic sheet, causing the sheet to have a low spot right over the container. This solar still will produce drinking water out of the desert soil. If you were to dump mash into the hole before covering it with the plastic sheet this should produce alcohol. I'm not sure but this may be how they made mescal (tequila) in the old days. I don't know if this would work in cooler climes under 100 deg F.

from http://users.stargate.net/~mshapiro/cfoot.html .. Another method, known as fractional crystalization, is done by inverting the process and freezing the beverage instead of boiling it. This works for very similar reasons to that of normal heat distillation, namely, the differential in freezing points of the two liquids involved. Water freezes at a temperature of 0 C, while ethyl alcohol does not freeze until reaching -114 C.

This allows the water to be frozen out of the liquid, leaving behind the ethyl alcohol, as well as the other alcohols and esters. This produces a drink of a rather different character from heat distillation, as it contains everything except water, while heat distilled beverages leave everything behind except alcohol. Note also that simply lowering the temperature to 0 C will not produce an increase in alcoholic strength. The temperature required for this process is in the range of -15 C and below, but must vary, much as the diurnal cycle naturally does.

This allows crystals of ice to form as the temperature drops. As the temperature rises slightly the alcohol will drain out of the crystals so that when the temperature again goes down and more crystals of ice re-form they are purer crystals of water, containing less alcohol. As this process repeats itself the solution will gradually work its way toward the alcohol concentrations listed in the following table which is adapted from a chart on page 102 of the book, Wines & Beers of Old New England:



Temperature (F/C)	% Alc.
10 / -12.2	8
5 / -15.0	11
0 / -17.8	14
10 / -12.2	8
-5 / -20.6	17
-10 / -23.3	20
-15 / -26.1	24
-20 / -28.9	27
-25 / -31.7	30
-30 / -34.4	33

The trick with freezing is to partially thaw and refreeze a few times to promote larger pieces of ice--the frozen cylinder with a heart of alcohol is the consequence of diurnal cycling in a barrel over weeks.

Don't bother trying to get a frozen heart of alcohol- it's not really needed. Just fill a gallon (4liter) milk jug half full of your beer/wine, let it freeze solid in the freezer, then get a one quart (1liter) wide mouth jar, and stand the milk jug upside down in it. It will take about four hours or so, but eventually as the ice slowly melts (don't apply any heat), the jar will fill up, and you will have just about doubled the alcohol (by cutting the volume in half). using a 10% wine this method will turn a half gallon into a 17% quarter gallon. I have not tried sticking this 17% wine back in the freezer to see if I can get any more ice out of it, but it's worth a try. It also seems to be the easy way to get "distiller's yeast" performance without fooling about with yeast starters and the like.

More correctly known as "fractional crystillization", the practice of freezing an alcoholic mash then removing the (concentrated)alcohol was used in ancient times before distilling was known. The problems with trying to purify alcohol this way was that not only did the ethanol come out of the block of ice, but so did all the nasty higher and lower alcohols that cause painfull hangovers, and there is no way to separate them from the ethanol by freezing.

The other reason you may have already seen: if you have ever put a bottle of vodka in the freezer (a traditional method of serving), you will notice that no matter how long it is in there, it never does anything but turn slightly thick, like syrup- no water freezes out once the alcohol gets up to 40%. Unless you have easy access to a source of liquid nitrogen, etc. so you can "super cool" the mash, then bring it's temp back up in a controlled enviroment so as to melt off various alcohols at various times, it's not worth bothering. Even then, it ain't worth it-the energy needed to keep the mash that cold would exceed the energy requirements needed to distill it.

Home winemakers use this technique to make fortified wines without using distilled spirits- Put the mash in a plastic jug, leaving enough room for expansion, then put this in the freezer until it's a solid block of ice, then invert the container over a collection jar and gather everything that melts out until you have collected half of what is in the jug. With a 10% mash, this will come out to about 17% ABV.

• Apple-jack.
  Make a good strong cider, as described in the recipe given, then put it in a sealed cask. Place the cask in some place where it can freeze through very slowly. In Canada this is doen by digging a large hole in the ground and covering the cask about three inches deep. When the thaw comes, the cask is at once dug up, and the contents will be found to have separated into apple water and to pure spirit. The spirit will be in the centre of the cask. The ice must be broken with great care, and the liquid spirit in the centre carefully run off. This is the apple-jack. It should nver be drunk undiluted.
• Cider.
  Any apples will make good cider, but cider apples are best. If sweet apples are used a mixture of bitter apples or crabs is to be advised. Put the apples into a wooden tub, and smash them roughly with a wooden balk until they are a crude pulp. Cover the tub and leave for twenty four hours. Then put the pulp through a press or crush it in a strong hessian bag. As the juice runs, put it in a cask, and see that it is quite full. Keep the cask in a warm place and allow it to ferment spontaneously which as a rule it does very quickly. At a normal autumn temperature, the apples will ferment within 48 hours. Top up the cask with apple juice until the first violence of the ferment has subsided, then put the cask in a cool place to finish. Do not bung down hard until all sounds of fermenta tion has ceased. It will be ready to drink in three months, but will be better if left for six. It will improve if well racked. For sweet cider add sugar at the rate of a pound to a gallon, or more to taste. (Through the book, Mary is a firm believer in natural fermentation. I'd play on the side of caution, and direct the fermentation by adding a suitable yeast.)