Computer controlled mini LM reflux still

[wysiwyp]

The thing I like most about this hobby is the sheer number of different fields of knowledge and skills that are useful. My current project involves all of the following:

metalwork
welding
plumbing
soldering
electronics
computer hardware
computer software
physics
chemistry
cooking
drinking (that's the whole point, isn't it?)

I wanted to build a still that I could use to make small batches of gin or vodka. I use a 7.5 gallon pot still made from a beer keg with an internal electric heating element that works great for stripping runs, but it needs a minimum of 2 gallons of liquid to keep the element covered and I didn't want to have to run that much every time. I decided to build a small 1 gallon still.

The boiler is made from a stainless steel tank that I got at the local surplus store. It is about 5-1/2 inches in diameter and was about 18 inches long when I bought it. It seemed to be a manifold of some sort, with threaded nipples attached at either end and several down the side. I have no idea what it was used for, but it had traces of some sort of sediment inside. I cut it down to a length that I had computed to result in a volume of one gallon, but because the ends and walls were a lot thicker that I had assumed, the final volume turned out to be about 80% of what I had planned. After cleaning the inside thoroughly with a wire brush, I welded on ends made of 1/8 inch thick SS, and attached 1 inch threaded SS fittings for the heating element and vapor outlet, and a 1/2 inch fitting to the bottom for a drain. I say "I" welded it, but in reality I needed quite a bit of help because this was my first welding project and I haven't quite got the hang of it.

boiler.jpg

The heater is a 1500W 120V electric water heater element screwed into the fitting on the side near the bottom. It is short enough to fit sideways into the boiler. The electrical connection is made from a replacement plug that is connected to the element with copper strips cut from a piece of sheeting. It is enclosed in a plastic cylinder made from the neck cut from a large bottle of Listerine mouthwash which coincidentally fits perfectly and is made from PETE plastic which has has a high enough melting point to not be a concern.

heating element.jpg

The column is a 44 inch length of 1 inch copper with SS packing. I am using the condenser described in this post http://homedistiller.org/forum/viewtopi ... 17&t=11669, however I modified it to run the outlet tubing through a section of 1/2 inch copper that the coolant runs through. This was done because the alcohol coming out was sometimes warm.

outlet.jpg