The following video is a video of me building a concentric distiller. There have been several of us working on this concept, design and construction. This is a good version of some of the ideas we have gathered. There is a lot involved. While there may be a lot of information here, you will want to study and connect with like-minded people. homedistiller.org has a lot of information. Including how to properly clean your still before you run it-important! How to build a gasket that you saw in the video above...and how to be safe.
[video=youtube;Z29Ci97ixRg]https://www.youtube.com/watch?v=Z29Ci97ixRg[/video]
Apparatus Construction:
Some random things you will need:
Solder - Lead free only. I use
http://www.homedepot.com/p/Oatey-H-20-5-Water-Soluble-Paste-Flux-Kit-with-Safe-Flo-Solder-506912/202515582#.UZ1SnJxsCcM Please stay clear of the electronics section when purchasing solder. The above kit comes with flux that will work just fine for copper to copper joining.
Sand paper or emery cloth. You can find emery cloth rolls in the soldering section at Homedepot etc.
Stainless steel wire brush. Again, you will find this in the soldering section.
Various drill bits, including 1/4inch
Propane Torch kit
Hack saw. Or some way to cut copper
***not needed, but a Dremal rotary tool is awesome to have.
Below is the basic parts list. The length of the still is your preference. I would not recommend anything less than 12inch long total length. For the length of tubes parts B,C,F,G you should review the video. Don't stress the measurements as much as pay attention to the mock-up. You make your copper tube cuts according to how the still is designed to be put together. Also on the video, I use a different connector that fits inside of the cap on the boiler top. Instead of using the part F.
A) 2 X 1"x.75" Copper reducer
B) 12" section of 3/4" copper tube
C) 10" section of 1" copper tube
D) 1 X 3/4"x1/2" Copper reducer
E) 1 X 1"x1/2" copper reducer
F) 3" section of 1" copper tube
G) 3" section of 1/2" copper tube
H) Roll of 1/4" soft copper tube you only need a few feet of this.
I) 1/4" to 1/4" compression connector brass lead free
Below is a very crude MSpaint schematic. This is not to scale, but it should do an ok job at helping you understand the apparatus. Read the copper parts list. I have assigned each a letter and have labeled to drawing and photos to help you make sense of the different construction aspects of this still.
In the drawing, I colored the center in pink. This is to represent the 3/4" copper pipe. It is also showing you the vapor path. Basically, you have the outer copper pipe, that is 1", and the inner copper pipe that is 3/4". Vapors rise up from the boiler, and when you are running water through the space between the 1" and 3/4" it chills this space. The vapors are forced back into liquid form. Beads-drops of liquid (distillate) roll down the inside walls of the 3/4 copper. Follow that down to the label "alcohol well". Look closely, you will see that the 1/2" copper tube extends up into the fitting. This creates a space, where alcohol will fill. As the distillate fills the well, it will run to the lowest point -- see the label 1/4" alcohol take-off. You will have a 1/4" line connected to the brass compression fitting. The line will lead to the collection jars so that you can reclaim the alcohol
to be reused; you MUST extend that 1/2" copper tube through the stop in the reducer
if you do not distillate will just drop back into the boiler.
I have some photos that are labeled that show the pieces
and a basic idea on how they come together. I am placing a photo of all the soldering joins that you have to create. As I edit, I will try to include informative resource links on proper ways to solder copper. When we get to the copper -- stainless joins, I am going to have to show you some specifics -- there are plumbers that do not know that you can solder stainless steel and copper together.
Here are the parts cut and ready for dry fitting. Soldering is next.
This is what you should end up with once pieces are dry fitted. Notice I have included the 1/4" soft copper attached. Please read the description on the photo that shows the soldering joints below.
Now dry fit the two parts of the still together.
Solder joints.
Some other notes on soldering this distiller.
Boiler construction:
As the name implies, a boiler is responsible for boiling. In this case, it must be large enough to meet your oil production needs. I decided to make a 2 gallon boiler for this project because I never plan to make more oil than what I can get from 6-8onces of bud at a time. That amount would require approximately 2 gallons of solvent (boiler capacity). You could, of course, make the boiler as large as you like. The only limiting factors would be the heat source that would be required to heat a very large boiler. For example, going larger than 5-7.5 gallons pushes the limits of small hotplate style electric burner (approx. 900-1000watts). It would take roughly 2-3 hours to boil off and reclaim the 2gallons of alcohol. 7.5 gallons on a small burner would take the better part of a day.
The concept is simple. Stainless steel pot, with a stainless steel salad bowl inverted on the top. You want a salad bowl so that you have plenty of head space for the vapors to accumulate before rising up and into the apparatus. The salad bowl makes a nice dome. So if you use the lid or something flat instead of the salad bowl, and you plan to fill the pot to capacity, you could get some coughing and choking as the boiling liquid rolls into the bottom of the still head.
I use inexpensive stock pots like this one I purchased from Big Lots here in the states:
At the end of the video, I show how to attach the copper cap to the stainless steel salad bowl. Watch it first and read below.
You can get this one on sale for under $10. I purchased the stainless steel bowl from Target. You have to match up a stock pot to the salad bowl so that the rim of the pot makes good contact to the rim of the bowl. You should be looking for a bowl and pot with nice flattened rims.
There really are only a couple things that must be done to construct this boiler:
1) Solder an inverted 1" copper cap fitting to the center top of the inverted salad bowl. And then drilling several 1/4" holes through the cap -- straight through the stainless steel salad bowl -- so that vapors can pass up and into the apparatus.
2) Create a PTFE gasket. Easily constructed gasket that is safe and provides a seal that can be re-used many times. Some people claim theirs have lasted over a year of consistent use.
****Optional and not covered. Review the video: Basic steps are, drill a 1/4" hole that a thermometer port can be pushed through. Cutting a length of 1/4" soft copper and solder/seal one end. Insert this thermometer port through the hole you created and solder it in place.****
You will need to purchase a special flux for this job. I use:
http://www.amazon.com/dp/B001HWE9A2/ref=biss_dp_t_asn
LA-CO M-A Liquid Stainless Steel Flux Liquid, 4 oz
This flux is essential (or a flux like the above). You cannot solder copper to stainless without it.
Some basic tips when soldering stainless steel to copper (watch the video -- toward the end).
This is a huge departure from what you know about soldering copper to copper. Stainless steel requires a large amount of cleaning. So you will need to sand and/or use a stainless steel brush, stainless steel wool to get ALL corrosion off the metal. You should never touch the stainless steel soldering area once cleaned. The oils from your fingers will prevent the solder from binding. You will also need to make certain that all sanding debris is brushed off the steel. If you used permanent marker to mark anything on the steel, it must be sanded off before you solder.
This flux is different. It is not a paste. It is a liquid acid based substance. You will use a clean brush to apply on both the stainless steel and the copper. Do not use any paste flux when joining copper to stainless.
Apply the flux where you want the solder to go. This is not a capillary situation. If prepared properly, the solder will pool and make a strong bond to the stainless. I will show you a photo of my stainless soldering and you will see that plenty of solder is used as it pools on the surface and binds to the copper.
[FONT=&]Never put the torch flame on the stainless. Heat the copper and let the heat transfer to the stainless steel. Stainless steel scorches at high heat, so keep that flame away. In actuality, the stainless is so thin that it heats up rather fast--even conducted from the copper. In fact, you can use a 100w soldering iron to push fuse solder on the surface of the stainless steel. Although not needed for this application, you can also use a soldering iron to solder two pieces of stainless together.[/FONT]
Additional information:
Cleaning your distiller
It is important to clean your distiller before you produce anything for consumption. You have spent hours sanding, scouring, fluxing, and soldering. You will notice sticky smelly/grimy residue coating every aspect of the still. I start out with a good scrubbing with soapy water. I use a bottle brush to try and loosen some of the caked on crud before I tackle the two step cleaning process.
The application of this apparatus (to produce oil) is in someways a backward concept -vs- running this as a traditional alcohol still. Meaning, when we make alcohol for consumption we are concerned about the product being clean...the alcohol. When we are using it to make THC oil, we are concerned that not only the alcohol remain clean for multiple uses, but that what is left behind in the boiler doesn't contain contaminating residues. Imagine that old flux melting off and dripping down into your concentrate, YUCK! So, we need to do an extra good job cleaning your newly created still. It is a two step process:
1) Vinegar cleaning run: Once you have done a soapy water scrubbing and have given your distiller a good rinse, fill your boiler about 75% capacity using equal parts vinegar and water. Assemble your still as you would a normal run and crank up the heat. Allow the hot vinegar vapors to blast the grime, grit, and oxidation. Collect the distilling vinegar as you would your alcohol and dump it out. One thing to note, your flow will be reduced since vinegar/water has a high boiling point...when compared to alcohol. I am only saying this because it may discourage you a bit; distilling 95.5% alcohol is a much faster process.
This is the vinegar run on the still in the video. Looks a bit different because I have a cold finger for additional cooling, not needed in our application. You can see that I turned off the cooling. Vinegar vapors are blasting out of the top of the still head. I ran it like this for a bit, so I could expose even the top part of the still to the cleaning vapors.
2) Sacrificial alcohol run: Although vinegar does a good job of cleaning, you will need to make sure you expose your still to hot alcohol vapors to dissolve the things that are more soluble in alcohol. You can use old wine, booze, or you could make your own with sugar, nutrients, and yeast (ferment your own wash). It does feel wasteful, but you must make certain that the still and boiler are clean. Everything you collect from this run must be discarded.
Once you have done this cleaning, most people will do it again in several months/year. The one thing about using the still to produce oil is that the inside gets a bit sticky...for obvious reasons. Just keep an eye on things. If it looks like it is getting grimy and sticky...just run some clean alcohol through it. Since the still processes high ABV alcohol, they do not need much cleaning just a rinsing between jobs.
How to make a PTFE gasket:
You noticed the Teflon gasket in the video. This is not my design. I am going to refer you to homedistiller.org forum discussion on the topic. It is a simple concept. It is cardboard that you wrap with plumber's Teflon tape several layers. If done correctly, it can last dozens of runs. It is important that you do not use corrugated cardboard -- it contains glues etc. Use fiber-compressed cardboard, like the stuff cereal boxes are made out of -- you will have to find some without printing on it. Follow this link:
http://homedistiller.org/forum/viewtopic.php?f=62&t=24199
If you have experience running stills, you will probably know that one strategy the old moonshiners would use to seal up their still (in place of a gasket) is flour past. The concept being that when the hot vapors hit the sticky flour paste, it will steam-cook-expand and seal the still. This works wonderful for producing alcohol, but I don't think it is reasonable for this application. Moonshiners do not have to worry if a bit of flour paste melts/falls into their boiler. They are only concerned about what is coming out of the condenser. However, when we concentrate our oil we do not want to contaminate it with cooked flour. So flour-paste is a no-no.
