Now, we put the lid on it and fill it with very very clean butane. The teflon tube lets me know when the cannabis is covered, you will likely be viewing the liquid level gage listed in the parts list. Im using the refrigerant recovery pump to expedite the transfer, using what is called a push pull technique, routinely used in refrigeration work. The tank is called a recovery tank and is special ($70) It has two ports, one leads to the bottom (liquid) and one the top (vapor).Once filled the cannabis is allowed to "steep" for some period of time. I have yet to decide how long is best, this run I steeped for 1 hour, probably too long. The oil I got on this demo run was a bit dark. I would steep for 10 minutes or so the first run, get a lower yeild clearer oil, and then do a second run with the same pot, but steep perhaps an hour.
I got this refrigerant recovery pump at a local pawn shop for $100, it wasn’t working. I bought a refurb kit for it for $150 and spent several hours fixing, taking apart, and cleaning it. Works like new now for $250. These pumps are on ebay both new/used/and refurbished, but if you get a used one, expect to take it apart and clean it out and I would put in a refurb kit. These pumps are made so that it is easy to refurb/clean/disassemble, it’s common maintenance for them.
Some details, its not as complicated as it looks, im not good at being concise.--
on each of the two ports of each vessel, I have put a ball valve that is part of a short 3 inch hose, listed in parts list. this is your valve for each port and has the fittings built on. so you need 4 of them, they come 3 to a set so you have to buy 6 from grainger, 2 spares
before putting butane in the steep vessel, you pull a hard vacuum on it. this all doesnt work as well if there is air in the system. you hook the suction port of the pump to the vapor port of the steep vessel, hook a hose to the liquid port of the tank and connect to the liquid port of the steep vessel, leave the tank valve closed but open both ball valves, pull a vacuum till the gage on the pump shows a good vacuum, this evacuates both hoses and the vessel, close the ball valve on the steep vessel. the pumps output is just to the environment for pulling air vacuums.
the "push pull" technique is used to move the liquid butane. The suction port of the pump is still on the vapor port of the "steep vessel" , the liquid port of the steep vessel is still on the liquid port of the tank. put a hose on the output of the pump, but dont hook it up to the tank yet, it will hook to the vapor port of the tank. open ball valve on liquid port of vessel, then open the liquid valve on the tank. the vacuum in the vessel will pull some liquid butane into the vessel. it will equilibrate in 2 minutes or so. then turn the pump on, briefly and slowly open the ball valve to the vapor port of the vessel that is hooked to the suction port of the pump and you can also manipulate the valve on the pump that opens the suction. some butane will be pulled throught he pump, and displace the air that is in the pump and in the pumps condenser, you will see some butane come out of the hose that is hooked to the output port of the pump, then shut the ballvalve that is connected to the vapor port of the vessel. now you have displaced the air, and can hook hook the free hose up to the vapor port of the tank,
you can leave the pump running, but it will shut itself off if it overpressures.
so now you end up, pump on, all valves open, and very quickly the vessel will fill with liquid butane, you must turn things off when the liquid level is where you want, basically filling the vessel 75% or so, or just over the top of the cannabis.
shut all valves for now, and steep 10 minutes first run, one hour second run. (edit add- I steep 1 minute first run 3 minutes second run now and get almost as much oil out and its lighter in color)
the blue knob on the pump opens the suction port. this leads to the vapor port of the steep vessel, a 3 foot hose to a short hose/ballvalve assemble.
the red knob on the pump is the output to the recovery tank vapor port.
the red knob on the tank is the liquid port, in this picture, I have put a filter/dryer inline. I dont know if this is needed, but it is listed in the parts, this filter dryer has short ends that can accept a 3/8 inch compression fitting, that i had to end up putting to 3/8 copper and then soldering (rigging nonstandard) the male flare fittings. room to adapt here. in refrigeration you get a slow buildup of water and it screws things up, so Im going to dry it with each run this way.
the center knob on the pump is the purge knob. when completed with certain steps, you turn this knob to purge, it puts the internal condenser on the suction side of the pump, but for vapor recovery it is on the pressure side. by putting it on the suction side, you can get all the liquid butane out of the condenser and put it in the tank when you are through. Important and in the pump instructions anyway.