After some weeks of planning and construction, I'm excited to reveal this excellent device... the Filament Vaporizer! The idea was to make a vaporizer which would deliver just exactly the energy needed to the smallest, highest purity sample of material.
After I came up with the idea I did extensive research online and found only one other person who had proposed something similar: a Dr. LungLife, who wrote an article in the May 1989 issue of High Times regarding his 'filament vaporizer'.
Below is quoted the particular section:
So I started by converting my cannabis into honey oil, using nonpolar pentane-hexane solvent extraction. When that was complete I had a dark brownish, sticky resin free of plant material.
The concept of a filament vaporizer is that the filament of a low-voltage bulb can be used to deliver a precise, geometrically small surface which can be heated to the exact temperature for vaporization by resistive heating.
I used a low-voltage bulb because line-voltage (120V) lamps use long, very thin and delicate filaments (higher resistance), which are totally unsuitable for such a project. The lamp used costs about $5 at a local lighting shop; this eBay seller has them for $2.05 US each.
Two 0.51-ohm 5W power resistors are used in parallel to regulate the filament voltage. The exact series resistance is 0.255 ohms for a 100W 12V quartz bulb.
The bulb is broken first. It is put into a ziploc back, sealed, then a hammer is used to crack the quartz glass. Sometimes the filament will be destroyed, but if done carefully a 50-75% yield should be expected. The leftover quartz still attached is carefully cracked off with needlenose pliers until just the base quartz is left. Then it is plugged into the white ceramic base.
Environmental friendliness was a key aspect of the design. For powering the filament, a rechargeable, recyclable NiCAD D cell which provides 1.2V was used. A NiMH AA cell was found insufficient, due to rapid charge depletion and concommitant current reduction. For powering the illumination LED, two 1.2V NiMH AA cells are used.
Note: Do not use alkaline cells for replicating this project. They are unsuitable for these reasons:
The revolutionary aspect of this design is that because we are using highly refined honey oil (or hash oil), a drop can be applied to the filament and vaporized with only one or two watts of power. This avoids problems associated with current vaporizer designs: they use a 'sledgehammer' approach which requires huge energy input to deal with poor delivery via conduction (BC vaporizer-style heating elements), and excessive plant material (both conduction and convection designs).
By eliminating the plant material entirely, the concentrated resin can be heated precisely with a vanishingly small dose of energy. This means instead of breathing hot air (which irritates the entire respiratory tract), you can breath cool air saturated with vapor.
I've been using this unit for a few days already and it is a dream come true!
A drop of oil is spread on the filament, and a quick flip of the power switch makes it instantly 'soak in' to the filament. The top is screwed on, and the power switch thrown again. In about 3-4 seconds there is a thick stream of white vapors coming off the filament (looks GREAT in a dark room illuminated by the small white LED).
The black tape on the bottom of the jar (which is on TOP during use), is peeled back to reveal a breathing hole, which is used to inhale the vapors. When not inhaling, the tape is put back on.
The next revision will remove the switch on the bottom and put a smaller, double-throw switch on the side of the red lid.
Safety Notes
-------------
Thermal safety: the resistors warm up during use, but not to above body temperature. The D cell doesn't warm up at all. Toxic vapors are a concern, so every component was carefully tested. The filament itself is pre-oxidized tungsten alloy, nonreactive. The quartz support structure is also non-reactive, as is the ceramic base it plugs into.
The vapors are essentially 'cold' due to the high energy efficiency, so reaction with the plastic container or componentry is not a concern.
Costs
------
Unit construction cost is about $15-20 using easily available parts. Rechargeable NiCd batteries (NiMH have double the capacity but have two problems: first, double the charge loss due to leakage, and inability to provide sustained high-current) are used, they should last 500 charge cycles, with about 1 charge cycle per 3-4 sessions (tested).
The bulb/filament has been through 5 sessions already, and still works great. It should last for 10-15, maybe more. Cost to replace: $5 (less if bought in quantity on eBay).
These costs are minimal compared to the time and loss of lung capacity due to inhaling smoke, which is totally unnecessary. I'll be revising the design and preparing for possible commerical production, so suggestions are welcomed.
After I came up with the idea I did extensive research online and found only one other person who had proposed something similar: a Dr. LungLife, who wrote an article in the May 1989 issue of High Times regarding his 'filament vaporizer'.
Below is quoted the particular section:
"Why vaporize THC oil?" asked Dr. Lunglife. "Chemical analysis has shown that a cigarette made of raw marijuana contains at least as much tar as an equal-sized cigarette made of tobacco. Although medical studies have not shown a connection to date, this fact does suggest [that] lung diseases such as cancer, emphysema, and bronchitis are possible consequences of heavy marijuana smoking." With vaporization, Dr. Lunglife explained, the essential THC oil is heated just enough to melt the active ingredients and transform them into smokeless vapor. If there’s no fire, smoke, or combustion, he concluded, there are no cancer-causing gases or tar.
Dr. Lunglife advocated a two-step process: First, he made concentrated black oil from raw cannabis flowers, thus eliminating the plant material in stage one. He then brushed the oil onto the filament of a small light bulb, which would be momentarily heated to complete the vaporization process. Seven months later, in the December 1989 issue, Dr. Lunglife published instructions ("Dr. Lunglife Invents a Better Vaporizer") on how to build an improved version that included a dome cover and had the capability to vaporize raw plant material.
Dr. Lunglife advocated a two-step process: First, he made concentrated black oil from raw cannabis flowers, thus eliminating the plant material in stage one. He then brushed the oil onto the filament of a small light bulb, which would be momentarily heated to complete the vaporization process. Seven months later, in the December 1989 issue, Dr. Lunglife published instructions ("Dr. Lunglife Invents a Better Vaporizer") on how to build an improved version that included a dome cover and had the capability to vaporize raw plant material.
So I started by converting my cannabis into honey oil, using nonpolar pentane-hexane solvent extraction. When that was complete I had a dark brownish, sticky resin free of plant material.
The concept of a filament vaporizer is that the filament of a low-voltage bulb can be used to deliver a precise, geometrically small surface which can be heated to the exact temperature for vaporization by resistive heating.
I used a low-voltage bulb because line-voltage (120V) lamps use long, very thin and delicate filaments (higher resistance), which are totally unsuitable for such a project. The lamp used costs about $5 at a local lighting shop; this eBay seller has them for $2.05 US each.
Two 0.51-ohm 5W power resistors are used in parallel to regulate the filament voltage. The exact series resistance is 0.255 ohms for a 100W 12V quartz bulb.
The bulb is broken first. It is put into a ziploc back, sealed, then a hammer is used to crack the quartz glass. Sometimes the filament will be destroyed, but if done carefully a 50-75% yield should be expected. The leftover quartz still attached is carefully cracked off with needlenose pliers until just the base quartz is left. Then it is plugged into the white ceramic base.
Environmental friendliness was a key aspect of the design. For powering the filament, a rechargeable, recyclable NiCAD D cell which provides 1.2V was used. A NiMH AA cell was found insufficient, due to rapid charge depletion and concommitant current reduction. For powering the illumination LED, two 1.2V NiMH AA cells are used.
Note: Do not use alkaline cells for replicating this project. They are unsuitable for these reasons:
▪ They cannot sustain the heavy current which flows through the filament.
▪ Disposal of non-rechargeable battteries presents environmental problems, so they ought to be discouraged.
▪ Unless the values of the two resistors are changed, the filament will overheat and burn the material (1.5V instead of 1.2V).
▪ Alkalines can't give anywhere near their rated capacity at high currents (ie. this application).
▪ Disposal of non-rechargeable battteries presents environmental problems, so they ought to be discouraged.
▪ Unless the values of the two resistors are changed, the filament will overheat and burn the material (1.5V instead of 1.2V).
▪ Alkalines can't give anywhere near their rated capacity at high currents (ie. this application).
The revolutionary aspect of this design is that because we are using highly refined honey oil (or hash oil), a drop can be applied to the filament and vaporized with only one or two watts of power. This avoids problems associated with current vaporizer designs: they use a 'sledgehammer' approach which requires huge energy input to deal with poor delivery via conduction (BC vaporizer-style heating elements), and excessive plant material (both conduction and convection designs).
By eliminating the plant material entirely, the concentrated resin can be heated precisely with a vanishingly small dose of energy. This means instead of breathing hot air (which irritates the entire respiratory tract), you can breath cool air saturated with vapor.
I've been using this unit for a few days already and it is a dream come true!
A drop of oil is spread on the filament, and a quick flip of the power switch makes it instantly 'soak in' to the filament. The top is screwed on, and the power switch thrown again. In about 3-4 seconds there is a thick stream of white vapors coming off the filament (looks GREAT in a dark room illuminated by the small white LED).
The black tape on the bottom of the jar (which is on TOP during use), is peeled back to reveal a breathing hole, which is used to inhale the vapors. When not inhaling, the tape is put back on.
The next revision will remove the switch on the bottom and put a smaller, double-throw switch on the side of the red lid.
Safety Notes
-------------
Thermal safety: the resistors warm up during use, but not to above body temperature. The D cell doesn't warm up at all. Toxic vapors are a concern, so every component was carefully tested. The filament itself is pre-oxidized tungsten alloy, nonreactive. The quartz support structure is also non-reactive, as is the ceramic base it plugs into.
The vapors are essentially 'cold' due to the high energy efficiency, so reaction with the plastic container or componentry is not a concern.
Costs
------
Unit construction cost is about $15-20 using easily available parts. Rechargeable NiCd batteries (NiMH have double the capacity but have two problems: first, double the charge loss due to leakage, and inability to provide sustained high-current) are used, they should last 500 charge cycles, with about 1 charge cycle per 3-4 sessions (tested).
The bulb/filament has been through 5 sessions already, and still works great. It should last for 10-15, maybe more. Cost to replace: $5 (less if bought in quantity on eBay).
These costs are minimal compared to the time and loss of lung capacity due to inhaling smoke, which is totally unnecessary. I'll be revising the design and preparing for possible commerical production, so suggestions are welcomed.