-------------------------------------------------------------------------- PFM1 - Pocket Sized Flame Thrower First Published by Information Unlimited Transcribed to the electronic media by Thallion of WUFO MCMXCIV. --------------------------------------------------------------------------- The following plans show how to construct a hand-held device intended for burning out insect nests such as wasps, ant hills, cocoons, maggots, tent caterpillars, gypsy moths etc. It may also be used to ignite rubbish piles, brush, leaves etc. This device like many with similar use and capability can be a dangerous weapon in the wrong hands. It should not be assembled unless the builder is thoroughly aware of the hazards involved. Range of this device is dependent on the chemical and the nozzle heads used. Usually a tight stream can have a range in excess of 20 inches, (similar to a toy water pistol) while a wide vaporous stream may only be effective up to five inches, but can create a virtual wall of fire and flame. *DANGER* A wind or stiff breeze blowing towards the user can produce disastrous results with the stream being in the form of a mist. Example of fuel for the device can be the highly flammable diethyl ether. This is often used for starting stubborn gas engines and is extremely hazardous both to the user and his surroundings. Ether has a low flash temperature and is highly explosive and flammable. Theory of Operation: REF FIG 1, 2, 3, 4 [See GIFs (POCFLAM1-4.GIF)] ------------------------------------------------------------------- Construction is shown as a pistol configuration with fuel source (FUC1) being placed in the handle (HA1). The electronic ignition (PSHK10) [Schematics in GIF 5] along with the battery is housed in the rear of the barrel (BR1). When (AA1) actuator arm activates (S1) contact along with the valve on the fuel source (FUC1) the fuel now spews out of nozzle (NOZ1). (S1) energizes the ignitor and a spark discharge at electrodes (EL1,2) ignites the fuel stream. The mechanical parts are indicated on a separate sheet [Found as GIF 1-4] and are those used for our laboratory prototype. Rather than explain the particular pieces we will describe their function instead so that the builder may use his own ingenuity in his implementation when constructing various configurations of the device. FUC1 - The fuel can may be a fresh can of the appropriate size depending on the builder's desires. We used a [number missing] oz can of WD40 available through your local hardware store. *DANGER* We must warn the builder of the hazards involved using WD40 or other similar chemicals. Certain low flash point solvents and fuels must be treated with caution! Fig 1 [= GIF 1] shows a reusable can fitted with a pressure valve for recharging. For maximum results a freon gas must be used as propellant, as compressed air will not liquefy at the low pressures used. CO1 - Small piece of copper soldered to can as shown in Fig 1, 2, 3 [= GIF 1-2-3] for switch contact abutting screw and spring combination. AA1 - Actuation arm can be any suitable insulating material that can be easily worked as shown in Fig 2 [= GIF 2]. We used a plastic electronic tuning tool and fabricated it as required. CA1, 2 - Shims so that FUC1 can will fit into appropriate enclosure. May use layers of glass fiber tape etc. to allow a snug fit. SPR1 - Small spring and screw/nut combination for contacting CO1 copper abutment. We used a spring found inside a ballpoint pen. BLK1 - PVC head block must be insulating material and snugly fit into BR1 barrel. We used a block of PVC drilled and tapped for nozzle screw and plastic tube TUB1 from fuel can. NOZ1 - Nozzle screw 6-32 x 1/4" soft metal for drilling a 0.05 hole lengthwise. The metal face protects the plastic head block from the flame. HA1 - Handle appropriate of plastic and metal tubing. We used a 2" OD plastic pipe with 1/4" wall. BR1 - Main enclosure, same material as handle. Select for easy fabrication. ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³ MECHANICAL PARTS LIST ³ ÃÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´ ³ Note: These are the materials we used for the lab prototype - ³ ³ You may use your own ingenuity. ³ ÃÄÄÄÄÄÄÄÄÂÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´ ³ Part ³Qt.³ Description ³ ÃÄÄÄÄÄÄÄÄÅÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´ ³ FUC1 ³ 1 ³ Fuel can (see text, Fig1) ³ ³ CV1 ³ 1 ³ Check valve for pressurizing - Also obtain removal tool ³ ³ ³ ³ for insert. Use tire type or mating fittings to charging ³ ³ ³ ³ supply, such as sir hose etc. ³ ³ CO1 ³ 1 ³ Copper contact plate - small piece of thin copper ³ ³ CA1,2 ³ 2 ³ 1-1/2" Plastic caps ³ ³ AA1 ³ 1 ³ Plastic actuator arm - use tuning wand or equivalent ³ ³ SPR1 ³ 1 ³ Small spring from ballpoint pen or equivalent ³ ³ SW1/NU1³ 1 ³ 4-40 x 3/4" Screw and nut ³ ³ LUG1 ³ 1 ³ Small solder lug ³ ³ WR1 ³ 1 ³ #24 Hook up wire ³ ³ WR2 ³ 1 ³ #18 Buss wire for spark gap electrodes EL1,2 ³ ³ BLK1 ³ 1 ³ PVC block 3/4 x 1 x 1-1/4" Fabricated per text Fig3 ³ ³ NOZ1 ³ 1 ³ 6-32 x 1/4 Aluminum or brass screw. Fabricated per text ³ ³ ³ ³ as shown in Fig3 ³ ³ HA1 ³ 1 ³ Handle ³ ³ BR1 ³ 1 ³ Enclosure ³ ³ BK1 ³ 1 ³ Bracket ³ ³ SW2 ³ 1 ³ Screw ³ ÃÄÄÄÄÄÄÄÄÁÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´ ³ *Reference* US Patent # 4.220.443 ³ ÀÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ PART 2: The electronic ignition (PSHK10) ---------------------------------------- Circuit Description: A high frequency self oscillating inverter circuit comprised of switching transistor (Q1) and step up transformer (T1) produces a high voltage high frequency at the secondary winding. This high voltage AC is rectified by diode (D2) and charges up storage capacitor (C3 or C4) thru current limiting resistor (R4). When this voltage charges up to breakdown potential of SIDAC (SID1), the energy stored in the capacitors is "dumped" into the primary of high voltage pulse transformer (T2) producing a high voltage pulse at the output terminal. A charging circuit consisting of current limit resistor (R1) and rectifier diode (D1) allows external charging of battery (B1) when NiCad or other rechargeables are used. The oscillator circuit utilizes a winding on T1 to produce the necessary positive feedback to the base of Q1 to sustain oscillation. Resistor R2 initiates Q1 turn on while resistor R3 and C2 controls the base current and operating point. Test unit as per the following: ------------------------------- A Position bare end of ground return lead (GRD RTN) so as to allow a 1/2" to 3/4" air gap between output pin of T2. B Connect 10V (8 AA NiCads at 1.25 volt each) to battery. C Note with S1 open you should note a fast pulsing action producing a mild bluish discharge. This can cause a very mild electrical shock and could be safely used within reason as a prank etc. D Note with S1 closed a thick slow pulsing discharge. This can produce a painful shock and is intended for use against animals etc. For use in this Pocket Flame Thrower, you could exclude S1, and put a permanent electrical lead there so that it is always set to "On", thus always producing a better spark. E Current draw with unit properly operating should be approximately 250 mA. F Check power tabs of both Q1 and SID1. These should be cool to warm to the touch. Are they really hot, then something is wrong. G You may verify proper operation using a oscilloscope noting the waveshapes as shown in [GIF 5]. Note: Input is shown operated with 8 NiCad cells in series for a total of 10 VDC. Unit however reliably operates within 6-14 VDC. If the circuit does not oscillate, try reversing one of the windings connections on the primary windings on T1. ÚÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ¿ ³ (See POCFLAM5.GIF) PSHK1 - PARTS LIST ³ ÃÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ´ ³ R1 ³ 100 ohm 1/4 watt resistor ³ ³ R2 ³ 4.7 Kohm 1/4 watt resistor ³ ³ R3 ³ 470 ohm 1/4 watt resistor ³ ³ R4 ³ 2 x 47 Kohm 1 watt in parallel for approx. 24 Kohm. ³ ³ C1 ³ 10 MFD 16volt Electrolytic Capacitor ³ ³ C2 ³ 0.047 MFD 25volt Paper Capacitor ³ ³ C3 ³ 3.9 MFD 350volt Paper Capacitor ³ ³ C4 ³ 0.47 MFD 250volt Polyester Capacitor ³ ³ D1 ³ 1N4001 50volt Diode ³ ³ D2 ³ 1N4007 1KV Diode ³ ³ Q1 ³ MJE3055T NPN Power Transistor (Any 3055 will do) ³ ³ SID1 ³ SIDACTOR K3000 FL 300 volts ³ ³ T1 ³ Self wound ferrite transformer Prim: 2x8T Sec: 1x350T ³ ³ T2 ³ 25KV pulse transformer ³ ³ (S1) ³ (Small SPST slider switch) ³ ³ J1 ³ 3.5mm Jack for recharger ³ ³ CL1 ³ Battery Clip ³ ³ PB1 ³ Perfboard 3-1/4 x 1-1/4 ³ ³ WR1 ³ #24 Vinyl hook up wire ³ ÀÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÙ