7600 uF 400 VDC, max surge 475 VDC
½ * C * V² = Joules
½ * 7600exp(-6) * 400² = 608 Joules

The TWR site in Manhattan Beach Californa sponsors a traditional Swap Meet on the last Saturday of each month, which features all matter of sellers ranging from ham radio to computer products, old and new.  My 608 Joules capacitors cost $8 for singles or $7 each for quantities over 4.  Not so much as the swap meet, but the one gentleman amongst a great number of sellers sells these caps. Another gentleman sells photocaps by the bucket full for less than .50 cents each. His motto is, "The bigger the pile, the bigger the smile."  Expanding my stock count beyond my 14 of these capacitors is ridiculous.

All (-) negative terminals are electrically bolted together by screws and linkers.  A linker is made from soldering a ring connecter to each end of 2 parallel strips of 12 AWG solid copper wire.  The natural golden-brown color of the copper wire is hidden under a layer of solder.
12 AWG copper wire is wound by hand around a steel rod, which also is the projectile source material.  This arrangement achieves very close, 0.5 mm, projectile - coil coupling.  A few layers of tape around the rod prevents tight fitting.  Generaly, coils undergo a strong contraction force during circuit discharge.  However, these coils retain a constant coupling because cyanoacrylate super-bonder adhesive is applied to each layer, raging from 4 to 10.  The terminals are terminated with either ring connectors or 12 AWG stranded wire with ring connectors.

 * 12 AWG solid wire
 * Super-bonder adhesive
 * Spade connectors
 * Ring connectors
 * 12 AWG stranded wire
These simple electrical contacts reduces the component count down to a current limiting resistor.  Not only good for a quick test of an SCR switched system, but also they serve good as a quick and simple means of control.  Unlike optical detection, the drawback is that the projectile's surface must be conductive, precluding the use of oil lubrication.

3  This detector was designed for mobility.  Fitting flush between the rails of the coil mount, the detector may be repositioned at different distances from the coil entrance.  A variable position eases the tunning of the capacitor bank pulse widths.  Constructed from 3 parts: base, riser,and tube.  Base formed from 4 strips of square wooden dowl.  Riser formed from 1 strip of dowl and any number of plywood strips for fine tunning if needed, a.k.a. shims.  Tube is formed from 1/2 " PVC pipe affixed with music wire and a 2 pin header.
     Usage: 7-Day CG Cannon

2   This detector was designed for limited space.  The spring wire is glued directly onto the exit end of a coil. 
     Usage: ACG 188, ACG 375

1   The housing is a wooden dowel sized to match coil diameter.  The four linear gouges excepts two V-shaped metal springs.  The metal was procured from mechanical ink pens.  This design is better suited for blunt projectiles.
     Usage: Many multiple stage systems.

 * Wooden dowels: round, square
 * PVC tubing 1/2 " diameter
 * Music wire 0.015 - 0.025 " diameter
 * Current limit resistor for SCR gate drive
The housing is a wooden dowel sized to match coil diameter.   Two wholes are drilled: one across the diameter to except LEDs, the other through the plane surface to except the projectile. This whole is 25% larger than projectile to allow for a slight mismatch with coil breach.

 * Wooden dowel
 * IR-LED       
 * IR-phototransistor
 * Bias resistors
 * Comparator
 * Vref resistors
Voltage Charger-Tripler
Lengthy charge time is a thing of the past thanks be to this AC powered 510VDC generator. In fact, very long charging times was one of the main reasons I halted my coilgun project way back in 1997. Now, I have to be carefull when charging capacitors because even with 2.4KJ the charge time is within 2 seconds. This is why a charge regulator was designed.


* Capacitors (3) 330V @ 600uF
* Diodes (4) 1000V @ 6 A rms, 80 A surge
* Relay (1 or 2) 120VAC @ 40 A

The diodes are placed anti-parallel across each coil.  This arrangement protects  both the capacitor and the silicon switch from the induced high reverse voltage (back emf) when the coil current has ceased by snubbing the emf down to (-.7v).  For my arrangement, 2 diodes in parallel caused 1 to sublimate, and of course  the associated Boom sound is included.  Actually the sound is more like

Diodes 1000V @ 6 A rms, 80 A surge
* Ring connectors
The terminal block is the intermediate connection between coils, switches, diodes, and capacitors.  Placed in series, I have 16 strips total to share for future 6 coils.
* 8 strip terminal block rated 30A (2)
* Fastening scews.
Glueing 2 wood dowels to a wood slap makes for straight alignment of multiple coils.  Each coil is fastened down with tightly wrapped masking tape.  Any detetors or sensors are insterted between each coil stage and may be easily adjusted because the simi-perment masking tape may be removed/added as needed.

Barrel less Coils
So far I have no need for a barrel.

* Wood slab 1/4" x 1 1/2" x  25"
* Wood Dowel round or square 3/8" x 25" (2)
The target mount was made to limit the number of scew hole manifestations in my table.  Now only two screws are used to fasten this mount to a table.  Logically of course, all scew secured targets are fastened to the mount.  The mount's entrance jig holds layers of sheet metal.  Because sheet metal is highly resilient yet bends fairly easy under high pressure, the aperture of this jig must be small to prevent the bending of the sheet metal to where it slips away from its housing.  The main housing is just one long wood slab cut into three even sections of 8".

* Wood slab 1/2" x 5 1/2" x 24"
* Screws
* BYOPCSM (bring your own potato, can, and sheet metal)
Voltage Charging-Parallel
   Though the capacitors appear as one bank by their close proximity, they are electrically isolated into 4 individual banks of common ground and share a common voltage charger.  The diode's function is to permit each capacitor to charge while not being influence by the potential of another capacitor.  The same is true in either idle or discharge mode.  No capacitor leaks into another, no capacitor knows the existance of another.  Simply said, TO EACH ITS OWN.
   During charging, the capacitor of least voltage charges first because its respective diode is the first to be biased.  Biased diodes are diodes turned on because the potential difference from anode to cathode exceeds a V(threshold)  > 0.5v.  The non charging banks have the cathode voltage of its respective diodes greater than its anodes; hence the diode is turned off.  These banks remain non charging until the voltage of the charging bank rises to equal the next V(threshold) whatever it may be.  Simply said, LEAST FULL FILLS FIRST.
   In the beginning, man was clue less and hasty.  The gift of high voltage rendered him giddy and proud.  Then the sudden existence of division distorted all elation into perplexity.  After a great head scratching, exhaustion from facial expressions, and pile of exfoliation festered from his nail biting, man stud to his feat and said, "Aha I will charge each capacitor one at a time".  All was well for a while until man's natural idiosyncrasy of haste spawned visions of less time.  Less time to charge,   less physical motion needed for charging, the search for such things brought about bafflement.  The usual brain storming ensued until charging by relay had came through.  This implementation did reduced the number of physical movements inherent to manual wire swapping.  However, the problem of time remained.  Fed up with the time problem and replacing burned out relays, man decided to reach deep into his mind to find that which is sublime. 


* Diodes (4) 1000V @ 6 A rms, 80 A surge

Voltage Charging-Regulator
The charge regulator charges a capacitor to a preset voltage after which the regulator releases power from the AC controlling relay.  This regulator is controlled manually with a normally opened push button switch so that one may cease charging before the preset level is reached.  The regulator's main function is to prevent 450VDC max capacitors from charging to 510VDC max off the AC powered Voltage Tripler.

* Comparator  LM339
* 5V regulator   LM7805
* NPN transistor 2n3904
* Voltage divider resistors 470K, 4.7k
* Potentiometer for reference voltage 1K
* Anti parallel protecting diode.
* N.O. push button switch

Source Energy

Potential :  2,432 Joules
Capacitor: 400v @ 7600 uF, QTY 4
     Bank 1: 400v + 400v = 800v @ 3600 uF
     Bank 2: 400v + 400v = 800v @ 3600 uF


Projectile # 1

25 Joules Kinetic Energy
Velocity =  43.8 meters/second
Weight   =  26 grams
Length   =  7.1 centimeters

800v 40A-rms 520A-surge
Brand  =  Teccor
QTY     =  6 in parallel for Banks 1, 2
Cost    =  $2.70 each

Hand wound 6 layered
26 turns of 12 AWG wire
Equipped with terminal mounts

Cyanoacrylate Adhesive

This is a generic bottle used to hold together coils, coil mounts, screw bolts, and SCRs. Basically, this is the liquid form of duct tape.

7600 uF 400 VDC,  max. surge 475 VDC

½  *  C  *  V²                       =         Joules
½  *  7600exp(-6)  *  400²  =   608 Joules

1000 V 6 Amperes
4 in parallel

* Ring connectors

Voltage Tripler

Input    = 120 vAC (rms)
Output = 510 vDC(peek)

* Diodes 1000V 6A (4)
* Capacitors 330V 600 uF (3)
* Relay
The Penetrator

Steep pointed angle designed for the purpose of penetrating steel sheet metal and food cans.
Coil #3
Hand wound 4 layered 18 turns of 12 AWG solid copper wire.  Equipped with 12 AWG stranded speaker wire and ring connectors.