| Project completion & status: | ||
| Power supply: | 0% | The power supply is currently being conceptualized. |
| Charging Circuit: | 0% | The charging circuit is currently being conceptualized. |
| Capacitor Bank: | 45% | One of the two banks is mostly complete, and awaits only a bleeder resistor. |
| Firing Circuit: | 0% | The firing circuit is being completely ignored at the moment. |
| Coil: | 0% | The coil is being completely ignored at the moment. |
| Barrel & Projectiles: | 25% | The first shot(s) will use a stock barrel. |
| Protection Circuit: | 0% | The protection circuit is being completely ignored at the moment. |
| Overall: | 10% | The gun is pretty much a cap bank and some copper tubes right now. |
Thanks to the guys over at the .HV Passport Forums, I now have a new direction for the charging circuit. It involves using a variac to power a MOT (Microwave Oven Transformer) to the voltage I require, and then rectifying that to charge the capacitor bank. Since I already have a microwave which is headed for the trash heap, but has a perfectly good MOT inside, I only need to acquire the variac, and then the power supply component of this project will be complete! Below is a revised rough schematic of the power supply and charging systems.
Even more laziness and lack of spare time has prevented the project from being near completion by now. Instead, it is essentially what it was at last update, except I've ordered some resistors for the charging circuit and safety bleeding of the cap bank. Currently I'm researching exactly how I intend on getting 450VDC out of pretty much anything, and right now, a 450VAC->110VAC step-down transformer wired in reverse seems to be my best (a.k.a. cheapest) option, although weighing in at roughly $100 new. That, a circuit breaker, and a line cord would likely take care of my power supply objective, moving me towards my next goal, the charging circuit. Right now, that looks like it's going to be a single-phase full-wave bridge rectifier hooked up to the transformer's primary, along with the resistor I ordered earlier, and most likely some form of switching mechanism in there somewhere. After that, I conquer the coil. That should only take me the next year or two at this rate. Below is a rough schematic of the power supply and charging systems.
A decent amount of laziness has prevented the project from being more than twice as complete as it is now. Presently, I have created two copper buss bars which link the 10x1100uF/450VDC capacitors together in parallel. I'm currently constructing the buss bars for the 8x2200uF/450VDC capacitors, also to be banked in parallel. I had wound a coil of 16 AWG magnet wire around one of the copper tubes in order to perform some preliminary tests, but as it turns out, I didn't secure the coil with anything, so it just sort of unraveled after time. A thin layer of epoxy will likely hold the final coil together, supposing the epoxy has no detrimental effect to the insulating coating on the magnet wire. Ultimately, the wire should be of a lower gauge as well. Below are some pictures of the first (and completed!) capacitor bank.
Note: These snapshots have been taken in infrared mode with my new Panasonic PV-DV602 digital camcorder. The capacitors are actually blue. Expect better pictures when I move more of this stuff out of my bedroom and into a semi-dedicated area in my garage.