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Zenador

Thu Nov 13 2008, 03:46PM

Registered Member #1733 Joined: Thu Oct 02 2008, 03:17PM
Location: Hamilton, ON, Canada
Posts: 100

I have 2 issues.

One, I have parts I don't know what to do with.

2x vacuum motors. different sizes, both work. Came out of working but useless stick vacuums. One could go into a
sucker SGTC, the other I dunno.

A 5kV 30mA NST. I could build another table-top TC, but I have one already. Suggestions?

Small MOT. Don't have the ratings off-hand.

20 camera flash boards. I've made 2 coils from these parts, but I have 20 intact boards left. I was thinking a cap-bank charger for a mini rail gun and mini coil gun. I'll still have many boards left over.

My second issue is my girlfriend (whom I live with) needs a hobby. She gets bored easily, really easily if I'm in my workshop working on stuff. She feigns interest in my coils and other projects, so I have no hope in getting her to help. What do your wives/girlfriends do while you are working on your projects or otherwise engaged?

Thanks guys...

Z

Arcstarter

Thu Nov 13 2008, 06:32PM

Registered Member #1225 Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253

Well, you could make a sgtc with that single mot believe it or not. Just use a voltage quadrupler and a properly sized high voltage choke.

Steve connor has a very nice one, as seen above.

The thing i really like about those DC tesla coils is that the power supply is constant voltage, so you can use an asynchronous rotary spark gap without losing power output because it will not fire at too low voltages just because the cap is right in the middle of the sinewave. So, you can accurately change the bps without worrying about losing performance.

20 of those camera flash caps would make a decent coilgun or railgun or w/e you may use it for. I would highly recommend that you use bleeder/balancer resistors and make a few strings of a few caps and put the strings in parallel. Because that will have the same energy storage and all in parallel, but at a higher voltage. The higher the voltage compared to capacitance, the faster the discharge will be. You of course want a fast discharge, because if the discharge takes to long on a coilgun, the projectile will first be accelerated, and then decelerated, so you will lose efficiency with slower discharge. Also be sure to use a protection diode across the capacitor bank to stop a reverse charge, which is caused by the inductance in the wires, and coil. Of course, as you probably know, you do not want a polarized cap to be charged with wrong polarity.

Also, for just a bit of fun, you can use one of the vacuum motors for a rsg :P. A high speed one, but of course it would take time and money because you would need reduction gears/pulleys.

aonomus

Fri Nov 14 2008, 12:35AM

Registered Member #1497 Joined: Thu May 22 2008, 05:24AM
Location: Toronto, Ontario, Canada
Posts: 801

Do what the mythbusters did and build a miniature hovercraft...

Or alternatively stick your lips into the spinning fan blades inside the vacuum motor.

teslacoolguy

Fri Nov 14 2008, 01:31AM

Registered Member #1107 Joined: Thu Nov 08 2007, 10:09PM
Location:
Posts: 792

aonomus wrote ...

Or alternatively stick your lips into the spinning fan blades inside the vacuum motor.

That is an excellent idea*

* not responsible for any lip damage that could result

Backyard Skunkworks

Fri Nov 14 2008, 02:05AM

Registered Member #1262 Joined: Fri Jan 25 2008, 05:22AM
Location: Maryland, USA
Posts: 451

You can make a fun gun with vacuum cleaner motors. Use them to drive two wheels that almost touch, and then feed a projectile in.

Arcstarter

Fri Nov 14 2008, 03:45AM

Registered Member #1225 Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253

Backyard Skunkworks wrote ...

You can make a fun gun with vacuum cleaner motors. Use them to drive two wheels that almost touch, and then feed a projectile in.

That would be fun, but dont you think 15k rpm would be a little much for anything that has good enough friction? If you where going to use something like a small metal rod, you would need like a pneumatic tire to allow for it to 'warp' to the size of the projectile, while still tight around it, and you would need to use something like rubber for plenty of friction. So what i propose is just use a large pneumatic tire and use some reduction gears, because, i mean come on, at 15k rpm there would be a s$#t ton of centrifugal force and it would rip it apart.

Steve Conner

Fri Nov 14 2008, 11:42AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Something like this...

Zenador

Fri Nov 14 2008, 02:20PM

Registered Member #1733 Joined: Thu Oct 02 2008, 03:17PM
Location: Hamilton, ON, Canada
Posts: 100

Thanks guys.. I watched the MythBusters where Adam put his lip to the blade. Not intelligent. The projectile launcher is nothing more than a mini batting cage ball launcher.

I think I figured out my next project. I was reading up on Plasma speakers. Looks so sweet. The only thing in my way at the moment is finishing my boost converter. I etched a board for it, mounted everything, hooked it up, and proceeded to fry 2 inductors. The first was too small and fried instantly, the second one lasted about 5 minutes before smoking.

While the smoke is disappointing, it's still kind of neat. And small inductors make a really neat sound when they blow.

Z

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