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Interesting "lifter" observation

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Antonio

Sun Jul 20 2008, 12:06AM

Registered Member #834 Joined: Tue Jun 12 2007, 10:57PM
Location: Brazil
Posts: 644

When I started to experiment with "lifters", I made one with the lower "skirt" glued only to the outer side of the triangular frame:

The lifter worked, but producing a lot of ozone and with a strange tendency for vibration of the corona wires. I initially imagined that the vibration could be due to some ripple in the power supply voltage, but with a better regulated power supply the problem continued the same:

I tried to make a larger lifter, but obtained only incontrollable wire vibration.
I then tried to fold the skirt over the upper beams, as recommended in several sites in the Internet. This made some improvement in the performance, but the most visible effect was complete elimination of the vibration. The ozone generation was also much reduced.
I made a triangular and a square lifter with the same wire length, and they performed identically, even simultaneously, powered in parallel from the same power supply:

It appears then that the vibration was caused by an interaction between the corona wires and the corona produced at the edges of the skirt.
The structures of these lifters were made with strips (~5 mm) of plastic foil folded as "L" beams.

Avi

Sun Jul 20 2008, 01:33AM

Registered Member #580 Joined: Mon Mar 12 2007, 03:17PM
Location: Melbourne, Australia
Posts: 410

maybe more corona is produced the closer it moves to the foil, thus possibly reducing the voltage (more current), which would decrease the electrostatic attraction, which would cause it to move back up and repeat?

Antonio

Sun Jul 20 2008, 02:31AM

Registered Member #834 Joined: Tue Jun 12 2007, 10:57PM
Location: Brazil
Posts: 644

If the moderator thinks that "lifters" are pseudoscience, he can remove the thread. But that the thing works, by corona wind of course, it works. And is a very nice HV experiment.

Conundrum

Sun Jul 20 2008, 04:05PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4062

I have some experiments planned with conductive fabric sent to me as a free sample... looks like its about 1/3 the weight of foil.

regards -A

Steve Conner

Sun Jul 20 2008, 08:25PM

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

Discussion of lifters is fine as long as nobody claims that they work by any mechanism other than corona wind!

Andyman

Sun Jul 20 2008, 09:42PM

Registered Member #1083 Joined: Mon Oct 29 2007, 06:16PM
Location: Upland, California
Posts: 256

Corona wind? Everyone knows it's anti-gravity!!

*sarcasm*

aonomus

Sun Jul 20 2008, 11:25PM

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

I just watched the mythbusters episode that had the lifter, the wires do seem to vibrate a fair bit, perhaps its due to electrostatic attraction until corronal discharge reduces the attraction until it snaps back under tension. I think that Avi nailed it, cause under vacuum a lifter doesn't work and in the episode the brief shot showed no wire vibration...

Steve Conner

Mon Jul 21 2008, 12:08PM

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

Andyman, don't even mention those words. It makes the forum show up in google searches for a***-g****** and attracts the wrong kind of membership. :P

Antonio

Mon Jul 21 2008, 11:17PM

Registered Member #834 Joined: Tue Jun 12 2007, 10:57PM
Location: Brazil
Posts: 644

While adjusting a "lifter" power supply today, I noticed that one of the corona wire sections of the lifter was vibrating. The reason was easily found as a bend in the ground wire, producing negative corona at a height by the center of the lower skirt. Straightening the wire eliminated the vibration. I then taped a thin wire ring to one side of the skirt to see what would happen. As expected, the corona wire above it passed to vibrate intensely.
A video:

Herr Zapp

Sat Jul 26 2008, 01:59AM

Registered Member #480 Joined: Thu Jul 06 2006, 07:08PM
Location: North America
Posts: 644

Antonio -

Please clarify what material you used for the "frame" of your lifters. I'm not sure what "plastic foil" is; it sounds like metallized plastic, but that can't be right, unless you used different materials for the triangular frame and the vertical members supporting the corona wires.

Also, for the skirt material, has anyone used metallized polypropylene film unrolled from a large rolled-film capacitor? This should be much thinner and lighter than any aluminum foil?

Regards,
Herr Zapp

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