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Re: Van de Graaff prime season; where is everybody?

 

Work and , building a new r/c fixed wing drone with a planked wing design, iNAV autopilot .? ? Hopefully I will build a new 5ft VanDeGraaff generator in time for Halloween 2020

On Feb 21, 2020 9:51 PM, "Hank Riley via Groups.Io" <n1ltv@...> wrote:
This is the peak of the season for electrostatics with low humidity and less competing outdoor activities.

Where is everybody?? Let's have a little noise on this group!? Be the first to post (other than moi) in 2020 before the month ends.

Van de Graaff prime season; where is everybody?

 

This is the peak of the season for electrostatics with low humidity and less competing outdoor activities.

Where is everybody?? Let's have a little noise on this group!? Be the first to post (other than moi) in 2020 before the month ends.
Fun way to puncture a plastic bottle

 


click on gif to enlarge.
Cute way to light a bulb.

 

??
Re: Lightning screen and HV AC power supply

 

The screen works fine with any HV supply. The danger is that a back fire through the transformer will destroy the transformer.
Building an auto coil HV supply is the safest and cheapest way to go, and a single auto coil system will work.
Doug


On Thu, Nov 28, 2019 at 4:16 PM Hank Riley via Groups.Io <n1ltv=[email protected]> wrote:

?
Doug has made a new video showing all the parts of the system and then showing it running.??
?
Sparks are very impressive from the dual coils fed by 60 Hz.? That's a 12 inch diameter screen.
?
I wonder how the screen would work with a neon sign transformer or an oil burner transformer.? I'm guessing the gap would have to be smaller for the oil burner transformers I've used (in a Jacob's Ladder.)
Re: Lightning screen and HV AC power supply

 

Doug has made a new video showing all the parts of the system and then showing it running.??

Sparks are very impressive from the dual coils fed by 60 Hz.? That's a 12 inch diameter screen.

I wonder how the screen would work with a neon sign transformer or an oil burner transformer.? I'm guessing the gap would have to be smaller for the oil burner transformers I've used (in a Jacob's Ladder.)
Re: For sale by Doug

 
Edited

Thanks Doug, I appreciate the help.
Cheers
Rod

On Wed, Nov 27, 2019 at 6:09 AM Douglas Johnson <doug379306@...> wrote:
This is the cheapest, but, very effective HV supply. Light dimmer $5.00, Motor run cap. free to very cheap, auto coil from salvage yard. $??
I have drawings?for a single coil or dual coil unit.I like to run my screen through a HV filter to keep any {back fires} away from the mains.
If anything is unclear please feel free to contact me.
Values of the motor run caps is nominal.?
Doug
Re: Lightning screen and HV AC power supply

 

Hank,

The front plate is secured any way you can, but glue is fine.
As for the Auto coil HV supply,
I am not educated enough in electronic theory to understand how it works, but it does!

Also, I have 2 dual auto coil HV supplies [60KV] with all new components? I would sell for $70 plus shipping.
I would also build the HV filters, but would have to research prices of components to give a quote.
I can also fabricate?discs and pulleys?for Wimshurst machines.

Doug

On Tue, Nov 26, 2019 at 4:45 PM Hank? wrote:

Doug,
?
This feeding of an auto spark coil through a fairly large series cap with line voltage AC is new to me.
?
Is the basic idea to just eliminate the expense of a step-down transformer that would normally be used to drive the coil?
?
With the lightning screen, is the front plate glued on?
?
Hank
Lightning screen and HV AC power supply

 

Doug,

This feeding of an auto spark coil through a fairly large series cap with line voltage AC is new to me.

Is the basic idea to just eliminate the expense of a step-down transformer that would normally be used to drive the coil?

With the lightning screen, is the front plate glued on?

Hank
Re: For sale by Doug

 

This is the cheapest, but, very effective HV supply. Light dimmer $5.00, Motor run cap. free to very cheap, auto coil from salvage yard. $??
I have drawings?for a single coil or dual coil unit.I like to run my screen through a HV filter to keep any {back fires} away from the mains.
If anything is unclear please feel free to contact me.
Values of the motor run caps is nominal.?
Doug
image.png
image.png
image.png
Re: For sale by Doug

 

Sorry I so late getting to this, I had to first walk the dog, then make the best pasta sauce on the planet for my dear wife!?
The pics show the Lightning screen front and back, nothing more than a 12" glass plate with conductive material on the back with conductive tape overlapping the rim. the front has a 6" disc in the center. So what you have is a "flat plate " capacitor.
Next email, Cheap power supply and optional but recommended?HV Filter.
Doug

Lightning screen back.JPG
Lightning screen front.JPG
Play safe.JPG

Re: For sale by Doug

 

Doug's Lightning Screen factoids will be shared here, not just in private email.? That's what these lists are for.

I liked those screens, too, and the electrostatic motors like I haven't seen elsewhere.
Re: For sale by Doug

 

Hi Ross, I'll do all the spects. tomorrow and also send some picts.
Doug
Re: For sale by Doug

 

Hi, I¡¯m a member of the VDG Group, and also curious about details of your Lightning Screen. Its like the Strickfaden devices in old movies.

Regards

Ross

arlunan@...

?
Re: For sale by Doug

 

Hi Rod, I'll get on it tomorrow and give you all the info on the lightning screen. It is getting late here.
Doug

On Mon, Nov 25, 2019 at 6:25 PM Rod <rodon685@...> wrote:

I agree Doug, shipping to Australia would cost me both my arms and a few toes I expect.? Can you please send me some information on the Lightning screen, I'd like to replicate it.
Cheers
Rod
Re: For sale by Doug

 

I agree Doug, shipping to Australia would cost me both my arms and a few toes I expect.? Can you please send me some information on the Lightning screen, I'd like to replicate it.
Cheers
Rod

On Mon, Nov 25, 2019 at 11:39 PM Douglas Johnson <doug379306@...> wrote:
Hi Rod,

Yes I am pretty much interested in clearing out some stuff. The big problem I see is shipping cost and the buyer being able to reassemble correctly if the device must be disassembled for shipping. I will try to come up with what I have invested in anything you are interested in and a shipping cost.

I am in Grand Rapids Michigan

Thank You
Doug

On Mon, Nov 25, 2019 at 6:13 AM Rod <rodon685@...> wrote:
What part of the world are you in Doug, I have a Van de Graaff but your Lightning screens and bipolar coils interest me greatly.
Cheers
Rod
Re: For sale by Doug

 

Hi Rod,

Yes I am pretty much interested in clearing out some stuff. The big problem I see is shipping cost and the buyer being able to reassemble correctly if the device must be disassembled for shipping. I will try to come up with what I have invested in anything you are interested in and a shipping cost.

I am in Grand Rapids Michigan

Thank You
Doug

On Mon, Nov 25, 2019 at 6:13 AM Rod <rodon685@...> wrote:

What part of the world are you in Doug, I have a Van de Graaff but your Lightning screens and bipolar coils interest me greatly.
Cheers
Rod
Re: For sale by Doug

 

What part of the world are you in Doug, I have a Van de Graaff but your Lightning screens and bipolar coils interest me greatly.
Cheers
Rod

On Mon, Nov 25, 2019 at 5:24 PM Douglas Johnson <doug379306@...> wrote:
All of these are for sale at modest prices.

?

?

Doug
For sale by Doug

 

All of these are for sale at modest prices.

?

?

Doug
Re: Project VDG machine

 

Russ,

You're welcome.? The work hasn't ended because the photos and files are lacking the contributors' names and dates of submission for one thing.?

Another effort is the old message base which was always planned to be the last component to appear.? There is recent activity that promises to provide a method to effect a good recreation of the message base.

The high performing VDG with capacitor was first published in the February 1958 Science and Mechanics by the master himself, Harold P. Strand.? The Craft Print Project (almost the same as the article) is available at the website:



The pictures I posted do have a bit of a fake look to them, but you can see that similar thick sparks of that great length are in the pictures for the article.??

In another post I'll tell about making a series of real nice and proper pictures that are unobtainium at the moment.? That picture (one is a blowup of the other) was taken by an onlooker when I did a demonstration before a small club (not of VDG people).

Hank
__________________________________________


On Wednesday, November 20, 2019, 05:20:58 PM EST, russ edmonds <russ.edmonds@...> wrote:

Thanks Hank for migrating this group to groups.io I bet that was a lot of work!

The top terminal is really appealing because my prized Harold Strand 5 inch diameter terminal machine??
?
?
produces about 12 inch monster sparks, and this SF one is quite considerably bigger at 8 inches.

A 12 inch spark from 5 inch diameter VDG is amazing, when I first saw that photo I thought it was fake!?

By Harold Strand machine do you mean that it was originally built and owned by Harold P. Strand ? If so, how on Earth did you get it ?
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