Vandegraff Generator
ChemTechLabs, Fri Feb 10 2006, 07:53AMAs i'm currently becoming interested with High Voltage things !lol , I thought that a good first project would be a Vandegraff generator. I'm thinking of using 1 or dual vacuum cleaner motors for the TYPE of motor, and possibly something very large and round such as a globe with a layer of Aluminum Tape on the inside and out for the sphere on top. Does anybody have any suggestions for what other kinds of materials may be more effective for either the motor, sphere, or belt? Or just any helpful suggestions at all would be appreciated.
Re: Vandegraff Generator
Carbon_Rod, Fri Feb 10 2006, 08:03AM
I have seen the Mini demo:
Rubber band + glass fuse + hobby drive + Pop can + PVC pipe...
And the huge spun brass spheres with plexi and teflon parts...
What voltages or diameter are you thinking about?
:D
Carbon_Rod, Fri Feb 10 2006, 08:03AM
I have seen the Mini demo:
Rubber band + glass fuse + hobby drive + Pop can + PVC pipe...
And the huge spun brass spheres with plexi and teflon parts...
What voltages or diameter are you thinking about?
:D
Re: Vandegraff Generator
Dr. Shark, Fri Feb 10 2006, 09:44AM
Unless you are very good at building mechanical things, I would not suggest a VDG as a first HV project. If you have got just a tiny bit of electronics experience, there are lots of easier ways to get some sparks.
For the VDG you could use IKEA salad bowls for the sphere (at least everyone seems to to that), and an exercise belt thingie you get from fitness shops. A vacuum cleaner motor seems a bit overkill for first experimentation, you will need a sound mechanical structure for that. I'd rather suggest a power drill for that.
However, the usual frist HV project would be a Flyback transformer from an old TV or monitor, that can very easily be driven with two MOSFET transistors and a handfull of passive components.
Dr. Shark, Fri Feb 10 2006, 09:44AM
Unless you are very good at building mechanical things, I would not suggest a VDG as a first HV project. If you have got just a tiny bit of electronics experience, there are lots of easier ways to get some sparks.
For the VDG you could use IKEA salad bowls for the sphere (at least everyone seems to to that), and an exercise belt thingie you get from fitness shops. A vacuum cleaner motor seems a bit overkill for first experimentation, you will need a sound mechanical structure for that. I'd rather suggest a power drill for that.
However, the usual frist HV project would be a Flyback transformer from an old TV or monitor, that can very easily be driven with two MOSFET transistors and a handfull of passive components.
Re: Vandegraff Generator
HV Enthusiast, Fri Feb 10 2006, 12:53PM
Thats not true at all. Building a VDG is extremely easy. A small motor, several rubber bands, and a toilet bowl float is usually enough for beginners.
And as always, www.sciencefirst.com of NY sells VDG parts for anything you can think of. Just go their website and download some of the VDG manuals. In the back of the manuals, they have the parts lists. So you can get very nice belts, pulleys, motors, 14" and 16" aluminum spheres (oblates), etc... So those hard to find or make parts can be purchased here. At the least, i would recommend the belt they sell.
Dan
HV Enthusiast, Fri Feb 10 2006, 12:53PM
wrote ...
Unless you are very good at building mechanical things, I would not suggest a VDG as a first HV project. If you have got just a tiny bit of electronics experience, there are lots of easier ways to get some sparks.
Unless you are very good at building mechanical things, I would not suggest a VDG as a first HV project. If you have got just a tiny bit of electronics experience, there are lots of easier ways to get some sparks.
Thats not true at all. Building a VDG is extremely easy. A small motor, several rubber bands, and a toilet bowl float is usually enough for beginners.
And as always, www.sciencefirst.com of NY sells VDG parts for anything you can think of. Just go their website and download some of the VDG manuals. In the back of the manuals, they have the parts lists. So you can get very nice belts, pulleys, motors, 14" and 16" aluminum spheres (oblates), etc... So those hard to find or make parts can be purchased here. At the least, i would recommend the belt they sell.
Dan
Re: Vandegraff Generator
Michael W., Fri Feb 10 2006, 03:26PM
The problem with a VDG is you need a motor with a large amount of torc and kick to get the belt moving unless you want to start it by hand....Thats where the Vacuum motor comes in.
Michael W., Fri Feb 10 2006, 03:26PM
The problem with a VDG is you need a motor with a large amount of torc and kick to get the belt moving unless you want to start it by hand....Thats where the Vacuum motor comes in.
Re: Vandegraff Generator
Marko, Fri Feb 10 2006, 03:29PM
Just use standard DC or AC motor big enough.
Some reductors are good idea too if they are implemented in motor..
Marko, Fri Feb 10 2006, 03:29PM
Just use standard DC or AC motor big enough.
Some reductors are good idea too if they are implemented in motor..
Re: Vandegraff Generator
FaLLoUT, Thu Feb 23 2006, 09:37PM
im trying to build a wimshursts machine which is much easier to maintain and build VDG are hard to maintain...i think u should build a wimshursts machine first and it will function as good as VDG
FaLLoUT, Thu Feb 23 2006, 09:37PM
im trying to build a wimshursts machine which is much easier to maintain and build VDG are hard to maintain...i think u should build a wimshursts machine first and it will function as good as VDG
Re: Vandegraff Generator
Omicron, Sun Feb 26 2006, 07:15PM
start with some thing safe and work your way up!
Omicron, Sun Feb 26 2006, 07:15PM
start with some thing safe and work your way up!
Re: Vandegraff Generator
vasil, Sun Feb 26 2006, 07:44PM
Build a Bonetti machine, it is simple and it has much more current capability, because the used surface of the discs is not limited at the metalic sectors. Yes, it is not self starting as a Whimshurst, but this can resolved easily using a PVC pipe, electrised by friction, put near the disc, opposite to the neutraliser, while you turn the crank.
vasil, Sun Feb 26 2006, 07:44PM
Build a Bonetti machine, it is simple and it has much more current capability, because the used surface of the discs is not limited at the metalic sectors. Yes, it is not self starting as a Whimshurst, but this can resolved easily using a PVC pipe, electrised by friction, put near the disc, opposite to the neutraliser, while you turn the crank.
Re: Vandegraff Generator
Kolas, Mon Feb 27 2006, 05:50AM
wow VDG- dangeous!!!?
heh unless you charge a large cap bank with one, i think its damn near impossible to be killed by a small VDG.
assuming it's not outputing over 100kv. (which is hard to accomplish such voltages(due to insualtion)
at those votlages, even a small topload could contain enouph joulege to hurt someone
never the less, use a grounded chicken stick to discharge it be fore touching and all that saftey stuff
but since most people get around 30kV
i think a VDG is a great place to start
kolas
Kolas, Mon Feb 27 2006, 05:50AM
wow VDG- dangeous!!!?
heh unless you charge a large cap bank with one, i think its damn near impossible to be killed by a small VDG.
assuming it's not outputing over 100kv. (which is hard to accomplish such voltages(due to insualtion)
at those votlages, even a small topload could contain enouph joulege to hurt someone
never the less, use a grounded chicken stick to discharge it be fore touching and all that saftey stuff
but since most people get around 30kV
i think a VDG is a great place to start
kolas
Re: Vandegraff Generator
cbfull, Tue Feb 28 2006, 01:34PM
A coulple things to watch out for if you decide to build a VDG:
Belts that are very elastic will severely limit how fast you can run the belt. They have a terrible tendency to come off the rollers, possibly causing damage to other parts. They also tend to oscillate inside the column, sometimes to the point of slapping which can create a grabbing effect.
As long as you have means of controlling the motor speed, you can avoid these problems by just slowing the motor down. Vacuum cleaner motors run ridiculously fast compared to induction motors.
Good luck!
cbfull, Tue Feb 28 2006, 01:34PM
A coulple things to watch out for if you decide to build a VDG:
Belts that are very elastic will severely limit how fast you can run the belt. They have a terrible tendency to come off the rollers, possibly causing damage to other parts. They also tend to oscillate inside the column, sometimes to the point of slapping which can create a grabbing effect.
As long as you have means of controlling the motor speed, you can avoid these problems by just slowing the motor down. Vacuum cleaner motors run ridiculously fast compared to induction motors.
Good luck!
Re: Vandegraff Generator
vasil, Tue Feb 28 2006, 05:17PM
If you use a collector electric motor, put it in an enclosure. The fine carbon powder from the carbon brushes can affect the dielectric properties of the belt.
vasil, Tue Feb 28 2006, 05:17PM
If you use a collector electric motor, put it in an enclosure. The fine carbon powder from the carbon brushes can affect the dielectric properties of the belt.
Re: Vandegraff Generator
ChemTechLabs, Fri Mar 03 2006, 05:16AM
well i'm most likely going to be using some kind of a rubber belt (any suggestions where i can get one for either cheap or free?
) and I WILL have a fan switch or some kind of acceleration control dial on it just in case a vacuum cleaner motor is in fact too powerful.
ChemTechLabs, Fri Mar 03 2006, 05:16AM
well i'm most likely going to be using some kind of a rubber belt (any suggestions where i can get one for either cheap or free?
) and I WILL have a fan switch or some kind of acceleration control dial on it just in case a vacuum cleaner motor is in fact too powerful.Re: Vandegraff Generator
Desmogod, Fri Mar 03 2006, 07:56AM
See if you can get hold of some theraband from a physio for the belt.
Might be a bit thin though.
Desmogod, Fri Mar 03 2006, 07:56AM
See if you can get hold of some theraband from a physio for the belt.
Might be a bit thin though.
Re: Vandegraff Generator
Part Scavenger, Tue Mar 07 2006, 02:34AM
Tips:
The faster the motor the better until you hit 5000 rpm IIRC from a book("Lightning Bolt Generators" - Lindsay publications). I used a belt sander as one pulley, the middle part of a bicycle wheel (pull out all the spokes, best top pulley around I know of). I used the liner out of the wheel for the belt and later part of the innertube, it worked pretty well. If I did it all over again, I'd find something a little less rubbery. Maybe a piece of treadmill? Work hard or your brushes, they were the limiting factor in the one I made. I read somewhere about someone using a "sprayer" to seed the VDG. This was a HV device that sprayed ions onto belt to be picked up at the top. Maybe then it doesn't classify as a VDG? Still neat though.
EDIT=> Another thought about a belt. See if you can get your local firestation to give you some old hose. There's a rubber liner inside that might work well, especially if you kept the canvas stuff on one side. Just a thought. We throw hose away all the time in the FD I am a part of. You can get it in many sizes too.
Part Scavenger, Tue Mar 07 2006, 02:34AM
Tips:
The faster the motor the better until you hit 5000 rpm IIRC from a book("Lightning Bolt Generators" - Lindsay publications). I used a belt sander as one pulley, the middle part of a bicycle wheel (pull out all the spokes, best top pulley around I know of). I used the liner out of the wheel for the belt and later part of the innertube, it worked pretty well. If I did it all over again, I'd find something a little less rubbery. Maybe a piece of treadmill? Work hard or your brushes, they were the limiting factor in the one I made. I read somewhere about someone using a "sprayer" to seed the VDG. This was a HV device that sprayed ions onto belt to be picked up at the top. Maybe then it doesn't classify as a VDG? Still neat though.
EDIT=> Another thought about a belt. See if you can get your local firestation to give you some old hose. There's a rubber liner inside that might work well, especially if you kept the canvas stuff on one side. Just a thought. We throw hose away all the time in the FD I am a part of. You can get it in many sizes too.
Re: Vandegraff Generator
Vaxian, Wed Apr 11 2007, 11:46AM
All very good information.
I have considered building a VDG for a while, this is all helpful to me also
Thganks, will keep reading this thread
Vaxian, Wed Apr 11 2007, 11:46AM
All very good information.
I have considered building a VDG for a while, this is all helpful to me also
Thganks, will keep reading this thread
Re: Vandegraff Generator
cbfull, Wed Apr 11 2007, 05:26PM
I can help you to solve some of the problems you will/might encounter if you like. I am "refurbishing" mine right now, but the basement is getting finished in a month or two so I can't get into any of my bigger projects at the moment.
For the belt, it will likely be easier if you make your own. There are two kinds of home-spliced (glued) belts that I am aware of that give excellent results. They both come from the same supplier, which is McMaster.com.
One of them is called "Vinyl-Laminated Nylon Fabric" (the thinnest), and the other is called "Coated Nylon Fabric" (also the thinnest). The nylon mesh backbone is very, very strong in both materials and will allow you to tighten your belt and crank up the speed (but not until it is ready!!!). The polymer coating is needed to keep the combs from neutralizing the charged roller, which is why your rollers cannot be the same material as the belt surface!
Hope this helps with your belt dilemma.
cbfull, Wed Apr 11 2007, 05:26PM
I can help you to solve some of the problems you will/might encounter if you like. I am "refurbishing" mine right now, but the basement is getting finished in a month or two so I can't get into any of my bigger projects at the moment.
For the belt, it will likely be easier if you make your own. There are two kinds of home-spliced (glued) belts that I am aware of that give excellent results. They both come from the same supplier, which is McMaster.com.
One of them is called "Vinyl-Laminated Nylon Fabric" (the thinnest), and the other is called "Coated Nylon Fabric" (also the thinnest). The nylon mesh backbone is very, very strong in both materials and will allow you to tighten your belt and crank up the speed (but not until it is ready!!!). The polymer coating is needed to keep the combs from neutralizing the charged roller, which is why your rollers cannot be the same material as the belt surface!
Hope this helps with your belt dilemma.
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