High Voltage Ballast Resistor and Inner Grid Help

This forum is for specialized infomation important to the construction and safe operation of the high voltage electrical supplies and related circuitry needed for fusor operation.
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Caine Ardayfio
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High Voltage Ballast Resistor and Inner Grid Help

Post by Caine Ardayfio » Mon Feb 12, 2018 2:14 pm

Hello Fusioneers,
I was wondering how I would go about finding a 200 kΩ 320 W wirewound ceramic high voltage ballast resistor for my fusion reactor. I've looked online and most ballast resistors are only 0.4-1.8 Ω, a minuscule fraction of what I need. If there are any alternatives to this amount of power in a ballast resistor, that'd be great. I also would like to know how one would find a 1.25” Diameter three-hoop spherical grid, made using 0.48 mm tungsten wire. I've primarily been using the materials that Kuba Anglin used in his youtube video, but I'm open to suggestions on different materials to use in my fusor as I don't want to be an exact-copy of the stuff other fusioneers have done.

Look in the description to find the materials I'm using.
https://www.youtube.com/watch?v=hrXIp1XA3wM&t=593s

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Dennis P Brown
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Re: High Voltage Ballast Resistor and Inner Grid Help

Post by Dennis P Brown » Mon Feb 12, 2018 6:42 pm

I got a fusor grade 300 watt wire wound ceramic resistor on e-bay. If one searches often, a usable unit often appears - don't be too specific and get a large number of hits to look over. Remember, they can be put in oil to improve their cooling so a lower wattage resistor can be then made acceptable.

I bent and wrapped a steel welding rod to make my system's coiled electrode but others here have posted methods to make titanium ones. Do a search for the previous month or two should get some results on this issue.

Caine Ardayfio
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Re: High Voltage Ballast Resistor and Inner Grid Help

Post by Caine Ardayfio » Mon Feb 12, 2018 7:02 pm

Thank You Dennis,
I'll try your advice on getting the resistor, but I do have another question. Is your advice on "I bent and wrapped a steel welding rod to make my system's coiled electrode but others here have posted methods to make titanium ones. Do a search for the previous month or two should get some results on this issue." for use with the inner grid, or is it used for the ceramic resistor?

Jon Rosenstiel
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Re: High Voltage Ballast Resistor and Inner Grid Help

Post by Jon Rosenstiel » Mon Feb 12, 2018 8:58 pm

As to fusor grid wire, I suspect Dennis meant tungsten, not titanium.

Jon Rosenstiel

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Dennis P Brown
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Re: High Voltage Ballast Resistor and Inner Grid Help

Post by Dennis P Brown » Tue Feb 13, 2018 10:59 am

Yes to referencing the grid, and I should have said tungsten - good catch.

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