Hi All,

I have done a BiTT of research, pun well intended.  If I may make a recommendation of something I will be trying with my replication... high perm material on the inner core is crucial, of course, but the outer core need not be this difficult.  One can set iron powder, iron filings, magnetite, etc in a resin, and cast the outer core around the wound inner core.  A drill press and/or grinder may be necessary to put the finish shape on it after the resin has set.

Cheers,
Twinbeard

Also: David confirmed to me the Nanoperm toroid he uses for the secondary is a Nanoperm M-416, not M-146 as mentioned in the PESN article.

I have them made here in Kearney Nebraska from L&S industries
4100 East 39th Street Kearney, NE 68847-3987
(308) 236-5853 you will want to talk to Jeff. the part is like 25 bucks you
will need two of them tho.

You can select your metal as well.
The tooling has been paid for... so just order it. no need to make it hard.

The M-416 with about 1000feet of 16awg wire will fit perfectly in the new part. "Like a glove."

You can select your metal as well.
The tooling has been paid for... so just order it. no need to make it hard.
Mav

QuoteI have done a BiTT of research, pun well intended.  If I may make a recommendation of something I will be trying with my replication... high perm material on the inner core is crucial, of course, but the outer core need not be this difficult.  One can set iron powder, iron filings, magnetite, etc in a resin, and cast the outer core around the wound inner core.  A drill press and/or grinder may be necessary to put the finish shape on it after the resin has set.

That's a great idea... have you confirmed that it works?  I'm just wondering out loud, because perhaps there might be something needed in terms resistivity (or lack thereof) in the material?   

Also what do you plan on using as a 'form' so you get a good shaped outer toroid?

Thanks,
Feynman

Hi,

You must be the inventor.  Nice work, and a pleasure to meet you.  I understand... you are making it totally easy for replication with essentially off the shelf parts, in the interest of exact replication and independent verification.  Very admirable.  You may find some interested parties here, however, for whom the expense or hassle in freight and customs may be burdensome. 

The permeability gradient between the two core materials is the critical factor here.  High permeability on the secondary (inner) core and low permeability on the primary (outer) core.  This is what prevents the flux induced in the secondary from returning to the primary.  The coils need to be tuned properly as well, of course, to reach optimal conditions, but there is a wider tuning band available in your device, I would propose, than in the BiTT, as respects the coils.

My recommendation as to casting is not so tough... some fiberglass or epoxy resin, and some powdered ferrous material.  It may make this project accessible to a wider group of people, and an improvement in terms of magnetic coupling between primary core and secondary windings may be achieved this way as well.

Just my $.02.

Cheers and well done!
Twinbeard

Quote from: Mavendex on March 22, 2011, 05:39:49 PM
I have them made here in Kearney Nebraska from L&S industries
4100 East 39th Street Kearney, NE 68847-3987
(308) 236-5853 you will want to talk to Jeff. the part is like 25 bucks you
will need two of them tho.

You can select your metal as well.
The tooling has been paid for... so just order it. no need to make it hard.

The M-416 with about 1000feet of 16awg wire will fit perfectly in the new part. "Like a glove."

You can select your metal as well.
The tooling has been paid for... so just order it. no need to make it hard.
Mav