RadioBanter - View Single Post

March 4th 06, 02:25 AM posted to rec.radio.amateur.homebrew

wrote:
Anyone have a guess as to the permeability of steel filled epoxy?

Was sort of wondering what would happen if one tried to make RF
inductor or transformer (torroid, etc) cores out of the stuff...

with care, it can even reproduce threads, so tuneable slugs might be
possible.

It's available as putty in tube form in many hardware stores, and as a
castable liquid from industrial supply catalogs - though obviously if
ordering something from a non-local supplier, it might as well be a
proper core from Amidon.

(and yes, I may go ahead and try it... soon as I get my workbench set
back up to the point where I could build something to measure the
results)

My guess (based on my attempts to make cores out of granulated ferrite
and epoxy) is that you will be doing well if you achieve a relative
permeability higher than 10. And that assumes that the iron is pure,
iron, or silicon iron, not steel.