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Message-ID: <020e01c6aa33$48617b80$0300a8c0@LAPTOP>
From: "Peter Martinez" <peter.martinez@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <009f01c6aa0e$aedf1f40$6501a8c0@eagles>
Date: Tue, 18 Jul 2006 06:27:45 -0000
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Subject: LF: Cutting toroids
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>From G3PLX:

J:

If the toroid in question is ferrite, i.e. a ceramic material, then forget 
about cutting it, especially if you want to be able to put the two halves 
back together again and still have a good magnetic path. The only way is to 
crack it, which you can usually do in a vice, with a steel rod (a nail) 
across the middle of one side and two bits of wood suporting the edges of 
the other side.  If you need the two halves to be precise, you can score 
along the intended break-line with a diamond or tungsten scribe like you do 
before cracking ceramic tiles in the same way.The cracked surfaces will not 
be flat but will mate perfectly.  You can then do your winding or threading 
on the separate halves and either clamp or glue them back together and get 
back to a pretty good magnetic circuit.

Iron dust toroids are made from an epoxy loaded with particles, and can be 
cut easily, but they won't crack cleanly like the ferrite ones.

73
Peter