I’m using vermiculite blocks for soldering, too. What I consider
to be its best characteristic in comparison to carbon blocks is,
that it has a plain surface, that stays plain, even if you’ve
used it for a long time.
If I’ve got to do some soldering where I’ve got to fix the
parts, I still use the carbon block. In some catalog I’ve seen
blocks made of ceramics, which have lots of tiny holes, to insert
needles for fixing the objects for soldering.
Another method for fixing wires to solder, is to make a pap of
dust of tripoli and a little water and put small drops of that
onto the right positioned wires. Let it dry. Now you can solder
without moving the wires. It’s kind of glueing the pieces onto
your soldering block. (hope it comes clear, what I’m trying to
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