Georgie, you get my vote for the most intrepid Orchidian out there.
But your difficulties could be many things. My drawplates do go
in.5mm increments - there's a .25 here and there. You need some big
stout pliers, if not official draw tongs. And you must use
lubrication - we use Vaseline. In tubing, it's easy to draw it, until
the edges meet, and then it gets really, really hard to draw - it's
like a 2mm wire, which is a lot to draw. I try to make it "perfect" -
so the edges meet at the size I want, then I give it one last pull,
for roundness. Trying to reduce the size IS difficult. Also, your
troubles could be related to the taper of the holes on the backside.
They need to be very smooth and even. I do congratulate you for
making a drawplate out of wood - realize that the forces involved
are extreme - it may have a fairly short life...
I must apologize - I replied to this before <above>- most of it
was (hopefully) useful. But I just pulled some wire, and my
recollection was wrong. It's a carbide drawplate from 2.8mm to
tiny, and the holes aren't.5 mm, they are.1mm steps - quite a
difference, and a couple are.05mm.