Info for a Newbie

Hi all,

I have finally recieved my mini mill. Now comes the fun part!
This is my first CNC conversion, and is looking like a decent
challenge! My plan is to build up as much as I can- the idea here is
to
get it together with a limited budget. Well, buying it all just
would not be fun, too! ;)
Also, I am in Japan, so shipping from anywhere of big stuff can
make
things not locally sourced expensive.

Right now i am looking for some suitable stepper motors. I have
recieved the plans for a bi-polar stepper driver and motherboard and
so
i guess this slightly limits me to 4,6 and 8 wire steppers- right?

Now, I`d sure like to know what the rule of thumb is for stepper
motor
size and possible gearing. My mill is of a similar size to the
minimills sold by harbourfreight etc- but it isn`t on the sieg
site...
I have no idea who made it- i got it through in importer here in
Japan,
but so far it is nice! Quite heavy castings and lots of sliding area
on
all the gibbs- plus the machining on them looks good enough to run
as
is with no re-work. It also has a wedge style gibbs setup as apposed
to
the setscrew type on my lathe, which I assume the seig mills have
too.
( it also has a second Z axis "plunge" of 50mm for drilling!)

Anyway, it has 2mm pitch achme threads on the X,Y and on the Z
(vertical) it has a 4mm. I am thinking I will need to do an (at
least)
1:2 on the vertical. I imagine the vertical will have 4X the torque
demand of the X,Y- so can I use a big toothbelt reduction to avoid
having to find a huge stepper?

Today, I found a single stepper that was a "23" hybrid unipolar.. 6
wire job for $10... but only one :( I didn`t buy it as I imagine I
want them all the same?

O.K, I have gone on quite long enough. <I am excited about this>
Sorry, but my wife just rolls
her eyes when i talk to her about it.

Stefan