ATM 14.5.I.S..........secondary

["natsp" <natsp@alltel.net>]

what size secondary do i need?
the focal legnth is 72 5/8" now that its
polished and partily parabolized.
i would like to make a secondary,
instead of buying one.
i was told they are hard to make strait
but i cant belive its much harder than grinding a parabol.
i want to make every part of the scope
from the internet and from scrap stuff.
at focal legnth the sun is about the size of a quarter.
ps: im looking for foucaults for dummiees,----instructions..
ive been reaserching a week
and still cant grasp it..
take care
stan