Sanity Check on Power Supply Capacitor Size

Sanity Check

Filter Capacitor Size for Power Supply based on:
C=(80,000*I)/V
Transformer (secondary tap) will be putting out (18V * 1.414=25.5V) with
8.3A*2=16.6A (since it is wired in parallel).
With these specs I get C=(80,000 * 16.666)/25.452=52,386 Microfarads.

So the filter capacitor size I need must be at least 52,386 Microfarads?
Is this calculated correctly? Boy, that seem high … does it not?

Back Ground info:

I am building a Power Supply to drive my stepper motors out of two Transformers
(http://www.surpluscenter.com/item.asp?UID=2005071308202974&catname=&qty=1&item=15-1176)
in wired in a Parallel circuit. My schematic is shown here:
http://www.pennswoods.net/~luke1027/PS_Schematic.jpg