This Kovarex system will supply you more Uranium than you may ever need.
Simply add 40 Uranium 235 to the left most centrifuge, move Uranium 238 to the top input however you like, and within about 1 hr you will be producing a lot of Uranium 235. of course you can add 120 Uranium 235 to each Centrifuge and it will start producing Uranium 235 right away.