I did alot research before I started veggin.
Read alot of people doing the Appleseed processing (heat and settle) method.
Some people that did the jean leg filtering (person I bought my truck did this method)
And those that Centrifuge
And anyone that did any of the first two then switched to centrifuge said it would have saved them a lot of money and time to start with a centrifuge. Gravity is one G my centrifuge 1350 G's
Initial start up is high but is cost effective in the long run.
I pour through a few barrel filters (600-200) from dudadiesel on ebay then i pump it to a settling barrel with a hard wired water heater element wired for 120v and another that is on an extension cord so i can use it else where when is gets cold.
I heat for about 3 hours about 180-200 deg f then let it settle for 24hours - 1 week (depends on free time) pump the top 3/4 of barrell to a gravity barrel.
Then it goes through a WVOdesigns inline heater (6 gallon water heater is best) into a centrifuge from Simple Centrifuge.
The only consumable I have is the a 2 micron Donaldson filter for my Vegistroke system on my f250. It needs only needs changed every 10-15k miles. Actually I just checked and its been 19k miles since my last change. The Veggistroke lets you know when the filter needs changed.
Harbor freight clear water pumps work if you keep it primed, Norther Tools are better quality and don't leak around the treads like HF sometimes do.
WVO Designs monster pump is AWESOME.
But if your handy get a m-55hv oil pump (generically refereed as a SBC oil pump) for a small block chey drill and tap some hose barbs and connect to a motor. They great if done right. here is a link
http://www.frybrid.com/forum/showthread.php?t=10978 but there are several people with their own versions.
If your heating the oil dont use plastic barrels, Steel barrels should be food grade that way they have the coating on the inside so you dont have to worry about poly buildup.
Then cleaner your oil is the better for your engine.
Gravity alone wont take out all the water. You need heat. I know a few that tried letting the oil set for 6 months in the sun in and the top 1/3 of the oil still didn't pass the HotPanTest.