Here's my stainless steel DIY hop stopper that I made for $10. It started it's life as a jumbo tea ball from Amazon.com
. I took a phillips screwdriver and forced a hole in the side of the SS screen and stretched it out until it was large enough to fit over my SS pickup tube. I also cut about 1.5" length off the side pickup tube, and cut some grooves into the end of the tube so that if the screen got pushed up against the end of the tube and some hops got sucked into the screen, the wort can still drain out thru the grooves.
I brewed an 11 gal batch of porter today that had 5oz of whole hops in it, and it filtered out everything with no trouble. I could drain with the valve fully open and there was no blockage or hops getting into the fermenter.
This paves the way for me to get a plate chiller now, since I don't have to worry about hops getting stuck in my pickup tube or in a plate chiller. I haven't tried it yet with pellet hops, but I think it would work OK with them too.
Took me about 5 minutes to create the hole in the screen, and 15 minutes to cut the grooves in the tube with a dremel. Don't waste $60 on a Blichman hop stopper - this will work just as well and is ridiculously easy to make.
5oz of leaf hops left in the kettle after the boil.
I just thought I'd update that I tested this hopstopper with pellet hops recently and it does not work quite as well. It would probably work fine with just a couple oz in a batch, but if you use a lot of hops it can plug the screen up. It works best with whole hops, which is primarily what I use since I buy in bulk from Freshops.com