We use a sifting table, that has a top layer of prob
1/8th wire then a second layer with 1/16th under it
as the table shakes the worms and larger unprocessed stuff rolls off the top and into a catch bin.

the cacoons and partially processed stuffs go to the bottom layer and stay there. the castings pass on
through and fall in the catch bin. We've been pulling out about 75-100 pounds every two weeks from now 30 bins.

Here's a partially finished project that might give some ideas for a screening device...

http://www.arkiegold.com/MultiMeshClassifier.html

The major thing I'm looking at as keeping from having 100% pure castings is the hair content of wastewater sludge in my pilot program. Not sure the worms will be able to handle it any if at all but surely gardeners will know hair is a good addition to the soil!

There is a huge difference between Vermicompost and Pure Worm Castings.

Clarification is needed for terminology used with the terms worm castings and vermicompost. The term "vermicompost" is used much like "compost". Most people have no idea of how it is going to perform until they use it. Vermicompost contains worm castings and other organic matter that has been partially or fully composted. Who knows how much pure worm castings are found in vermicompost? The amount of pure worm castings will vary from batch to batch and from one vermicomposting facility to another. Introducing a handful of redworms into a compost pile does not produce a good quality of vermicompost.

Our pure worm Black Castings™ are just that - Pure Worm Castings. There are no variables. Each bag, each month and each year consistently delivers high quality Black Castings.™

Quality in - quality out that is what we are all about.

Hi Rachael,

I don't know about the 100% guy--you'd have to do some pretty fancy screening and also use a blower to get 100%. And then there would still be some things in there that aren't castings.

I CAN tell you that you can come pretty close with Bruce Galle's 14 day method. Bruce is constantly experimenting and coming up with better ways to raise worms and produce castings. This is a method that he devised by using his knowledge and experience and a lot of trial and error. Actually, Bruce claims 100% too and, as I said, it's pretty close.

Bruce has a newsletter, blogs, forums, & etc. on his sites--lots of good info. He also sells worms and other products and I can testify that he makes it right if there is a question about whether he shipped the right quantity of worms.

Anyway, here's a link to his 14 day ebook and most of his other projects. It's $14.95 and worth every penny:
http://orderworms.com/Books_c14.htm

His method uses 5 gallon buckets. The pickles that delis put on every sandwich plate come in 5 gallon buckets and you can normally find a place that will give them to you. If you have to buy them, go to Firehouse Subs. They sell their (red) pickle buckets with lids for just $2.00. All the pickle buckets are 90 mil and food grade while the ones you buy at hardware stores or Wal-Mart are only 70 mil and who knows what grade.