In production since last week this TexasRedWorm Flow Through 2 has been a work in progress for several years. I have been looking at examples of flow through bins homemade and commercially available for some time. This latest design is the latest version predated by several prototypes. This latest evolution has been a success thus far. I ended up purchasing the metal racks from Costco for about $137. Easy to assemble and very sturdy, these were a great buy at a good price. I spent about $70 on hardware (nuts, bolts, screws, washers, 20′ of .25″ cable, and cable clamps). Key to a long lasting box built around the metal rack, were cypress 2×6’s from TexasDozer.com cut from my dad’s saw mill. Cypress will not rot and in it’s natural state (no chemicals used to preserve the wood) and will not leach out anything harmful to the worms or castings.
The cutting diamond bar was fabricated out of scrap and square tubing for the guides. This will be pulled with winches mounted to both sides of the rack to cut and harvest castings from the bin.
Two mason tubs purchased at Lowe’s for around $13 each rest on the bottom rack just below the flow through bin to catch castings. The bottom of the bin was lined with newspaper and worms and compost were added. We will let the worms go to work for several weeks feeding compost as needed. Over the next few weeks the newspaper will break down and the bin will be ready to harvest. For the initial harvest, remove by hand the newspaper from under the screen. Use the winch from one side to move the cutting bar across the bottom of the bin one time.
Texas Jumpers 
I live in SC and my question is: do you have problems with fire ants bothering the worms? I’ve been looking into tube composting rather than bin composting but fire ants are the one thing holding me back.
They haven’t been a problem for me, but you can use (food grade) diatomaceous earth sprinkled on top and kept dry it will not harm worms and get rid of insects and other bugs.
If you should encounter a fire ant assault sprinkle some (food grade) diatomaceous earth around the ants. Kept dry it will stick to bugs and create tiny cuts on their bodies and kill them off. It will not harm your worms.
Hi, I’m keen to build a worm farm similar to what you have here. do you have a materials list for it? is the diamond cutter moving along runners at the side of the bin? more details on this would be really helpful
thanks
bonnie
Any updates on how this bin performed? Any issues with the design and cutter bar? Do you have detailed plans for this?
The issue was too much air flow. The bottom layer would dry and cake up. The flow through might perform better in more humid climates, but for South Texas I didn’t like it. I think it can be a good solution just not my preference. I am now just using raised beds and 100 gallon stock tanks. I use my sifter to process castings.
Interesting about it getting too dry. I was looking at building one, so I might try to semi seal under the cutters of the unit to increase or reduce humidity in the collection area. Thanks for posting your build.