I had seen a similar concept using metal rods as well as had the bottom left wide open, allowing for variety of varmints to enter the system. I decided to build it keeping it simple so as about anyone could put it together.

One thing to keep in mind is many web sites state that the end product is worm castings in a continuous flow through system. The reality is that the end result is a vermicompost, a mix of some unfinished decaying organic matter and worm castings. While the worm castings by themselves are considered “Black Gold”, the vermicompost will do very well in many garden plants too or simply screen the mixture.

Many ask if you will lose many worms out of the bottom, no worries here. As with anything you will lose a few stragglers however the worms are consistently migrating upwards and should reproduce much quicker than your few lost worms coming through the bottom when you harvest your vermicompost.

Materials / Tools:

1 – 55 Gallon drum (one not previously used for chemicals)

1 – 2’ X 2’ piece of 3/8” plywood if your bin has not lid

4 – strips of 3/8* plywood or less, can be from lid scrap above.

1 – 12” X 8” – 1/8” or ¼” galvanized hardware cloth

4 – Short wood screws ~ ¾” to 1”

40’ – Weed whacker line

1 – Piece of approx. 80 grit sandpaper

1 – Reciprocating saw

1 – Phillips or flat head screwdriver… depending on your screws.

1 – Cutting tool for the galvanized hardware cloth.

1 – tape measure.

1 – drill

1 – 1/8” drill bit

The first thing to do is mark out a 12” wide  by 8” high opening on the bottom, 2 inches from the bottom of the drum.

Next center and mark out another opening 10” wide by 6” high inside the one you just made.

Cut out the smaller opening first as this will make it much easier. Once you cut the outer opening, save this piece.

I ran the weed whacker line from side to side as I noticed the structural strength was weekend from front to back once the opening on the bottom was cut. Hence locate and center mark your two sides two inches above the top of your cut opening on the bottom of the drum.

Now you will want to drill holes 1 1/2” on center. This does not mean going around the exterior and measuring 1 ½” all around as this will mess you up.

The simplest way to figure this task out is to drill your two centered side holes, measure 1 ½” to either side and drill those two out. Temporarily run the weed whacker line through all three holes on both sides, back and forth and snug up a little. Now you can reach inside and lay the tape measure over the three lines you ran and mark out 1 ½” in both directions on both sides of the bin. Be sure your marks are level before proceeding to drill them out. You can use your tape measure or if you have scrap wood around, use a precut piece as a template to the height from the bottom of the drum to the height of the holes to be drilled.

To run the weed whacker line tie a large knot on one end of the line and begin threading the line back and forth, starting at either the front or back of the drum. Once ran, proceed to reach inside the drum and start by pulling and placing tension on the lines to snug up, beginning where you first began to thread the line. Once complete, tie another knot on the other end to secure the tension on the weed whacker line and cut off excess.

Now you can cut your lid for the drum if your drum did not come with one out of the 3/8” plywood. Be sure to leave it a little larger than the drum top to over hang a little to prevent rain… from getting in should you be placing outside.

Under the lid, Drill 1/8” holes around the top of the drum spaced about 1 ½” apart.

You should have enough scrap from the plywood lid to cut four strips. Cut four pieces six inches long, two at 1 ½” wide and two at 2” wide.

Use the sandpaper to sand the edges of your fron lower door panel to remove the burs left behind when cutting the door.

Trim the galvanized hardware cloth to fit by being a little smaller than the outer edge of the saved piece from your bottom opening cut. Use the wider strips on the front and the narrower strips on the back of each side to hold the galvanized hardware cloth in place, securing with the four screws. Line them up with the inside edge of the opening so as they over hand on the outer side, one by ½” the other by 1”. Always place the galvanized hardware cloth on over the face which will be facing outwards towards you when fitted into place.

Always start off the flow through system with six pieces of newspaper, add 4” to 6” pre soaked sphagnum peat moss (damp, not soaking wet) on top and begin adding food scraps.

To help maintain the pH level is to layer your green (i.e. vegetable scraps) and brown (i.e. shredded newspaper, cardboard) as well as add ground eggshells when available in moderation.

After two or three months, use a garden claw to lightly rake the underside of the weed whacker line from side to side to remove the finished vermicompost. This can then be performed weekly if the system is setup and functioning correctly.

Bruce

]]> http://wormcompostingblog.com/worm-compost-bins/how-to-build-a-flow-through-worm-bin/feed/ 61 http://wormcompostingblog.com/getting-started/worm-bin/ http://wormcompostingblog.com/getting-started/worm-bin/#comments Tue, 21 Apr 2009 22:13:17 +0000 Bruce http://wormcompostingblog.com/?p=5 There are a few essential items needed when starting in your worm composting bin. You can begin your worm composting hobby or business for just pennies on the dollar and begin to reap the rewards from your worm composting within a few months.

First of all you will need a bin or “worm factory”. Allow me to take a minute here and explain the difference.

There are a number of types of worm factories available for around $60.00 to $90.00 which come by themselves or with bedding… Most will emphasize the fact they come with a spigot for which you can drain the liquids which some refer to as worm tea (in essence it is not really worm tea but will explain in a separate post). The important fact here is that if you have liquids draining from your vermiculture setup, you have too much moisture and your worms will end up dying.

In short you can purchase a rubber maid type bin, being sure it is opaque as to block out light for under $5.00. All you need is a drill so as to make 1/4″ holes on the bottom and 1/16″ holes on the top of the bin and the lid. This is important for air flow as worms require a mix of moisture and oxygen. In fact, I personally do not even place the lids on mine; however your spouse may get upset if you have an uncovered worm bin in your kitchen or guest bedroom

I found in the past that by placing the lid on the worm composting bin, there was not enough air flow, even when I drilled more holes in the top side.

Utilizing a lid seems to trap more moisture within the bin, hence generating mites throughout the worm bedding. Now most mites will not be harmful towards your worm population, however as I learned in Latin many years ago, there are exceptions to every rule

You will need to do a little more work if you decide not to use the lid on your bin. I find that the moisture more readily evaporates; hence I need to spray my bins more often with water. I personally use a small B&G sprayer to mist my worm bins since the number of bins is growing rapidly, however a simple spray bottle is sufficient for most. Do NOT simply use a watering can or other means to add water. You need a fine mist as to avoid over watering and to evenly disperse within your worm bin.

For some simple directions on building a worm composting bin click here (link opens in new window).

Next you will need some bedding for your worms to exist in. Many folks recommend coconut coir, peat moss… in reality all you need is shredded newspaper and brown cardboard. Shred enough paper to place between 5 to 6 inches deep in your worm bin. In fact, red worms will not be able to live in just peat moss or coir by themselves; however they can survive on just newspapers. I do not recommend just newspapers as you will have much healthier and larger worms with the proper food, something I will get to in a minute. Another item to add is brown cardboard. Do NOT use the shiny waxed cardboard and best if plain brown.

Now the rule of thumb is to soak your newspaper and wring out so as when you squeeze it only a drop or two squeezes out between your fingers. I have tried this and found this makes your red worm composting bin to wet, especially once you begin adding more food for your worms.

I simply use a B&G sprayer, since I have a large number of bins, however you can simply use a spray bottle to moisten your bedding. I do have a plant soil moisture meter and slide it in horizontally while moving it back and forth. I have found around 7 to 8 on a scale of one to ten works best (70% to 80%).

Next you will need food for your worms. OK worms love most food scraps. There is a lot of ground to cover, not just on food but as a whole in general, but I am just going into the basics here.

Worms love most vegetables, however keep away from those high in citric acid such as lemons, tomatoes, oranges etc. Also avoid or use very little onion and garlic scraps. Lettuce, greens and most vegetable scraps are great to add. Limit starchy foods such as potatoes, bread etc. Banana peels are good, however limit as they tend to add more of an odor and also seem to attract mites in your bin, which for the most part are OK but not necessarily something most folks want a bunch of

Do NOT place meat, dairy products or oily foods in your bin as this will end up killing your red worms.

Since worms have gizzards much like a chicken, hence they require grit in order to digest food. You can add a handful of dirt, sand or I prefer ground up eggs shells. Be sure if using dirt or sand that is purchased that it contains no harmful ingredients such as salt or is not bleached in the case of sand.

When adding food to your bin, place in a different corner each time under some of the damp newspaper as this will help reduce both odor and the infestation of fruit flies.

I highly recommend placing your bedding and food into your bin at least one week prior to the addition of your red worms. I usually do this with fresh bedding two to three weeks prior to adding worms. This allows for the food scraps to begin to break down and build up organic matter, something that is required for red worms to be able to eat it.