I've been a backyard beekeeper for eight years, and over that time I've experimented with different types of hive designs including Horizontal Top Bar, Warré, and the foundationless Langstroth. I've made plenty of mistakes over the years, mostly of the 'killing with kindness' variety, but gradually I've learned to let the bees do what they've been doing pretty well for 130,000,000 years. As much as possible, I try to lightly manage them in order to split strong colonies in spring to increase the number of hives I keep and harvest surplus honey. In my experience the Warré style of top bar hive has had the most success with over-wintering colonies, but I continue to experiment and learn.

While I generally don't feed established colonies, there are three conditions when I do feed:

When installing a new package of bees into a hive in spring
If a colony appears light on stores entering the fall
If a colony seems like it might starve in late winter, before spring bloom begins

I've tried a lot of different methods for feeding over the years, but the best I've found yet is the hive-top feeder detailed in this Instructable.

In my experience, what I like about this design compared to other internal hive feeding methods:

No dead bees due to drowning
Minimal disruption of the hive atmosphere when refilling
No need to for veils or protective gear when refilling
The design can be adapted to both Warré and Langstroth style hives

Construction is fairly simple with basic woodworking tools and skills. The dimensions in this Instructable are for my Warré hive, but with some modification it can easily be adapted a Langstroth hive - I use both sizes myself.

Step 1: Lumber, Supplies & Tools - Requirements and Options

There's a lot of room for flexibility in this design, but following are the materials I used for my Warré feeder:

Lumber:

(2) 1" x 4" x 13 1/2" (long sides of the feeder)
(2) 1 x 4" x 11 5/8" (ends of the feeder)
(1) 1" x 3" x 12 1/2" (interior wall)
(1) 10" x 11 7/8" x 3/8" (plywood floor)

Supplies:

Galvanized mesh material (2 pieces trimmed to size) - I use gutter screen
1 1/4" Deck screws
Approx. 3 oz. (75 g) Bees wax

Optional supplies:

corrugated joint fasteners
moisture-resistant wood glue (such as TiteBond II Premium, or similar)

Tools:

Table or Radial Arm saw
Dado blade (optional - you could create the dadoes using a standard blade and multiple saw kerfs)
Hammer
Metal snips
Cordless drill or screw driver
Sauce Pan (or similar size pot) and Pyrex measuring cup (for melting wax)
Nylon (or similar inexpensive) Paint brush
Staple gun

Sugar Syrup (the reason to build this in the first place)

Spring Syrup - 1:1 (1 part white cane sugar to 1 part water, by weight)
Fall Syrup - 2:1 (sugar to water)

My Warré hive dimensions vary somewhat due to differing lumber dimensions as I've built them (1" vs. 4/4 rough). I now use only 4/4 for my boxes as it tends to be less expensive than finished (planed) pine and offers more insulation value. The most important thing is to measure your hive boxes to get the overall feeder dimensions that work for you.

Step 2: Cut Lumber to Size and Add Dado Cut for Floor

For this project I used 1"x4" pine left over from a remodeling project. It had been primed and painted, but that's not necessary, as you'll be sealing the wood that will hold the syrup with beeswax.

Safety Note: I own a vintage (circa late '50's) Sears Craftsman table saw, which doesn't have the safety guards of newer saws. I still have all my fingers after 30 years of use, but I'm very very careful. Use the safety stuff if you have it. No need to be the first 9-fingered (or less!) beekeeper in your neighborhood.

I first cut the 2 long box sides and 2 shorter ends to size, making sure I measured twice before cutting. I then cut a piece of 1" x 4" pine to be used for the interior wall.

I then fit the table saw with a dado blade set to 7/16" width in order to cut the slot into which the plywood floor will fit. Adjust the height of the blade to cut a dado depth of 5/8". My goal in fitting the plywood floor into this slot is to have a little extra room between the edges of the plywood and the frame walls to allow for expansion due to humidity, so you'll need to size accordingly.

Next I set my table saw fence so that the edge of the dado nearest the bottom of the box would be approx. +/- 5/16" (+/- 8 mm). This approximates 'bee space', or the amount of room a single bee needs be able to move between surfaces. More space could result in bees attaching comb to the underside of the feeder over time. Less space could prevent them from being able to move between the top bars and the floor of the feeder.

After testing my measurements on a piece of scrap, I ran both long sides, one short end, and the interior wall through the table saw. The other short end doesn't need a dado cut.

Step 3: Cut Dadoes in Long Sides

Next I adjust the dado blade to a width of 13/16" to accomodate the thickness of the pine used for the interior wall. Depth of the blade is set to leave a dado approx. 3/8" deep (enough to allow room for expansion of the wall due to humidity when on the hive). I always test both the width and depth of my settings on scrap wood before making any final cuts.

The table saw fence is set so that the dado would be approx. 2 1/4" from the end of the board. Once the box is put together, the distance between the interior wall (which fits in the dado we're now going to cut) and the outer wall will allow the bees to travel up and into the feeder.

NOTE: It's important to remember before cutting this dado in both long sides that one of the side boards will have the narrower dado (perpendicular to the one we're cutting) along one edge, and the other will have it at the opposite edge (see illustration above). In the past I've made the mistake of cutting both sides identically - not good! ;-).

Step 4: Assemble Box

Time to assemble the feeder box.
To assemble the box I've used deck screws, or a combination of screws and corrugated fasteners. Sometimes I've glued the joints as well. I haven't experienced any failures of the assembly with any of the methods, so there's room for improvisation here. If using screws, be sure to drill pilot holes before driving the screws otherwise the wood may split as you drive the screw home. I use pipe clamps to hold the box square as I drill / screw it together.

After assembling one long side to the two exterior short ends, I slide the interior wall (which has been ripped to it's final 3" depth) into the wide dado in the side. I then slide the floor into the narrow dado, and finally fit the 2nd long side into place (see the gif animation in the introduction for the order of assembly I use). Tack the floor in place from the underside with 2 small finish nails, one in the middle of each long side, driven up through the side wall and into the plywood floor.

After assembly you'll notice two openings at the end of the feeder, left by the narrow dado cuts for the floor. If left open, these can act as entrance / exits for the bees, which in certain circumstances can be a good thing. I use small pieces of sheet metal tacked with finish nails on one end to allow them to swing open or closed. In normal use they'd be closed, to keep the bees in the hive and make refilling easy without donning protective equipment. But in cold weather, or if the feeder is kept on for a lengthy amount of time, you may want to give the bees a top entrance / exit. Left open, these holes work well for that.

Step 5: Waterproof With Beeswax

After assembling the box, it's ready for waterproofing.

I use melted beeswax for this; I have plenty on hand that I've melted from old combs, it works great, and it has the smell of a hive that bees like. Commercial sealants would probably work, but I try not to use any synthetics if I don't have to. If you don't have your own supply of beeswax you can try a local beekeeper, or purchase it from many bee equipment suppliers. You can also buy it at some craft stores, but it's much more expensive there than beekeeping supply businesses.

First step is to melt the wax. Beeswax melts between 143 and 151 deg. F (62-66 C). The flashpoint (temperature at which beeswax flares up) is 490-525 deg F (254-274 C). It's important for safety to make sure you melt the wax gradually and on low heat to avoid nasty things like singed eyebrows, or worse. I use a double boiler-like arrangement made from an old pyrex measuring cup which holds the melting wax, which in turn sits inside a pot of water, brought gradually to a simmer. It can be a chore to clean up splash waxed where you don't want it, so cover important surfaces with newspaper or similar.

Once the wax is completely melted (roughly 20 minutes for the approx. 3 oz I use), I turn the feeder on edge and gradually pour wax onto the joints (at the floor and wall corners) of the box, sealing them. It takes a little practice to both pour the wax where intended and rotate / tilt the box so it runs along the seam before it hardens. Having a little help with the pouring or tilting might make the process easier. But not to worry - as long as the edges are sealed, that's all that matters. Bees do not give points for neatness.

The joints sealed, next an old nylon paintbrush is used to paint wax onto the floor and interior walls, sealing them. Given that the pine I used for walls in this project had been previously painted with an exterior latex, I probably didn't need to paint them with wax, but I had it on hand and decided to go ahead and coat them anyway.

Finally the sealed box is filled with water and tested for leaks. Any gaps in the sealing wax can be re-melted using a hairdryer, allowing the wax to melt into the gaps and re-seal.

Step 6: Add Mesh Ladder and Barrier

The feeder uses 2 sections of galvanized wire mesh as both a ladder for the bees to climb on internally and as an external barrier to prevent them from accessing the majority of the syrup box, possibly drowning and/or flying out when refilling the feeder.

The first section of mesh is long enough to span the top edge of the interior wall and wide enough to form a ladder starting at the top of the wall, then vertically down and onto the floor. When cut and fit, the mesh ladder is stapled along the top edge of the wall.

Next, another section of mesh is cut to the outer width of the box, making sure to cover the tops of the wide dadoes - you don't want bees escaping there. After making the initial cut to size, the back edge of the mesh is stapled to the back top edge of the box, and then the mesh is stapled along both sides to just in front of the dadoes.

With a pair of metal snips the mesh is now cut along the sides so that, when bent downward, it will span the interior walls of the box, making it impossible for bees to pass from inside the mesh 'fence' to outside and into the main feeder area. This section of mesh should be long enough so that the bottom edge (approx. 1" wide) can be bent to follow the floor. Refer to the gif animation in the introduction to see this illustrated.

Once the mesh is trimmed and stabled, the bottom edge can be pressed into the wax on the floor to keep it flat.

Step 7: Place Feeder on Hive and Fill With Syrup.

The feeder is now ready to be placed on the hive.

Remove any interior top board or quilt and make sure there are openings between top bars so the bees can access the feeder.

Add sugar syrup to the feeder, either 1:1 (sugar to water, by weight) light syrup in spring or 2:1 heavy syrup in fall. Initially I only add enough to fill the feeder to about 1/2" deep to make sure no leaks lead to a waterfall of syrup in the hive. I splash a few drops down through the mesh and onto the top bars of the box below to alert the bees that there's good stuff up above. In my experience it takes only a few minutes for bees to quickly start moving up to the feeder.

Again, the great things about this feeder design is it's easy to fill without bees flying out of the hive, there's very little (or no) drowning of bees, it's quick to fill, and little of the hive is exposed when opening it to refill.

How much you feed depends on the bees needs at the time. In spring when establishing a new colony from a package, feed until there is some stored and capped honey at the top of the combs and blooms are out.

In fall it depends on what how much the bees have stored over the summer. I tend to harvest surplus honey from established hives in the spring, after I know they've made it through winter with honey to spare. I'd rather not take honey in the late summer unless I know for sure the bees have more than enough to winter on. I don't want to take too much at the end of summer only to end up feeding sugar syrup (a poor substitute for their own honey) in the fall to get them through the winter.

Best to consult a local beekeeper or club to find out what they recommend for the weight of honey stores heading into winter for your locale.

I hope you've enjoyed this Instructable. I wish you great luck with your bees and enjoyment of them for years to come!