Starting a top bar bee hive

December 2018 update: The post below describes my first attempt at starting a top bar hive. My cunning plan didn't work out as I hoped, so I ended up trying a different approach - which did work. I describe my successful use of a "brushed swarm" in my later post here. However the process described below was useful for getting me some comb on top bars, which made the brushed swarm much easier. My evolving hive design is described in my post here. 

Today I started my first top bar bee hive. This has been coming for some time, and taken a lot of thinking, planning and building. Now to see if it works!

The brown top bar hive is on top of (and part of) the white 10-frame hive. The queen excluder is below the top white (brood) box.

Why top bar?

There’s been a long lead up to this: Erika and I kept bees for years (I started by catching a swarm in Abney Park Cemetery, Stoke Newington, London with my mate Gomez in 1985), until family life overwhelmed and we gave our hives away. A couple of years ago I got sucked back into beekeeping when Erika’s mother and brother started hives in Stanthorpe. They bought 10 frame, full depth boxes, so I ended being the only person who knew how to do bees, wasn’t scared of stings, and was tall enough and strong enough to lift the boxes.
10 frame full depth boxes (supers) are very heavy things, when full of honey. They need to be lifted high: onto a hive of up to 4 boxes (sometimes more), which is already on a stand to keep the hives above the grass and away from toads, termites, ants, etc.. Most times you go to do anything with the bees, it starts with climbing up and lifting a 40kg+ box full of sting-ready bees down off the top. I’m finding this is at the limit of my strength, which I don’t think is a good idea. I’m also squashing a lot of bees, especially when replacing heavy boxes onto crowded hives. This feels bad and gets the bees cranky.
There is no way my late-70s mother in law with arthritic fingers is going to be doing anything much at all with these he-man hives, which is a real pity. My strong but short brother-in-law is also not able to do much work on his hives when the honey is flowing. Both of them miss the pleasure of learning about the bees, the hives get neglected between my visits, and I end up responsible.
So I’m feeling pretty strongly motivated to find a way of keeping bees that doesn’t involve frequent heavy lifting from ladders.
Top bar hives fix this. They use a single box - one level. They don’t use supers (unless you get clever), so nothing heavier than a single comb (equivalent to a single frame) needs to be lifted (unless perhaps the hive has a heavy lid). They are managed by frequent, low-intensity visits, instead of periodic major exercises. I’m hoping they are suited to a determined old lady who has a fascination with nature.

Home made

I also like the whole top-bar style. Especially that I can make every part of the hive myself, from wood we have grown and milled, with my existing tools. The top bars can be sawn from off-cuts which would otherwise be firewood.
The hive I started today has been made in my workshop at Mt Glorious, and brought out to Stanthorpe this week. I’ve made 2 nucleus hives (small hives to start a new colony in). One has an open bottom and is designed to fit on top of a standard 10-frame box - that’s how I’m planning to start the hive with a colony of bees.

This brown top bar hive has no bottom, so it's open to the 10-frame brood box below it. The lid has a layer of pine boards on top of the top bars for insulation, then a corrugated iron roof.

The other box has a bottom and is planned to be self-contained, housing the new colony when it is separated from the 10-frame hive.

This is the top bar nucleus hive with a bottom, intended to house the independent colony when it's separated from the mother hive. 

The boxes are made from un-treated slash pine boards I cut years ago with a chainsaw mill, but which have been slightly attacked by borers (because I didn’t treat the wood with borax after milling), so the wood can’t be used for furniture. If it works for a few years as bee hives, I’ll be pleased - and in the dry Stanthorpe climate I expect them to last fine. The boxes have one coat of water-based paint (from the tip).

What design?

I’d like to benefit from other people's expert experience, but it took some time to decide on a design - I even started and then abandoned some bars and a box after deciding they weren’t the way to go (bars too short and box too deep).
My main concern with hive design is to avoid combs breaking off on hot days, due to being too deep and narrow. I’ve used the top bar design of Les Crowder, whose excellent youtube video is very helpful, and whose book I bought. Les uses bars 20” long, which I metricised to 505mm. I was a bit torn between Les’s size and the “Standard top bar” size of 19 1/2” (495mm), but if I ever want to I can easily cut mine down to standard length. I’ve made the box sides from 250mm wide boards, tilted at 60* to horizontal. This all results in internal dimensions of 464mm max width (at top) and 200mm depth.
To make the top bars, I’ve dressed my timber to 35 x 25mm section, 505mm long. I have then rebated both sides and ends of the bars, to leave a bar 18mm thick, plus a square ridge along the bottom for the bees to start their comb on. I ran melted beeswax down the ridge, which is advised to help the bees start their combs where you want them to.

Top bar, with waxed ridge planed into the bottom face (upside down in picture)

Getting bees into the top bar hive

Today’s great event is simply the placement of the open-bottomed top bar box onto one of the family's 10-frame hives. This took some thinking, right up to this morning, and I hope it works.
Bee keeping context is that it is mid-summer, with a good flow of honey from local Orange gums (first Orange gum flowering in about 10 years). I’ve chosen a strong 10-frame "mother hive” which is working hard on honey production.
My first step was to take off a full box of honey from the top of the "mother hive". I can extract this tomorrow with some other boxes.
Then I inverted the order of boxes on the mother hive: I took off the 2 (half filled) honey supers from the brood box, and removed the queen excluder from the brood box. I took the brood box off the base board and put it aside. The 2 honey supers were then placed onto the base board, and the queen excluder placed on top of the honey supers. The brood box was then placed on top of the queen excluder, making a 3-box hive with brood box on top. The open-bottomed top bar box was then put on top of the open-topped brood box, with top bars and a lid on top of the top bar box. There are no openings in the top bar box.

Hopefully the bees are building combs exactly along the bottoms of the top bars

Now the bees have access to the top bar box, to hang combs from the top bars. The queen has access to lay eggs in the new comb. My plan is that brood and honey combs will be built into the top bar box, and when it’s all looking sweet, I can transfer the combs (on the top bars) into the other top bar box, where the bees will find themselves queenless and rear a strong (but fair) queen and we will have an independent top bar hive to work from.
Once a colony is established with a queen in the nucleus top bar hive, I can build a longer hive (I'm planning on 1200mm) and shift the colony into that, for proper production next year (if I'm lucky).
The main risk (I can see) is that the bees ignore my instructions and build their comb all over the place. I’m hoping weekly visits will be able to push things into line. In hope of encouraging compliance, I have made 3 top bars with central grooves instead of ridges, and attached some strips of foundation wax into the grooves with hot wax. At the last minute I realised that I’ve put in the foundation in the wrong orientation: normal comb has vertical lines in the hexagons, I’ve put the foundation in with horizontal lines. I don’t know if bees will work with wrongly-oriented foundation, let’s call this an experiment…
The other risk is that the queen rearing is unsuccessful, and the top bar hive dwindles on separation. If that happens, I can re-unite it with the 10-frame hive and try again when the season is good.

Update 24 August 2018

Progress has been slow with the top bar hive. About the time I installed the top bar super, the Orange gum honey flow stopped. As there are only very few honey-producing tree species locally, and it's been very dry, honey production has been stopped since. 

The consequence of this for the top bar project has been that without a honey flow, there has been no comb building, and the top bar box has been pretty much empty. A few months ago a little burr comb was built on the tops of the brood box frames, so I tied some of that onto a top bar to help get things started. The bees did anchor the comb to the top bar, but really nothing happened more than that. 

Today, however, I had a look and found grand progress! A few bushes and trees, mostly not native locals, are flowering, and giving the bees a light honey flow, so they're building some comb. Here are some pictures: 

This bar had some wild comb tied on, and is the end frame of the top bar super. Honey and comb!

The second top bar, with beautiful brand new comb

Just getting started on this bar

To my surprise, the comb is being built exactly where I asked them to. Consequently it was easy to lift out the bars to inspect the comb. To try to build on this alignment, I shuffled the 2 first bars apart and added in a bare top bar between them, hoping this will guide the construction of a new comb on the bare bar.