Unsurprisingly our site gets visitors looking for instructions on building Tanzanian top-bar hives. We have felt some guilt over not providing any such, especially having failed to document our construction of Beatrix. We shall do better with the two hives currently under construction but until then we can at least write about making top-bars for Beatrix since we did take some pictures of that part of the project.

We used a tablesaw with a tilting blade. While some steps could be performed with other tools we restricted ourselves to a tablesaw since this is a tool to which most beeks could get access. Before we proceed, let us repeat our disclaimer. This is not a how-to-do-it presented authoritatively by experts but rather a how-we-did-it presented by mere mortals and most certainly not a how-you-should-do-it whatever your skill level. If you should wish to do likewise, use your own best judgment and observe safe practices. As usual clicking on a picture displays a larger version. Now on to the sawdust.

Our general sequence of batch operations to efficiently produce top-bars is:

  1. Crosscut the long boards into billets.
  2. Rabbet the ends of the billets. (Optional if the bottoms are left flat in step #4)
  3. Rip the billets to make the bars.
  4. Profile the bars.

And now the specifics.

Step One We began with eight foot long two-by-fours readily available in the USA at any lumber yard or DIY store. Wider boards could certainly be used to produce more top-bars per piece of lumber but these were relatively cheap and straight boards easier to find. Beatrix’s dimensions required us to cut them into 19 inch lengths. There are no pictures of this as it is too simple an operation to bother documenting.

Step Two The sides of Beatrix have a 5/8 by 3/8 inch rabbet into which the top bar ends should fit, so we accordingly rabbeted them as well. A router table or dado blade for the table saw might have been used but given the thickness of our billets multiple passes would have been required. So we opted to simply use the table saw to cut out the chunk needed from each end. The picture shows the progression of one billet end.

We set the height of the blade to not cut all the way through the billet but leave the 5/8 inch needed for the rabbet in the hive side, so 7/8 inch in height since a two-by is actually only an inch and a half thick.

Then we crosscut the billet at 3/8 inch from the end and repeated for the other end. The resulting slot is seen in the second billet of the picture although the billet is displayed with its bottom side up while it was cut with its bottom side towards the table. Process the rest of the billets.

For inexperienced woodworkers we point out that on such crosscuts (using your miter gauge or sliding table) you should not have the end of the billet riding against the tablesaw fence. Neither do you wish to have to measure for each billet. One solution is to clamp a short bit of wood to the start of the fence then set the fence so that when the end of the billet butts up against the wood it is at the correct position but will have a free end before it hits the blade.

We next had to make a perpendicular cut from the end to meet the first cut. This required running the billet over the blade with the billet sticking up in the air and that required removing the blade guard. Hard to do accurately and safely when the workpiece is narrow and taller than the fence. Those of you with tenon jigs would do well to use them now. Those without (as are we) should attach a sufficiently tall auxiliary fence.

Ours is cut from a sheet of MDF and held on the usual fence with universal fence clamps. The end of one of these fits into a 3/8 inch hole in whatever one wishes to keep snugged against the fence. We drilled two such holes into the bottom edge of our MDF, deeper than the usual fence is high. Next we drilled holes at an angle from the clamp side of the MDF to meet the vertical holes. After some filing and scraping we could fit each clamp into a slanted opening and push it down into the vertical part. We hope the pictures make this clearer.

We set the blade height to 3/8 inch and the fence to 5/8 inch from the blade. Standing a billet on end with the top side of the billet against the tall fence resulting in the slot previously cut facing away, we slid it along over the blade and the cutoff was free of the blade and not caught between blade and fence. As before, turn the billet over and repeat. Process all the billets.

Do not try to clear away the cutoffs by hand while the blade is spinning. Fingers should be kept well away. Even clearing them with a stick has hazards as the cutoff may be pushed against the spinning blade and flung.

Step Three We intended our top bars to all be one and three-eighths (1 3/8) inches wide. We set the rip fence two inches from the blade so that running a billet through lengthwise gave us one top-bar with a somewhat narrower billet between the blade and fence. If that math seems strange then consider that our by-four lumber is actually only three and a half inches wide and the thickness of our blade pulverizes about one eighth inch width of material.

The billet was pushed through with the bottom up. That is, the tabs we made by rabbetting were in contact with the table. Otherwise blade would cut down through a thin, unsupported tab and possibly snap it off.

After processing all the billets we used one of the new top-bars as a spacer to reset the fence and ran the reduced two-inch wide billets through a second time to get a sliver of waste cut off and a second top-bar.

We might have used a single set-up with fence an inch and three eighths from the blade for both top-bars from the billet but as a matter of safety one should avoid having the smaller piece between blade and fence. In our case we were perhaps being somewhat foolishly cautious.

Step Four And now the part requiring a tilting blade. We had previously announced our intention to use an elaborate profile but that would have required two set-ups and four passes per top-bar. We instead opted to simply slope the sides to form a ridge running down the center-line of the bar. The fence distance and angle of the blade were set by eyeball and experiment. We did not achieve a sharp apex but the one eighth inch flat spot does not negate the strong hint for comb direction being provided.

The picture shows the cross-sections for the starting top-bar, the results of one pass, and the final result after flipping the bar and making the second pass.

We must point out that with the blade raised high enough for efficient cutting (a tooth at the highest part should clear the workpiece) there was not much room between the top of the blade and the fence. Our push stick took a few shallow cuts but it is still useful. The same would not have been said for our fingers.

If your tablesaw blade does not tilt then you will be reduced to simply cutting a shallow lengthwise groove down the length of the blade to be filled with beeswax or have inserted something like a popsicle stick or narrow strip of foundation. The top-bar would have its bottom towards the table for this cut.

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