Not sure which joint type is the best for your beekeeping equipment? This article clears up any confusion between box joints or rabbet joints for your hive boxes. With so many options, it's easy to get lost in the confusion.
One of the many questions we are asked is which beekeeping equipment is better, those with box joints, or those with rabbet joints. To help answer this i've consulted many commercial beekeepers and the large majority of them all say the same thing. Before I tell you what they say though, let's look at the pros and cons of both types of joint.
Box Joint Pros:
When condidering box joints or rabbet joints it should be noted that box joints are a strong joint with a large mechanical surface area to transfer forces across the joint.
Box joint cons:
When considering box joints or rabbet joints you should know that box joints are more difficult to make. Box joints Require specialized equipment or jigs to ensure it remains square.
Has several times more joint surface area than a rabbet joint, which allows for far more end grain exposed to the elements, which results in rot much quicker than a rabbet joint unless special care is used to keep the joint sealed (yearly glue and paint).
The joint makes it very difficult to remove and then replace a cupped or rotted single board in the box. Once glued you are not likely to get this joint apart for repairing a single side of the box. Typically you'll end up destroying the other two boards that the board you want to replace attaches to. This means you'll typically buy a whole new box.
Rabbet Joint Pros:
Strong joint when coupled with other mechanical means such as glue and nails. In tests, nearly as strong as box joints. However, it should be noted that both box joints and rabbet joints are far more than enough to handle the weight of hive boxes. You are not going to have a box fall apart using either joint if constructed properly. So the whole debate over which is stronger is really a mute point.
Easier to manufacture, which results in lower cost.
Beekeeping equipment made with rabbet joints has far less exposed end grain. This means a properly manufactured rabbet joint will last longer in the elements than a box joint. The total surface exposed on a rabbet joint is equal to the length of the joint run x 1/2 of the stock thickness, so about 4.5 inches in a deep hive box corner using 3/4 inch stock. The surface area of a box joint corner exposed to the elements in a typical box joint box with 5 "fingers" is (2.75 x 5) + 4.5 = 18.25 inches. So a box joint has nearly 5 times the exposed wood grain as compared to a rabbet joint. This means box joints will rot 5 times faster without proper maintenance. If you make "Blind Rabbets" as pictured above, you actually have ZERO end grain exposed.
Rabbet joints make repairing or replacing a piece of your beekeeping equipment easy, with a much lower possibility of damaging or destroying the other components.
Rabbet joint Cons:
Not quite as mechanically strong as a box joint. It should be said though that it is still more than enough strength for the application it is being used for, namely making hive boxes.
Box joints were used traditionally in making beekeeping equipment and specifically Langstroth hive boxes because 100 years ago we did not have anything other than glue derived from animal hides. This type of glue is eaten by mildew and other organisms when it is wet. This caused failure in the corners of boxes exposed to the elements and therefore a box joint corner made more sense.
These days however with the advent of glues which are waterproof and mildew resistant there is no longer a need for box joint corners, especially in light of the fact that by using them you are actually exposing roughly twice as much end grain of a box to the elements which cause box joints to soak up water like a sponge. You are also doubling the total joint length.
This is the general consensus of the commercial beekeepers I have personally spoken to. Use rabbet joints based on the pros/cons list. What type of joint do we use? We manufacture rabbet joints on all our boxes and equipment. We also use rabbet joints in our own bee yards. We find they last longer with less maintenance than box joints. If you are interested in our select grade, affordable hive bodies, supers, and other beekeeping related equipment, please check out our full line of products.
When considering box joints or rabbet joints for your hive boxes, we recommend rabbet joint hive boxes. This is why we manufacture rabbet joint hive boxes.