There are three variations of a rabbit joint.
- The basic rabbit joint where one piece of lumber is notched to accept a second piece of lumber, as shown in Figure 1.
- The half rabbit joint where the both pieces of lumber are machined to fit into one another, as shown in Figure 2. Half rabbit joints are commonly used at the ends of lumber when making boxes or when fitting the top and bottom shelves to bookcases and cabinets.
- The stopped rabbit joint or as it is sometimes termed the blind rabbit joint, where the dado is not extended the full length of the board, as shown in Figure 3.
Figure 1 - Basic rabbit joint
Figure 2 - Half rabbit joint
Figure 3 - Blind rabbit joint prior to assembly
From the end view, it does not appear that a rabbit has been made in the lumber, as shown in Figure 4.
Figure 4 - Blind rabbit joint after assembly
When a rabbit joint is used with vertical and horizontal pieces, such as a bookcase, you get a mechanical transfer of the weight from the horizontal to the vertical pieces, as shown in Figure 5.
Figure 5 - Rabbit joint load
The depth of the rabbit joint is usually half of the thickness of the lumber that the dado is made in although there is no hard and fast rule regarding depth. However, unless there is a very compelling reason the dado should never be more than half the thickness of the lumber and not less than a third of the thickness of the lumber.
Rabbit joints can be strengthened and reinforced by the addition of nails or screws through the mating pieces of lumber.