In the cross half-lap joint, you should chisel the
A cross half-lap joint (fig. 3-24) between
waste out rather than saw it out. To make the
members of equal cross-section dimensions is laid
chiseling easier, remove as much stock as possible
out and cut as follows: If the members are of the
with the saw first. Saw a series of kerfs between the
same length and they are to lap each other at the
shoulder cuts. In chiseling, make a roughing cut
midpoint, place them face-to-face with ends flush.
down to just above the cheek line with a firmer
Then square a center line all the way around. To
chisel and mallet. Hold the chisel bevel down.
test the accuracy of the center calculation, turn one
Finish off the bottom with a paring chisel while
of the members end for end. If the center lines still
holding the chisel bevel up.
meet, the center location is correct.
You can use a circular saw to cut half-lap
When making a cross half-lap joint, you should
recesses and cross half-lap recesses. For an end
put the best wide surfaces up and mark each face
half-lap recess, set the table saw blade above the
plainly. Lay off one-half the width of a member on
table a distance equal to one-half the thickness of a
either side of the center lines; then, square the
member. Place the member against the miter
shoulder lines all the way around. Again check for
gauge, set it at 90° to the saw blade, and make the
accuracy by turning a member end for end. If the
shoulder cut. Take out the remaining waste by
shoulder lines meet, the layout is accurate. Next,
making as many recuts as necessary.
gauge one-half the thickness of a member. Do this
from the face of each member and score check lines
For a cross half-lap recess, you should proceed
on the edges between the shoulder lines. Next,
as follows: Set the table saw blade or dado head so
make the shoulder cuts, sawing from the back of the
its height above the table is equal to one-half the
lapping member and from the face of the lapped
thickness of a member. Then, place the member
member.
against the miter gauge set at 90° to the saw blade
Figure 3-24.--Gross half-lap joint.
3-20