Set the adjustable fence with a single piece of stock
spanning the fixture. Clamp the wood firmly, yet still
lightly enough to allow it to easily slide.
Reposition the stock in the assembly fixture with one
bevel near the center.
Apply a bead of thick CA to the second bevel face. Insert the glued stock into the fixture and then push the
Next I install a simple jig made from a few scraps of
plywood glued together with medium CA. It features a spline
to reference the sander’s miter slot and an angled fence to
position the stock.
I use another must-have tool to make this jig: my Byrnes
Model Machines table saw. It makes quick work of accurately
sizing a strip of 1/16 plywood to fit the sander’s miter slot. The
saw has a micrometer fence adjustment that lets me sneak up
on a perfect fit—a few thousandths of an inch at a time.
I shim the spline off the bottom of the miter slot with
scrap balsa. After applying a light bead of CA to the spline, I
position the jig base against the disk and press it into place.
The fence is another strip of plywood that I secure at an 8: 1
bevel angle. My jig base is 6 inches wide, so I measure up 3/4
inch on the left side and align the fence with that mark and
the opposite corner.
A single spring clamp is more than enough to hold the jig
in place with the lower spline in the miter slot. Now it is a
simple matter of turning on the sander, aligning a piece of
stock with the guide, and pushing it into the abrasive until I
have cut fully across its thickness. I do the same with a second
piece and it’s time to join them.
The Glue Up
Many a scarf joint has been completed with a bead of
glue and a finger pinch, but that is far from ideal. Glue can
55 Model Aviation JUNE 2014 www.ModelAviation.com