I started construction by cutting the PVC tube into a total
of four 20" sections. For the tweeter/crossover modules, I
chose to use 10" sections, of which two were needed. 1" wide
by 7" long strips of the 3/4" MDF support the weight of the
assembled tubes, as I wasn't keen on the idea of the tubes
being connected at only one point. The strips provide ample
support to the enclosures and prevent side-to-side rocking.
Next, the enclosure end caps—the easiest (and safest)
method is to start with the outer diameter. Since I am using
material cut out of the MDF, I have to add the diameter of
the spiral-upcut bit (1/4") of the router to both sides of the
diameter (6-1/2" for the PVC diameter). I also add 1/16"
for wiggle room and set the circle jig to 7-1/16". Now, this
is important: DO NOT complete the cut! I left about a 1/2"
section on both sides so that I could cut out the center of
each cap for the relevant woofer mounting hole, port, binding
post terminal cup, or for the tweeter recess and cutout. Go
back and cut the remaining section to remove the end cap
from the sheet, and file it to round. The next step in the
construction process is the determination of where screw and
wire holes will reside on the PVC and MDF strips, marking the
locations, and drilling them with the appropriately sized bit.
Test fit the pieces, using the screws to align the adjacent MDF
strips and PVC tubes. Glue and clamp the end caps to their
appropriate modules (except for the rear cap of the tweeter
tube module.more on that later), and let the bond cure for
at least 5 hours. Next, apply glue to both sides of the MDF
strips, run the screws (with washer attached) and speaker
wire from the woofer module, through the MDF strip, and into
the tweeter module (the screw head inside of one tube and
screw nut on the inside of the connected tube), then secure
everything with the screw nut. Without tightening the screws
and nuts completely just yet, do the same for the other side of
the tweeter tube section. To get everything to align vertically,
place 2" x 4" boards along the outer edges of the tubes (so
that they are touching all of the tubes at the same time) and
clamp the boards together, though not tightly yet. Go back
and tighten the screws that are holding the tubes and MDF
strips together, and then tighten the clamps again. The glue
should cure for at least six hours.
Remember how the rear of the tweeter module was left
open? This is where the crossovers go. Construct eight small
standoffs from scrap MDF, cutting sections just large enough
to install the T-nut, and glue them in their respective places.
One standoff holds the tweeter crossover inside the module,
one holds the woofers' crossover, and two secure the rear of
the tweeter panel, which holds the binding post terminal cup.
This will allow access to the crossovers if it is required. With
assembly complete, time to move on to finishing.
The first step is to remove and smooth out the excess glue.
The glue is easy to remove from the bare PVC, and to sand
where it builds up. After that, lightly sand all of the parts to
roughen them up for paint. Since Fleck Stone® is used as the
exterior treatment, a base coat of the same color is needed.
Apply the Fleck Stone® over the base coat, allow it to dry
completely, and apply a clear coat to protect the Fleck Stone®.
Mounting these speakers to a stand is a matter of personal
preference—I made a stand adapter using a 7" x 7" MDF
plate with two scrap 2" diameter PVC pipes.
