Build a Bike Boom Box

Step 8 Mount the conduit pieces on the tube

This is a tricky step because several pieces are flopping around at once. The goal is to attach the two pieces of conduit to the big tube so that the rack will sit on them in the right place.

First, temporarily install a speaker in the end closest to the amplifier holes using two screws. This is the front speaker. The rack's upturned front end will have to clear the speaker, so it has to be there to get the fit right.

Place the tube on the workbench upside-down, that is, with the bottom of the speaker pointing up. The amplifier holes will be about 30 degrees above center. The speaker has a center line molded into the grill to make it easy to align with the center of the rack.

Place the two conduit pieces on top of the tube and hold them in place with the upside-down rack. See the picture to understand what this means. Position the two conduit pieces about 1/4" away from the end of the tube with the speaker grill. This end has the upturned end of the rack also. Check the centering of the rack with the speaker grill to be sure the rack is properly positioned on the tube. While holding everything just so, get out your Sharpie (you had it handy, right?) and mark the tube at each end of the conduit. The important end is the one near the speaker, unlike the photograph.

Now take off the rack and conduit, and hold up one conduit piece at the mark. Using a handheld drill with a 7/64" bit, drill a hole through the conduit hole closest to the speaker. Install a #8x1/2" screw in the hole you just drilled.

Align the conduit carefully with the direction of the tube. Drill a hole in each of the other two conduit holes and install screws in them.

Repeat the procedure for the other piece of conduit.

Hold the rack on the tube-conduit assembly and see how it fits.