In this project, you will install the secondary power switch, the power LEDs (light emitting diodes) and plug the PWM leads into the receiver.
|Caution: Eye and ear protection are mandatory for cuts using the miter saw. It is incredibly loud, and pieces of metal will be flying everywhere. When using the rest of the tools in this project, you will need eye protection. Review all of the general power-tool safety protocols described in Chapter 5 of Kickin' Bot, as well as the sections that correspond to the specific tools used below.|
Part 3: Making the Switch Bracket
The secondary power switch must be mounted to a bracket. The power LEDs can also be mounted to this bracket, which will be made of the same extruded aluminum U-channel you used in Project 6.
click on an image to enlarge it
|Cut a 2-1/2" long piece of the 1" x 2" extruded aluminum U-channel using the miter saw. Clean up the edge, if necessary, with light pressure on the disc sander. Remove any sharp edges on the deburring wheel.|
|Attach the top and bottom patterns to the switch bracket using 3M Spray 77 spray adhesive. Mark the holes on top and bottom with an automatic center punch. Clamp the U-channel in the drill press vise using a piece of scrap stock as in Project 6.|
|Drill 1/4" holes for the two LEDs, and also as a pilot hole for drilling the switch hole. Make sure to use adequate lubrication.|
|Indicate the step on the large Uni-bit that corresponds to a 1/2" diameter hole with a marker, and drill the
hole for the switch. Use a countersink in a cordless drill to clean up the small holes and the deburring tool on
the large switch hole.
Clamp the U-channel in the vise again and drill the bottom two 1/4" mounting holes. Use a countersink to clean up these holes. You can angle the deburring tool to reach the hole edges on the inside of the U-channel, where a countersink won't reach. Remove the pattern and use Goo Gone or another solvent to remove any sticky residue.
|When installed, the switch bracket will touch the bottom of the speed control, and may rub against it. To prevent this, you need to mark and cut 3/16" off the bottom of the bracket using the bandsaw as shown. Use plenty of WD-40, go slowly, and make sure to keep your fingers out of the way of the blade at all times. Use the disc sander and deburring wheel to clean up the edge.|