05/05/2020

Light Saber Build Part3

By snorlaxprime

Finally I get around to finish off the light saber case. And this write up is ready in time for May 4th.

This is the continuation from the previous write up, Light Saber Part 1 and Light Saber part 2.

Step 1. Gather all the materials

  • PVC Pipe
  • Foam for diffuser
  • Toy sword handle as the Blade arc tip
  • Recycled case for speaker and charging
  • 4 PDT Switch
  • Push Button for Trigger
  • On/Off Switch
  • 3x 3.7V 3400mah Rechargeable Batteries

Step 2. Preparing the case

I drilled a couple of holes through to fit he Push Button Trigger and the 4 PDT switch. The PDT switch is used to swap between charging and during the play mode.

Here is the updated Schematics and Circuit:

I also test fit the charging circuit which will be located at the bottom of the Lightsaber to make sure it fits, the speaker is located at the bottom too.

Just before that the 3 rechargeable battery is a bit tight, so heating up the PVC slowly to make sure that it fit is quite important.

What I also figured out is charging the battery can kill the charging circuit, so I added a diode to prevent the reverse current from the battery back to the charging circuit. I killed two of my charging board because of the reverse current.

Step 3. Putting it all together

What I found the most frustrating part is to squeeze everything into the space. I should have design some of the cables to be just right. I started with the battery at the bottom to make sure it stays well.

Then comes the fun part fitting and squeezing the MP3 player in then the button comes next, make sure they are fit in. I had such a thick cable for the charging switch, so I need to make sure they are snugly fit into the case.

Then the final 2 button is quite a struggle as the 4 PDT button needs to be pressed before they can fit into the tube, and the push button needs to go in slightly slanting to make sure it gets it. Don’t forget to seal all the open wire to make sure they don’t short circuit. I burned one Arduino nano because of short circuit :(.

Step 4. Smoke Test

Once everything is on then you can take a deep breath and turn the power switch on. No smoke? good. Press the ON button and hold for one second, the light saber should come to life.

You can switch colour by pressing the on button 3 times. When you move the light saber around the sound effect will play randomly when there is a sudden movement of the hilt simulating the battle sound.

The following video shows you some of the special effects.

Thanks for reading until the end of this post. Please follow if you like this post. The full source code can be downloaded here.