Inspection Lights

I've made a few inspection lights now. My goal was to save some money and create a light that was portable and worked for me. I also like the 18650 batteries and used them for all these lights.

The first ones were 12v, corded (to batteries), and used strip LEDs. They used battery packs I built for my dive light (12v - 3S/2P). I used a 1/4 square stick and put LED strips down all sides - overlapped at the end. The White light is very useful. I craeted a second one using UV LED strip - it's pretty useful but is at the high end - 395nm range.

The next ones (seen in pics below) is modeled after the PCI lights. These were more involved but still prety easy to put together. I made these out of the following components:

The PETG came as open tubes. To be used I needed to seal and round one end. I took a board and used a rounded router bit to create a 1/2 hole with rounded bottom. Using a hot air gun I softened the edge and pushed into hole. A couple of heat/push cycles and I have a nice sealed, rounded end. This was then cut to 18" in length.

I had ordered both white and UV (365nm) LED's (the UV ones were a bit expensive and seem to only come from china). I ordered 100 Ohm resistors to work with the LEDs to work with the 5V setup.

I had some thin galvanized wire so I used that. Two strands (pos/neg) and soldered around 18 LEDs (all in parallel) roughly spaced 1" apart. I put the resistor on the negative side of all the LEDs. The strands were then slid into the PETG tubes.

For the handles, I simply used 1" pvc - a 5.5" long piece. The length was determined by the flashlight used with enough space to hold the 5V boost chip and wiring. One end of the pvc was plugged with a wooden plug drilled with a 3/8" hole. I then used some soft copper pipeing (3/8" OD) bent to run from handle (pushed into wood plug) to PETG - it fit really well into the PETG which has 3/8" ID.

For the wiring, I used some cheap flashlights (see link below). Free with most sales at Harbor Freight. The first one fit into the pvc pipe unaltered. The second was a bit wider so had to put on my lathe and slim down. I removed the 3 AAA battery holder, and LED's/lense. I reused the LED holder to mount a positive terminal. Then some hot glue to hold the end in place. I did have to order some aluminum solder as the flashlight cases - used as the negative - are aluminum. The flashlight already has the on/off push button and the end screws on so it's easy to remove the battery to recharge it.

I connected wires to the case (negative) and to the positive terminal. These I connected to the 5V booster. This is a nice little chip that takes the 18650 voltage (3.7-4.1) and upboosts it to 5V. It will also cut out below 3.7 so the battery doesn't get too drained.

All these parts are then simply hot glued in place. This holds plenty strong but still possible to take apart if needed.

Click on any image below to view a larger (around 640x480 pixel) image.