- Joined
- Nov 2, 2012
- Messages
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I decided to run a 2*1.5v AAA (3.0v) laser from a single 3.7v 10440 Li-ion cell, so I need a battery spacer to make the connection and take up the extra space inside the host. I decided to make my own from a brass rod and electrical tape. It was very easy to do and it seems to work well.
I went and bought a 1/4" brass rod; this one was 36" long and cost me 15 dollars. I used brass because it's heavy and will replace the weight of a battery while also acting as a spacer. But, an aluminum rod is cheaper, so it's up to you.
Two Energizer Ultimate Lithium AAA's in series measure between 3.4 and 3.5 inches in length, according to my engineering (1/50") scale. The protected Trustfire 10440 is about 1.8" long, so I measured out a 1.7" length of brass and cut it off with a hacksaw. I sanded the ends to be shiny and smoothed out the edges as well. Here is the cut rod segment compared to a 10440 and AAA.
Next I wrapped multiple layers of electrical tape around the rod segment, building up the diameter until it was obviously too large to fit into the laser host.
Then, I gradually removed sections of tape from the rod like so, until the spacer was able to fit into the host. I wanted the fit to be fairly close without risk of the spacer binding or becoming stuck. You can insulate more of the exposed metal, but the close fit should prevent any contact between the rod and the host.
Now that the spacer is the correct diameter, I installed it in the host, followed by the battery and tailcap, in the order shown.
All appears to be well; the laser is noticeably brighter with 3.7v supply than with 3.0v. I hope it doesn't shorten the diode life too much. I imagine I'll have to pay closer attention to the duty cycle now.
I went and bought a 1/4" brass rod; this one was 36" long and cost me 15 dollars. I used brass because it's heavy and will replace the weight of a battery while also acting as a spacer. But, an aluminum rod is cheaper, so it's up to you.
Two Energizer Ultimate Lithium AAA's in series measure between 3.4 and 3.5 inches in length, according to my engineering (1/50") scale. The protected Trustfire 10440 is about 1.8" long, so I measured out a 1.7" length of brass and cut it off with a hacksaw. I sanded the ends to be shiny and smoothed out the edges as well. Here is the cut rod segment compared to a 10440 and AAA.
Next I wrapped multiple layers of electrical tape around the rod segment, building up the diameter until it was obviously too large to fit into the laser host.
Then, I gradually removed sections of tape from the rod like so, until the spacer was able to fit into the host. I wanted the fit to be fairly close without risk of the spacer binding or becoming stuck. You can insulate more of the exposed metal, but the close fit should prevent any contact between the rod and the host.
Now that the spacer is the correct diameter, I installed it in the host, followed by the battery and tailcap, in the order shown.
All appears to be well; the laser is noticeably brighter with 3.7v supply than with 3.0v. I hope it doesn't shorten the diode life too much. I imagine I'll have to pay closer attention to the duty cycle now.
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