LED Zeppelin
Flashlight Enthusiast
This is a method of adding a resistored 2-stage to a twisty light by means of a spring module attached to the battery button.
Shown are a CR2 and a CR123 version. My first attempt was the CR2 which I made from modifying a McE2S board with surface mounted resistors. I sanded the board as thin as possible, and drilled out the center to accomodate the cell button. I also had to devise a means of contacting the cell, so I wrapped some wire around the center hole of the board. Not pretty but it works. You can see the wire in the 3rd picture which shows the bottoms of the modules.
I also added a spring tab made from a section of a wavy washer. This was soldered to the top of the board. The spring tab contacts both inner and outer sections of the board, so I cut out sections of the inner board contact ring to isolate the tab, and soldered it to the outer ring.
In operation, current flows through the spring tab, through the resistors, and to the cell via the wound wire at the center. Continued twisting compresses the tab against the cell for direct contact and full current.
The second incarnation used a plastic flanged washer cut from a pneumatic cylinder port plug - the plugs that seal the ports when they are shipped new. I always wondered why I saved them.
I cut the center of the plug out, and trimmed the flange as shown, then made a spring that seated on the flange with a solder blob at the top. I filed the spring/blob as thin as possible. The spring is insulated from the cell by the washer. Then I soldered a resistor to the base of the spring which crossed over to the underside of the washer, and heat-staked it into the bottom.
The theory is that at first the light (+) contact touches the end of the spring, and current flows through the resistor to the cell face. Upon further compression, the spring bottoms out on the cell button and shorts the resistor for full power.
In order to contact the cell, and for additional clearance for the device, I pried out the insulating washer at the end of the CR123 cell. Be careful not to short the cell when doing this. Thus the one end of the resistor that wraps under the module is in contact with the face of the cell, not the button.
I made this device some time ago, and it was penned the "Battery Command". I'll refer to it as the BC+, since I made some that were for the (-) end of the cell, but these are better.
For this to work properly in a twisty light, there are a couple points I should mention:
- The light should have enough threading allowance to add the thickness of the BC+ without compromising the seal. The thickness added by the BC+ is basically the thickness of the spring wire/blob at the end, plus the gap between it and the cell button.
- The (+) terminal of the light should have a raised blob to contact the BC+ spring/blob.
- The light should not have anti-rattle foam donut, or it should be weak and easily compressed. If the donut is too firm, the BC+ spring will collapse before the donut and you'll only get hi.
These are nice since you don't need to modify, or couldn't if you tried, all your twisty lights. You simply transfer the BC+ from light to light, and cell to cell.
Shown are a CR2 and a CR123 version. My first attempt was the CR2 which I made from modifying a McE2S board with surface mounted resistors. I sanded the board as thin as possible, and drilled out the center to accomodate the cell button. I also had to devise a means of contacting the cell, so I wrapped some wire around the center hole of the board. Not pretty but it works. You can see the wire in the 3rd picture which shows the bottoms of the modules.
I also added a spring tab made from a section of a wavy washer. This was soldered to the top of the board. The spring tab contacts both inner and outer sections of the board, so I cut out sections of the inner board contact ring to isolate the tab, and soldered it to the outer ring.
In operation, current flows through the spring tab, through the resistors, and to the cell via the wound wire at the center. Continued twisting compresses the tab against the cell for direct contact and full current.
The second incarnation used a plastic flanged washer cut from a pneumatic cylinder port plug - the plugs that seal the ports when they are shipped new. I always wondered why I saved them.
I cut the center of the plug out, and trimmed the flange as shown, then made a spring that seated on the flange with a solder blob at the top. I filed the spring/blob as thin as possible. The spring is insulated from the cell by the washer. Then I soldered a resistor to the base of the spring which crossed over to the underside of the washer, and heat-staked it into the bottom.
The theory is that at first the light (+) contact touches the end of the spring, and current flows through the resistor to the cell face. Upon further compression, the spring bottoms out on the cell button and shorts the resistor for full power.
In order to contact the cell, and for additional clearance for the device, I pried out the insulating washer at the end of the CR123 cell. Be careful not to short the cell when doing this. Thus the one end of the resistor that wraps under the module is in contact with the face of the cell, not the button.
I made this device some time ago, and it was penned the "Battery Command". I'll refer to it as the BC+, since I made some that were for the (-) end of the cell, but these are better.
For this to work properly in a twisty light, there are a couple points I should mention:
- The light should have enough threading allowance to add the thickness of the BC+ without compromising the seal. The thickness added by the BC+ is basically the thickness of the spring wire/blob at the end, plus the gap between it and the cell button.
- The (+) terminal of the light should have a raised blob to contact the BC+ spring/blob.
- The light should not have anti-rattle foam donut, or it should be weak and easily compressed. If the donut is too firm, the BC+ spring will collapse before the donut and you'll only get hi.
These are nice since you don't need to modify, or couldn't if you tried, all your twisty lights. You simply transfer the BC+ from light to light, and cell to cell.
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