I'm sure you've all seen this done before, but perhaps the part about changing the voltage difference will be interesting.
I decided to avoid any sort of mechanical modification for my first project while I get some practise working with plastic. I bought a $5 LED cluster torch from Mitre 10 and set about fitting it to the shell of the Recon's torch.
I took the LED torch apart and saw that it used a stack of 4 1.5V button cells. In what may have been a bad move, I decided to run the LED cluster from a 9V battery because it'd be easier to fit. (Apparently 9V batteries don't have great longevity, but given that it's just running LEDs, hopefully it'll last a while.) Anyway, this means that I needed to get 6V across the cluster.
Using a multimeter, I worked out that the cluster drew 100mA at 6V. Ohm's law means that it's got a resistance of 60 Ohms. To get 6V across the cluster from a 9V source, I need to put it in series with a resistor: Given that I wanted 100mA to also be drawn from the 9V source, Ohm's law meant that I needed a total of 90 Ohms of resistance, which means a 30 Ohm resistor in series with the cluster.
Fitting the cluster into the orange collar at the front of the Recon torch was a little fiddly, but doable after scraping away some plastic with a pair of scissors. The fit felt so snug that I didn't bother with glue. Then it was a straightforward job wiring up the Recon's power switch to the battery clip, resistor and LED cluster, taking care with the polarity.
Hollowing out the internals was fairly simple: I only needed to remove a couple of thin plastic pieces. I cut thin strips with a pair of scissors and ripped them out with needle-nose pliers. A pair of nail clippers tidied up all the burrs from tearing the plastic. I removed as much as I could from one side of the case and as little as possible from the other to prevent the battery from rattling around.
As you can see from the picture of the internals, I'd cut out too much plastic and had to pad the insides with cardboard to stop the battery from rattling around:
I left the old battery case in it's original place as it keeps the power switch in position. Here's what it looks like all closed up:
Comments welcome.
I decided to avoid any sort of mechanical modification for my first project while I get some practise working with plastic. I bought a $5 LED cluster torch from Mitre 10 and set about fitting it to the shell of the Recon's torch.
I took the LED torch apart and saw that it used a stack of 4 1.5V button cells. In what may have been a bad move, I decided to run the LED cluster from a 9V battery because it'd be easier to fit. (Apparently 9V batteries don't have great longevity, but given that it's just running LEDs, hopefully it'll last a while.) Anyway, this means that I needed to get 6V across the cluster.
Using a multimeter, I worked out that the cluster drew 100mA at 6V. Ohm's law means that it's got a resistance of 60 Ohms. To get 6V across the cluster from a 9V source, I need to put it in series with a resistor: Given that I wanted 100mA to also be drawn from the 9V source, Ohm's law meant that I needed a total of 90 Ohms of resistance, which means a 30 Ohm resistor in series with the cluster.
Fitting the cluster into the orange collar at the front of the Recon torch was a little fiddly, but doable after scraping away some plastic with a pair of scissors. The fit felt so snug that I didn't bother with glue. Then it was a straightforward job wiring up the Recon's power switch to the battery clip, resistor and LED cluster, taking care with the polarity.
Hollowing out the internals was fairly simple: I only needed to remove a couple of thin plastic pieces. I cut thin strips with a pair of scissors and ripped them out with needle-nose pliers. A pair of nail clippers tidied up all the burrs from tearing the plastic. I removed as much as I could from one side of the case and as little as possible from the other to prevent the battery from rattling around.
As you can see from the picture of the internals, I'd cut out too much plastic and had to pad the insides with cardboard to stop the battery from rattling around:
I left the old battery case in it's original place as it keeps the power switch in position. Here's what it looks like all closed up:
Comments welcome.