Whilst waiting for some epoxy to set on my homemade umbilical dive torch I thought I'd finally get round to putting some details about a 7 led upgrade I recently completed. I've had a few pm's about upgrading torches so this may help someone.
The base torch was a 12v 20w MR16 Halogen canister light:

The batteries were shot so I planned to replace them with 18650 Lithiums and got hold of some holders that fitted nicely into the canister with a little bit of attention from my dremel.

You'll also see in that pic the reed switch I used in this build. I attached it to the battery holders inside a bit of thin carbon tube for protection. A couple of rare earth magnets easily activated it through the torch case. The original switch hole in the back of the torch was sealed up so there was no way for water to get in.

Having calculated the battery capacity I decided to use 7 cree xp-g r5 leds, which are capable of over 300 lumens each when driven at 1.2amps. The necessary leds and the optic to go with them were ordered from Cutter in Australia: www.cutter.com.au/index.php
With that much output the light needed some serious heat sinking so i scavenged a ropey old bit of aluminium from a local boat builders and took it to Old Man Dave to lathe up. Dave did a great job on what turned out to be a right manky lump of ally and the result was a tight fitting custom heatsink. Cheers Dave
The leds would need a constant current so i ordered the right boost driver from Taskled. TaskLED Home The Hyperboost driver arrived in quick time and I adjusted the trimpot to the maximum 1.2amp output and fitted it into the recess on the back of the heatsink.
I soldered it all together and slipped the 8 3v 3000mah batteries in to the holder, grabbed a magnet and it burst into life.
Everything fit nicely back into the container and a sewed a few magnets into an elastic strap that goes round the body to activate the reed switch.
The theoretical output of the torch is 7x300lumens= 2100lumens. It won't quite be that due to loses from my terrible soldering and the lens inefficiency, but it's bloney bright for sure.
As I mentioned before I'm now working on an umbilical dive light which is based on a mag lite body and runs 3 Seoul P7 leds, which push out up to 900 lumens each. In fact it is all running on the desk already, I've just got to seal it all up and sort out the switching.
I'll post details and pics when it's done if anyone is interested.
The base torch was a 12v 20w MR16 Halogen canister light:

The batteries were shot so I planned to replace them with 18650 Lithiums and got hold of some holders that fitted nicely into the canister with a little bit of attention from my dremel.

You'll also see in that pic the reed switch I used in this build. I attached it to the battery holders inside a bit of thin carbon tube for protection. A couple of rare earth magnets easily activated it through the torch case. The original switch hole in the back of the torch was sealed up so there was no way for water to get in.

Having calculated the battery capacity I decided to use 7 cree xp-g r5 leds, which are capable of over 300 lumens each when driven at 1.2amps. The necessary leds and the optic to go with them were ordered from Cutter in Australia: www.cutter.com.au/index.php
With that much output the light needed some serious heat sinking so i scavenged a ropey old bit of aluminium from a local boat builders and took it to Old Man Dave to lathe up. Dave did a great job on what turned out to be a right manky lump of ally and the result was a tight fitting custom heatsink. Cheers Dave
The leds would need a constant current so i ordered the right boost driver from Taskled. TaskLED Home The Hyperboost driver arrived in quick time and I adjusted the trimpot to the maximum 1.2amp output and fitted it into the recess on the back of the heatsink.
I soldered it all together and slipped the 8 3v 3000mah batteries in to the holder, grabbed a magnet and it burst into life.
Everything fit nicely back into the container and a sewed a few magnets into an elastic strap that goes round the body to activate the reed switch.
The theoretical output of the torch is 7x300lumens= 2100lumens. It won't quite be that due to loses from my terrible soldering and the lens inefficiency, but it's bloney bright for sure.
As I mentioned before I'm now working on an umbilical dive light which is based on a mag lite body and runs 3 Seoul P7 leds, which push out up to 900 lumens each. In fact it is all running on the desk already, I've just got to seal it all up and sort out the switching.
I'll post details and pics when it's done if anyone is interested.
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