Building your own light

[Avic7]

Recently at the dive shop, I got to hearing about how some people build their own light to use on a dive. One of the guys said that another diver built his own light that was stronger than a D8 flashlight and that when the guy turned on the light, it was like an underwater sun had "risen out of the water" so to speak. The only problem was that the battery pack was quite heavy (which the diver used it as part of his weights). This light he referred to was called halogen, I think... not sure if I got the right name for it. I do know some people buy it and it is quite expensive, while others have the knowhow on how to built it. I was wondering if there is anyone out there that can explain how it is built and how you build it to withstand the pressure when you take it down with you diving, as well as the supplies that you need to build it?

 

[miketsp]

Recently at the dive shop, I got to hearing about how some people build their own light to use on a dive.
..snip..
I was wondering if there is anyone out there that can explain how it is built and how you build it to withstand the pressure when you take it down with you diving, as well as the supplies that you need to build it?

You're looking in the wrong forum. Go into the DIY Forum. There are quite a few threads on this subject with a lot of detail.

..snip..
One of the guys said that another diver built his own light that was stronger than a D8 flashlight and that when the guy turned on the light, it was like an underwater sun had "risen out of the water" so to speak.
..snip..

I built my own. The first prototype had a 50W 38degree halogen bulb and a 9AH sealed gel rechargeable battery. As you say it's like being in daylight. It took all the fun out of night diving. It maybe OK for cave/wreck exploring but for normal use it was a pain. The other problem I had was that it was no use for signalling other divers. You could wave it around all over the place and the other diver didn't see any difference.
My second prototype changed to a 50W 8degree bulb. Slight improvement for signalling but still too bright. My final model had multiple halogen bulbs, a 20W 38degree for general use and the 50W 8degree for emergencies.
Total construction price is very low.

..snip..
The only problem was that the battery pack was quite heavy (which the diver used it as part of his weights).
..snip..

Sure they're heavy but as for using it as part of your weights this is rubbish. Unless you are going to construct from heavy metal tubing, most lights are close to neutral buoyancy. All mine are. The canister volume displaces a good volume of water.

 

[jonnythan]

You can buy lights like this. A D8 has a 14 watt halogen bulb.. currently the lights that are all the rage are 10 watt and 18/21 watt HID's, which have roughly the output of 50 and 100 watt halogens, respectively.

Here are some links where you can learn more:

http://halcyon.net/lights/index.shtml
http://www.salvodiving.com/lighting
http://www.diveriteexpress.com/lights/
http://www.sartek.com/acatalog/complete_lighting_systems.html

As you can see, the lights basically consist of a battery canister with a battery pack, a cord, and a waterproof lighthead. The DIY forum has a lot of people who have made their own, but it seems that in the end, if you're buying HID (HID stands for High Intensity Discharge, and throws out roughly 3-5 times the light per watt of a standard bulb), the parts cost so much it's worth it to buy pre-made. Most of the "cheap" DIY lights are 50 watt halogen lights, but that will use 5 times as much battery power as a 10 watt HID for about the same light output.

 

[MSilvia]

If you really want to build your own, I recommend getting a copy of Steve Lindblom's Dive Light Companion. It takes a book to explain it in detail to someone with a basic understanding of DIY electronics. I don't think a scubaboard thread will suffice.

 

[Avic7]

Thank you so much for the advice. I just bought a D8 so I'm not expecting to build it yet, but just curious on how it is with other poeple.
Thanks again

 

[DiverMo]

Here's a link where there are lots of homemade canister lights - mostly halogen, but there are some HID lights as well.

http://groups.msn.com/divelight