What’s your problem? Your a big man behind a computer screen. Just so you know I’m not building a flounder light. Have you ever even used one or did you have to do research to find out what one was. If you don’t want to help that’s fine but keep your smart * comments to yourself.
Ahhh, so if it’s not a flounder light…. Listen- we don’t help people build flashlights for strange sex stuff. Not that there’s anything wrong with that- what you do on your own time is your own business. This is just a PG rated forum, so all of the lights are for external use only. You are on the right track by flaring one of the ends though- safety first all the way.
Lol. You said sex
What everyone’s problem. If you have to know I’m building a midievil light pole for my son… Oh and by the way he’s dieing of cancer so time is a little bit of an issue. You get on these boards and act like your somebody special without any regulars to what’s going on I someone else’s life. Lets hope if your ever in my situation people don’t act the same towards you.
Relax, ignore people who offend you, take a deep breath and we’ll try and help you. I’m pretty regular but just came across this thread while waiting on laundry. Modding is finicky stuff and the more detail you can provide the better the responses will be. To run 3 XML in series for 5 hours you will need to supply 3A per XML for 5 hours or 45 Ahrs and maintain a minimum voltage of > 9V or 405Whrs. A nimh cell is considered depleted at 1V. It would take 41-10Ahr nimh D cells to supply that power. Nimh D cells weigh ~170g each x 41 = ~7 kilos or 15lbs. The Taskled Hyperboost only goes up to 48V input and 41 fully charged nimh cells would top out at over 55V so I would add 3 more cells and divide them into 4 parallel wired strings of 11 cells each and use a Taskled B3flex. It is a buck driver and is more efficient the closer the output voltage is to the input voltage. Even better would be 5 strings of 10. You need the extra because even a very good driver will lose 5-10% of input power as waste heat. A D cell is ~61mm long. 50 of them will fill a tube a bit over 3 meters long. I’m not trying to discourage you but just attempting to put some parameters on this for discussion. If it is not on all the time or is not on HIGH the entire time you can eliminate enough cells to make it more affordable and less heavy. Taskled flex drivers require a momentary switch(normally closed) to operate. These are readily available at Mouser, Digikey, or your local electronics store. As a first project this is ambitious but doable if you spend a little time on it.
You mean 15 Ahrs
Yeah, 15 ahrs or 45 whs.
Sorry, but you have 9 Volts and 15 Ahrs, that’s 135 Whrs 
The only reason I was wanting to do 3 XM-L is because my son thought they looked cool. It sounds like 1 XM-L will be a lot easier.
Nightcrawl——- I have a DMM and I would prefer to keep the battery’s simple. I found a Tenergy battery, will that work for my application? The light will not be submerged in water but I want it to be water proof anyways, you never know what a kid is gonna do and I would like this to be as bullet proof as possible.
Rufusbduck——- I know your not trying to discourage me and I appreciate your help. When I told my son I could make the spear I figured the hard part would be the machining. I have electrical knowledge but its in high voltage. If there is a way I can buy everything ready to go so all I have to do is assemble it in the pole that would be preferred. My son loves the look of carbon fiber so that’s what im getting the pole made of. When the light portion is figured out I have to send the carbon company the LED reflector so they can take measurements and flare the end properly.
Im not expecting anyone to build this project for me but this is a little out of my expertise. All I was hoping for was to gain knowledge from people that are experienced building lights.
Welcome to your new home, billnye!
@Custom Candle: See, now that is a cool project. If you had posted that right away, I bet a lot of people would have jumped on in. Great idea.
What I dont really understand is why this thing should put out a lot of light. If you want to attend festivals (probably at night) 3 properly driven XMLs are way too bright.
But it all sounds doable. Those Tenergy cells are LiFePo cells and those are almost as safe and easy to treat as NiMH cells. But you will still need an extra charger. You can do the same with 3 to 6 NiMH cells, also available in D-size. Thats a little bit more.
Also, if the "rod" of this light pole will be made of carbon, you have to find a way to get the negative end of the cells to the top, running a wire or sth like that in it.
Oops! It was late. As usual. I was adding them in parallel. So anyway a 5’ stick should have plenty if room but you would still want to load it with strings of 9-10 cells.
Ok here is what I think I need
batteries—— If I understand right this will give me 6 to 8 hours run time. Tenergy or Tenergy D 10000mAh
driver/LED—— (XM-L SINGLE OR 3 MODE) Im still not clear if I can use a dropin or not
host—— (custom carbon fiber pole “Hollow”)
charger—— Tenergy Smart Universal Charger
heatsink/other materials——— Please clarify on heat sink/other material
That stick should be perfect for a single XML. Maybe you could cast the spear head out of clear resin and illuminate it from the inside. A 105C driver like This One from illumination supply and can be modified for single mode(high only) output. There are cheaper ones that often take a month or more to arrive. It will work with a simple on- off switch that can handle 3A and 5V. This thread offers an introduction to this type of driver Put the switch and batteries in the middle to make it balance and the driver and led at the end of some aluminum or copper pipe(more surface area than an equivalent weight of solid stock) that slips inside the pole. Alternatively, you could machine the heat sink/led mount as a collar that fits between the spear head and shaft and holds the two together. I would do the led part first and then place the batteries for balance. This is a neat project. I hope you can work through the details and see it done.