Looking for someone with experience to custom build me a flashlight
First, a little background on myself. I am a security dog handler, I patrol all manner of sites with my rottweiler. I always carry three torches. 1. A 4-D cell maglite with LED bulb, 2. A 500 lumen 3 x cree led torch powered by 4 cr123a batteries (1000mAh, rechargeable), and 3. a 100 lumen cree led torch powered by a single AA battery.
I carry the maglite mainly to use as a secondary defence weapon should my dog be incapacitated by an intruder (thankfully it has never come to this, or indeed a dog bite yet which is not bad for a 5½ year track record). However, the light is produces is pitiful for it's immense weight. The 100 lumen torch is more or less my "if all else fails" backup, used in emergencies like battery failure on my other torches. My 500 lumen torch is very good, it does however had a few problems - it has three modes, bright, energy save, and rapid flashing- this flashing setting drives me nuts! I am looking for a flashlight to be custom built to my specifications which will hopefully replace both the maglite and 500 lumen torch.
Size: I would like the torch to be about the same size and shape as a 4 D-cell maglite, identical to within ½" if possible so it still fits onto my belt clip.
Durability: Sky high! It will need to be made from extremely durable materials - aircraft grade aluminium for the body and head, durable plastic for the lens. My torches tend to suffer a lot of abuse over the years - being dropped by cold / gloved hands, coming lose and rolling about in the back of the van etc - you get the idea. Ideally I would like everything housed within a 4 D-cell maglite body as my current maglite has been going strong for 4 years now and apart from many scratches and dents is still perfect. This may, however not be possible due to the battery requirements....
Light: CREE is shortly bringing out a new led (called the CREE XLamp MC-E)which has me rather excited. At 750mA (maximum input) each led will output 790 lumens. I would like this torch to run four four of these leds, giving a potential output of 3160 lumens. After doing some research there is a chance that an led driver capable of distributing 3000mA of power does not exist, but I could equally have been looking in the wrong place as I have never researched this before. These will of course require a custom built reflector, regardless of torch body.
Batteries: I would like it to be powered by 9 x RECHARGEABLE 3.7 Volt lithium 18650 2400mAh batteries, mounted in three sets of three, providing either 11.1v when set in series for a total of 21600mAh. In theory it should give us a potential runtime of just over 7 hours, but in reality I would expect the power drain from the led driver to give us considerably less, possibly 3-5 hours, however an hour or above would be acceptable. (This information may be totally inaccurate though, I just divided the total 21600 by 3000 the maximum drain). 3.7v 18650 batteries are commonly used in laptops and are suited to high rates of drain. They are the same width as cr123a batteries and twice as long, but with almost 2½ times the capacity of my current 1000mAh rechargeable cr123a. A custom battery caddy would need to be built to hold these and would need to sit within the torch body without rattling. I have a feeling that with a 3A power drain these will perform better than 4 rechargeable D cells or 12 rechargeable AA cells. I am however open to suggestions.
Torch Settings: This part is optional, however I will be willing to pay more for the finished flashlight if these features can be included. As the CREE XLamp MC-E are technically four led cores in one small chip, each core within them can be lit individually. Because of this I would like four brightness settings on the torch. 1. All leds lit, 2. 3/4 of each led lit, 3. 1/2 of each led lit, 4. 1/4 of each led lit. If possible I would also like to be able to choose to send 750mAh to each led, of just half the power at 350mAh for a better lumens per watt rating. This would in effect give us 8 settings. I believe this could easily be done my three switches. 1. Master On/Off, 2. Full Power (750mAh) or Half Power (350mAh) selector switch, and 3. A sliding switch to choose how much of each led to light. This may however be an electronic nightmare, so I would be willing to settle for a full / half power setting, but natrually I would pay less for this than I would for a flashlight with all my settings.
Heat dissipation: This torch is likely to need a heat sink of sorts, not having used so many leds before I do not know how much heat they will generate. I would prefer that this flashlight not get above 90-100 degrees (Fahrenheit) when on full load if possible to prevent accidental burn injuries to myself and the dog.
If you believe yourself capable of taking on my challenge and building this flashlight I would be very interested to hear your estimates on price. Please only quote if you are prepared to also build if I accept your quote! Please note I the flashlight will need to be shipped to the UK (as a gift to prevent customs charges!), I would prefer it if you "sold" it to me through ebay once it is completed (use a buy it now, private auction) so I have some form of fraud protection, I would also require a receipt for tax purposes (I can claim a percentage back as I run my own business). Payment will be made through paypal, I am also willing to provide a small advance to help cover the costs of materials if you are a well known member and can get enough people on the forum to vouch for you. Since you will be the designer, and patents / copyrights on the flashlight will belong to
you - I simply want a torch that will replace my 4 D Cell maglite and give me more than enough light for any situation I find myself in. If you require any more information please feel free to ask me!
CREE XLamp MC-E http://www.cree.com/products/xlamp_mce.asp
First, a little background on myself. I am a security dog handler, I patrol all manner of sites with my rottweiler. I always carry three torches. 1. A 4-D cell maglite with LED bulb, 2. A 500 lumen 3 x cree led torch powered by 4 cr123a batteries (1000mAh, rechargeable), and 3. a 100 lumen cree led torch powered by a single AA battery.
I carry the maglite mainly to use as a secondary defence weapon should my dog be incapacitated by an intruder (thankfully it has never come to this, or indeed a dog bite yet which is not bad for a 5½ year track record). However, the light is produces is pitiful for it's immense weight. The 100 lumen torch is more or less my "if all else fails" backup, used in emergencies like battery failure on my other torches. My 500 lumen torch is very good, it does however had a few problems - it has three modes, bright, energy save, and rapid flashing- this flashing setting drives me nuts! I am looking for a flashlight to be custom built to my specifications which will hopefully replace both the maglite and 500 lumen torch.
Size: I would like the torch to be about the same size and shape as a 4 D-cell maglite, identical to within ½" if possible so it still fits onto my belt clip.
Durability: Sky high! It will need to be made from extremely durable materials - aircraft grade aluminium for the body and head, durable plastic for the lens. My torches tend to suffer a lot of abuse over the years - being dropped by cold / gloved hands, coming lose and rolling about in the back of the van etc - you get the idea. Ideally I would like everything housed within a 4 D-cell maglite body as my current maglite has been going strong for 4 years now and apart from many scratches and dents is still perfect. This may, however not be possible due to the battery requirements....
Light: CREE is shortly bringing out a new led (called the CREE XLamp MC-E)which has me rather excited. At 750mA (maximum input) each led will output 790 lumens. I would like this torch to run four four of these leds, giving a potential output of 3160 lumens. After doing some research there is a chance that an led driver capable of distributing 3000mA of power does not exist, but I could equally have been looking in the wrong place as I have never researched this before. These will of course require a custom built reflector, regardless of torch body.
Batteries: I would like it to be powered by 9 x RECHARGEABLE 3.7 Volt lithium 18650 2400mAh batteries, mounted in three sets of three, providing either 11.1v when set in series for a total of 21600mAh. In theory it should give us a potential runtime of just over 7 hours, but in reality I would expect the power drain from the led driver to give us considerably less, possibly 3-5 hours, however an hour or above would be acceptable. (This information may be totally inaccurate though, I just divided the total 21600 by 3000 the maximum drain). 3.7v 18650 batteries are commonly used in laptops and are suited to high rates of drain. They are the same width as cr123a batteries and twice as long, but with almost 2½ times the capacity of my current 1000mAh rechargeable cr123a. A custom battery caddy would need to be built to hold these and would need to sit within the torch body without rattling. I have a feeling that with a 3A power drain these will perform better than 4 rechargeable D cells or 12 rechargeable AA cells. I am however open to suggestions.
Torch Settings: This part is optional, however I will be willing to pay more for the finished flashlight if these features can be included. As the CREE XLamp MC-E are technically four led cores in one small chip, each core within them can be lit individually. Because of this I would like four brightness settings on the torch. 1. All leds lit, 2. 3/4 of each led lit, 3. 1/2 of each led lit, 4. 1/4 of each led lit. If possible I would also like to be able to choose to send 750mAh to each led, of just half the power at 350mAh for a better lumens per watt rating. This would in effect give us 8 settings. I believe this could easily be done my three switches. 1. Master On/Off, 2. Full Power (750mAh) or Half Power (350mAh) selector switch, and 3. A sliding switch to choose how much of each led to light. This may however be an electronic nightmare, so I would be willing to settle for a full / half power setting, but natrually I would pay less for this than I would for a flashlight with all my settings.
Heat dissipation: This torch is likely to need a heat sink of sorts, not having used so many leds before I do not know how much heat they will generate. I would prefer that this flashlight not get above 90-100 degrees (Fahrenheit) when on full load if possible to prevent accidental burn injuries to myself and the dog.
If you believe yourself capable of taking on my challenge and building this flashlight I would be very interested to hear your estimates on price. Please only quote if you are prepared to also build if I accept your quote! Please note I the flashlight will need to be shipped to the UK (as a gift to prevent customs charges!), I would prefer it if you "sold" it to me through ebay once it is completed (use a buy it now, private auction) so I have some form of fraud protection, I would also require a receipt for tax purposes (I can claim a percentage back as I run my own business). Payment will be made through paypal, I am also willing to provide a small advance to help cover the costs of materials if you are a well known member and can get enough people on the forum to vouch for you. Since you will be the designer, and patents / copyrights on the flashlight will belong to
you - I simply want a torch that will replace my 4 D Cell maglite and give me more than enough light for any situation I find myself in. If you require any more information please feel free to ask me!
CREE XLamp MC-E http://www.cree.com/products/xlamp_mce.asp
) that if you had 9 cells at 2400mAh each no matter what the configuration you would get the sum total of all the component parts (ie 21600mAh). So out of interest, does that mean that if I ran the nine batteries in series I would get the full 21600mAh? I'm scientifically minded and can't quite get my head around that... Theoretically that would surely mean I would get 7200mAh from three cells in series too? If that is the case (which I simply cannot understand lol) what is the benefit of the extra cells in parallel? Where does the extra 14400mAh that I would have had go?
