# Supbeam K40 de-dome and resistor change.



## langham (Mar 19, 2014)

My step dad's best friend was in a motorcycle accident and he is in some pretty bad shape. I made him an awesome flashlight in order to brighten up his day...see what I did there. I de-domed the led, sanded and polished the back side of the heat-sink (this part got deleted in the infamous 2nd take). I changed out the driver and the since resistors in order to drive it harder. The light was only pushing 3.91A as seen in the video, but it will be used with gloves so I am not too worried about driving it as hard as I speculated that I wanted to. May have had to short one of the resistors in order to get it to where I wanted it to be, or use super low internal resistance batteries and run-time is what the customer is going to want. I am also one of the few advocates for lights only needing to be so bright although I will go brighter if you explicitly ask, but not otherwise. I actually like the K40 a lot, but when you directly compare it to the TN31 it does feel cheap. The TN31 actually cost me less originally as well because I got it on Thrunite's first big Christmas sale. This whole build with 4 Soshine 3400 mAh batteries and a Nitcore intelligent charger was $200 and that is with the $40 shipping from Canada on the light and Alabama state tax. The light didn't have the full 5 brightness settings on either the stock driver or in the one that I got directly from Supbeam last year. This is annoying and I will have to individually test each component in those two circuits as compared to my TN31 to see where they screwed it up. The head of the Supbeam K40 is made of thinner material, although it does have more surface area. The K40 does not have a stainless steel bezel, not sure how I feel about this as I baby my TN31 and can't imagine ever using it to bash someone in the face. That is what the pictured L2T if for. If you have the time you can watch all 5 videos and maybe you will learn something, if not then make your own video and share the wealth of your knowledge.


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## langham (Mar 19, 2014)

The pictured multimeter is a UNI-T UT60F DX SKU: 168788. The precision screwdrivers were from Lowes. The Soshines were from IlluminationSupply. Resistors are from DigiKey. Soldering materials all from RadioShack I just needed them quick I would actually recommend getting them off the internet, more bang for your buck. You should purchase 63/37 solder that is not lead free, but like I said I just made a trip to RadioShack and that spool has lasted a very long time. The thermal compound is from illuminationsupply. The spare driver was bought from Supbeam by talking to the sales rep that I normally talk to, they are normally very understanding. I got the K40 off of e-bay as well as the L2T. The Skyray S-R5 is from focalprice, although they are out (I also said this incorrectly in the video, my bad). The flash shirt is from Target. I can tell you where I got anything else as well if you would like. Thank you for watching.


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