Fenix TK61 teardown and mod thread

How do you guys solder these resistors on? I was told at the local electronic store if I use a soldering iron it will fry the resistor. They said I need some kind of special heat gun?

Welcome to the twilight zone. Its called a hot air rework station I believe. But its not required. The guys (and gals) here have been doing it with soldering irons for ages. They do so daily. They dont just solder them on to new boards, they stack them.

Maybe someone should tell them they cant do it.

A youtube clip from this thread… soldering resistors
http://www.youtube.com/watch?feature=player_embedded&v=214kSNaBD3A

Lol of course you can hand solder the resistors. The same temperature is needed using hot air to melt the solder as is needed from the tip of your iron, the only difference is the source of the heat.

Well I guess with a steady enough hand I could do it maybe after a beer it would be easier. One more quick question. I am planning on doing the tk61 resistor mod with the R030 resistor but can’t seem to find any that look like the picture. Is that 30ohms or 30mohms?

Well, I’m an idiot just figured out its .030 ohms right?

Welcome to the forum jcminar. You're correct, .03 ohms. The "R" is the equivalent of a decimal point.

Where can I find these .030 ohm resistors what’s the watt on these things people keep asking me. And would a .028 or .033 be ok?

There are a few options on these, so it can get a bit complicated to those of us that aren’t into electronics. The package size is important, it determines how long and wide the resistor is. I once ordered some that were backwards, wide instead of long. It was relatively easy to make it work but it covered the entire stack of 3 normal resistors to do so.

I still haven’t figured out how important the wattage rating is, I usually go for the higher rating but don’t know if it’s necessary.

.028 or .033 should be fine, very close to the .030 you’re looking at and as such would make a very small difference, probably only measurable and not noticeable to the eye.

I intend to try an R025.

I used an online resistor calculator to figure out the end resistance when stacking…the 2 R050 give a net of .25, with an R030 on top of 2 R050 the net result is 13.63636364, with an R025 instead, it would be 12.5. By going with 2 R030’s the net went down to 9.375 and if 2 R025’s were used it would be 8.33. So I’m thinking it should handle the R025 ok, but not 2 of em.

My primary reason for using the R025 is because I already have some. Should know how it works in the next hour or so, as my light is due in today.

DigiKey or Mouser are likely places here in the states.

I kinda figured the difference in ohms would be ok and since wattage doesn’t really matter I guess now all I need to do is find a place that sells them. Thanks for all the help.

The have a standard USPS rate of $5 or so shipping, so if you’re only getting a few resistors for pennies, the shipping is steep. Check to see if there’s other stuff you need, maybe some emitters, to offset the costs.

Vinhd send me some R050’s and transistors, my friend will do the mod for me in few days, i will report back how much amps to the led, and how are the heatsinking-output figures.

3 of these parallel will equal about .033 ohms. 1206 size resistors are typically 1/4 watt rated.

I stopped in at my local electronics store and all they had were .05ohm resistors with the numbers 000 if I put this on will it damage the light or not do anything at all?

000 is not a resistor, it is a “jumper”, you would get same results if you put just regular wire across the pads where you thought to solder 000.
If you want 0.05 ohms resistor then you need to find the one marked with R05.

Try to buy one with matching size to what you’re stacking on to make soldering neater. The one you linked is 3.2x1.6mm. I’m not sure what you already have.

Where the heck can I find one of these things? I’ve been all over the internet and forums and can’t seem to find any information anywhere…

jcminar, since you posted here. Ill just answer here instead of PM. Sorry to hear about that your meter slipped and caused the blowout.

The last guy who had issues with the C012C I guided to RMM/Mountain Electronics LLC. Not sure what resulted it.

In total I know of two people who have fried the C012C. Im guessing the other guys had some sort of slip up too.

Dale also had issues, but did not break anything.

Im just putting the info here as a warning. Be careful, and don't risk modding something you don't have a backup solution for.

I know many have had great success. For some reason this mod have gained some popularity, and seems to have attracted several who wants to mod their 100$+ light without much mod experience (Ive gotten PM`s from several people Ive never heard of).

Ive been thinking of making a thread on the TK75, with some pictures and various test results from modding. But im not sure how wise that is anymore. I know many people have gotten great help from this thread, but a few have had issues.

I might have a TK61 driver for sale in the future in case someone is in need of one. My replacement option for the stock driver have been heavily delayed, so I will keep my modified TK61 driver for now. RMM might have a high current driver replacement option in the future too?? Probably before mine is modded for stage "2", or stage "3"...

Vihn’s Variant 2 is out. TK61vn V2 - Throw King +740K Lux ;-) | Candle Power Flashlight Forum
:open_mouth:

Sounds like its got a STAR firmware.

RMM, is there is connection between what you and vinh are doing?

The transistor mod took about 5 minutes worked great slipped on my meter and hit the wrong contact while checking current. Anyways, ordered some replacement transistors should have it up and running in a few days. I’m still a little puzzled as to why this transistor blew. I know I must have moved the probs on the dmm accidently and shorted but why would that burn up a resistor? I didn’t think the meter put out any power? Btw the light still worked but only on low mode with that transistor blown.