Speaking of the D4, here is mine with its new Neodymium magnet :
I put the body and tailcap in the lathe at work and did a 15mm hole through it.
I then put a 3mm thick magnet and glued it along with the spring board with some loctite
Very elegant solution on the D4!
Iāam building a fet+1 driver now and it will go in a Skilhunt DS20 with Luxeon V2 led and AndĆŗril firmware.
Mineās a lot smaller than most of the mods in this thread, but I swapped the emitter in my Nitecore TUBE with a 95 CRI 5mm Yuji LED. Iām very happy with the results. The current limiting resistor also had to be swapped. I put in a 33 ohm resistor. This should give me about 36mA to the LED.
Not something I physically created today but I did the layout on this 15mm Utorch S1 3 channel driver. 1+4x7135+FET built for Anduril. Probably the most insane routing job Iāve ever had to do. Space was at such a premium I had to put a resistor under the Tiny85 (which has bent pins to fit on a T13 pad so itāll be slightly raised off the board)
Hereās the copper layer
I was going to suggest to drill a small hole between the pads to let R4 sink into the board, but then I saw that even in that small gap is a trace running.
Wow. 
Love your work. 
I "think" I have an S1 and would be very interested in this as well, thanx CK!!
You probably know this, but I think the most important parts are the C1 cap and the R5 resistor (4.7 before the diode). That 4.7 was the key to cleaning up the signals, DEL discovered. Not sure if the 47 ohm and 100K are that super important. Of course the diode itself is optional, but adds reverse polarity protection.
I'm not a fan of the triple channels - I prefer the simpler FET+1. I had a lot of troubles getting the FET+bank+1 ramping looking smooth and it's still not that smooth. Not sure if TK worked out the kinks in Anduril, but if she did, would love to see how. I believe, not sure, she overlaps the channel transitions which may have smoothed it out. The NarsilM FET+1 tables ramp great, but the triple has a noticeable transition. Of course to create the ramping tables, I used TK's tool, a Python script, to build them. The other major problem with triples is they use up my limited supply of eagleclaw 7135's.
Not a problem because I can still use this driver as a FET+1 with NarsilM v1.3.
I left C2 off already, now I was thinking about excluding R3 (100K FET Pull-down) cause worst case you could add it across the FETās S & G legs if it not being there ended up being detrimental somehow. Thatād let me move R4 to R3ās position getting it out from under the MCU.
I'd go by DEL's 17 mm design here: https://oshpark.com/shared_projects/qsbLVgh0
He eliminates the least needed components, C2 and the 47 ohm in line to the FET gate, but kept in the 100K. I know he had a specific order of priority and definitely that 4.7 ohm guy before the diode was very important. Before DEL's design in of the 4.7, it was hit and miss whether a 25/45/85 would work or not. Richard at MtnE had a different approach that worked but DEL's design is better, as proved on the scope.
Ohh, fyi. The classic 8x7135 ATtiny13A driver design was out of spec for the 13A, but seemed to always work. The 25/45/85's turned out to be more finicky/sensitive, so that's why the 4.7 ohm is needed -- it should have been in the classic 13A 105C/105D boards all along.
I think what Iāll do is net the two R4 pads together, that way if anything is wrong (doubtful but stillā¦) I can cut the trace and solder the resistor in place later.
Edit:
Welp Iām an idiotā¦
My first thought was 0402ās but nixed that right away. better think again
Stuck a Lexel TA driver and a Luxeon V2 (3000k) into my Wowtac A2. Got to break in my Zeny soldering station.
Follow on ā¦
Sweet. Love the centre. Did you make the adaptor?
Pinkpanda, nice stuff, will continue to what with excitment (and envy.)
Enjoyed your earlier 21700 light as well, hope you finally got some cells to power that beauty 
Reflowed a couple of SST-20 4000K 95+CRI into a CF8ā¦ now its warm and tight, the way I like it (but probably not as bright on Max.)
Yeh, I made the adaptor because I didnāt want to use the body to hold the head for turning as it is a soft metal. The head is ti.
Thanks mate. Yeh, I got a couple cells eventually for the 21700 light. Looking back now that was a pretty simple build in comparison to this one.
Another day and another pocket destroyed by my Emisar D4. Oops! Even with my switch button trim I still had an accidental pocket activation. GRRRR.
To try to protect my remaining pants from the Emisar deep fry, this time I tried something new:
Flip up switch cover for Emisar D4.
- The cover is made from 0.032ā aluminum sheet for the main piece with 0.016ā for the hinge.
- The hinge pin is a piece of copper rod I had laying around bent into the shape of a staple.
- I drilled 2 holes in the top of the head for the hinge pints. They arenāt very deep. Maybe 3 mm or so.
- I used Fiberfix optical super glue to hold the whole thing together. I accidentally got some glue on the top of the switch boot. Looks unsightly but has no affect on operation so Iāll probably leave it.
- The sides of the cover grip the sides of the head keeping the cover securly in position while closed.
- I removed the anodizing from the aluminum head so it would match the aluminum cover. I also polished the bare aluminum on both the cover and the head.
- When the cover is closed the switch cannot be depressed. The cover can be flipped up or down with a quick thumb action.
Hopefully this will protect my pants pockets from being burned.
@pinkpanda3310
Really nice work! I envy you!!!
A lathe could make things so much easier. But on the other hand it would end up in me spending much more hours now not only modding lights. No now i had to build them. Maybe i should be lucky to no longer having access to a lathe 
What is with the electronic lockout? Doesnt it have this?
The lack of anodisation is not verry good for such a flashlight at all.
I finally took a beam shot that included the Luxeon MZ build from the below quote in case anyone was curious, far right:
WB=5500K, ISO=125
Some work on the tailā¦
