Mini-Maglite AAA with xp-e and ledil optic

Hi folks

Got a mod I'm trying to do with the minimag I have. I just need some guidance or ideas that might not come to a first-timer's mind but might be obvious for some of you. I need a way to secure the emitter which is on an 8mm mcpcb. The part of the body tube near the "switch" where the bulb plugs in is an 8mm hole exactly. The mcpcb fits neatly in there and would be perfect if I didn't need to run wires to the LED. I will probably cut gaps in the metal to run the wires through. The problem is, I want to solder the edge of the mcpcb to the metal body tube, but I don't think solder will stick to aluminum. What do I use? Should I be mounting it another way?

Also, What could I use as a switch? The light is a 2xAAA, I will only use 1 li-ion that is AAA-sized, leaving plenty of room for my driver and a switch of some sort. Are there any pre-made tail switches for the mini mag? The stock switch will be non-functional after this mod.

Sorry I don't have pictures

Bump for a related question:

I bought a cheapo dx/kd light and the star isn't even physically connected to the body. it just sits on a ledge inside the aluminum pill (I'm assuming pill means the aluminum thing that usually holds the driver and the emitter and screws into the body)

heat dispersion
I want to upgrade the emitter but I want to make sure the heat has somewhere to go.
*Is there a way to solder aluminum to aluminum?
*If not, what is a good thermal epoxy? Can I make my own thermal epoxy with high quality thermal paste and some 2-part metal epoxy like JB weld?

I was thinking of doing this with the mini mag too.
Any reply will be helpful, let those ideas fly!

This is what I used to connect HPE PCB to the ledge of Mag Solitaire,
https://www.candlepowerforums.com/threads/175600

Works well in tricky situations.

I got a sheet of 1ft x 1ft for $15.
I can split that with you if you want to try. I don't think I'll ever use up the whole square ft.

For $7.5, I'll ship 1/2 of what I have to you. (Maybe a bit less than 1/2 ft, as I didn't measure it, just based on memory, but good for plenty led jobs).

When there's plenty of room or big contact surface, I usually use DX
thermal paste, but that's often messy & doesn't work well when there's little contact space, plus often I need to add super glue after, as the paste doesn't bond very strong.

Stick the sheet to whatever you want to connect, cut around it, peel off the backing paper & connect to the other surface. I love it.

:lolsign:

That's me & I just posted right above you

The funny thing is, the xp-e I have WAS going to go into a solitaire. I was going to be the first one to do it, from what I could see, but I've never modded a flashlight, ever, so I decided to choose something with more room to work with. Yours turned out way better than mine ever would have, ma sha. A more thoughtful post on the way tonight. Trying to get some samples from 3m. do you remember the part number you got, ma sha? I'm trying to either get 9882 tape or some of their best thermal adhesive.

Ok, I'm getting a little bit of 3M's top-of-the-line thermal tape AND thermal epoxy. I will soon have a spare p4 xr-e to do some simple testing with my surplus (unless one of you fine folks with the ub3r-test setup wants to test and review this stuff. PM me with a pic of your test-sink setup if interested)

I am probably going to mount a copper sheet to the bottom of the 8mm mcpcb to help heat spread out. epoxy/tape will connect the edge of the mcpcb/copper combo board to the minimag body. For testing, I was thinking of getting a small to medium sized heatsink, try the different adhesives with an xr-e p4 being driven at 1A. an IR thermometer will be used to observe the speed at which the sink heats up. This is why I want to use a smaller sink. I will hunt through my drawer of assorted sinks and pick one I like. Anyways, that's where I'm going with this. I also will be posting up a mini-review of the 3m stuff after I organize my findings. Thanks for tuning in!

bshanahan14rulz said:

I also will be posting up a mini-review of the 3m stuff after I organize my findings.

Click to expand...

Looking forward to it! Please link from this thread.

Ok, I received all the materials I need.

Parts list:
*miniMag 2xAAA
*Cree XP-E (flux: p4 chromaticity: 7C (warm))
*8mm MCPCB from the shoppe
*Ledil Tina optic for XP-E (Offered in 3 different angles. I got the narrow angle.)
3M thermal solutions:
*9882 Thermally conductive 2mil. tape
A double-sided tacky film, white color, on a clear backing for application. the clear side is to be removed after application to first surface. Datasheet here:
http://multimedia.3m.com/mws/mediawebserver?66666UuZjcFSLXTtnxM65Xs6EVuQEcuZgVs6EVs6E666666--

*TC-2810 Thermally Conductive Adhesive
A two-part epoxy, haven't opened it yet, but it looks to be white as well, one tube is about twice the volume of the other. Datasheet here:
http://mws9.3m.com/mws/mediawebserver.dyn?6666660Zjcf6lVs6EVs66S6r9COrrrrQ-

I will have to wait until I get a camera to start building. Found out that my phone doesn't have a card slot for memory, so I don't know how to get the photos from there to computer. Perhaps I will be able to borrow somebody's phone here at work and just do all the work here...



P.S. I got way more thermal materials than I needed. These are 3m's better products and I haven't seen them tested on cpf yet. Anybody know members who have awesome test rigs? I have heatsink, infrared gun thermometer, my fingers, and assumptions about current depending on what resistor I use. If somebody wants to test this stuff more accurately than I can, reply or PM me, I will try to send you some tape and maybe some epoxy if I can find a way to package it.

bshanahan14rulz said:

...I've never modded a flashlight, ever, so I decided to choose something with more room to work with.

Click to expand...

Both the 2AAA and the 1AAA (Soli) Maglites have the same room to work with. You'll need to use a 2AA light if you really want more room.

BTW, have you seen this thread?

greenLED, My original plan was to put this xp-e in a solitaire. The solitaire is very small, though, and I have shakey hands, so I figured on the slightly larger but still compact miniMag 2xAAA. same tube size, approximately, but larger head for optics.

Ma sha's lime solitaire turned out great, didn't it!?

Ah, optics-wise! I was thinking actual "pill" size.

Looking forward to your finished mod!

Ok, I need help figuring out how to drive this LED. I have an AMC chip that is putting out around 700mA, but it gets kind of hot (when I tested it on the 12v rail with 3 LEDs in series). Would it get that hot with a Li-Ion and just one XP-E? If so, I don't have a way to heatsink a flat surface to a round tube, and no metalworking. I'm almost thinking about DDing it. Anybody want to simplify how to DD an LED? I assume you just stick a resistor in there, but how do I know what voltage to calculate with? I know what the V dropped across the led should be and how much current I want to run through it. Do I subtract Vf from 3.7 like what is listed on battery or from 4.2 to be safe? or should I just pick the middle ground and use 4V for the battery value?

Basically, which resistor:
R1=(4.2-Vf)V/0.7A
R2=(3.7-Vf)V/0.7A
R3=(4.0-Vf)V/0.7A

The mcpcb will be thermally epoxied to the body around the edges of the mcpcb (think like how puzzle pieces fit together, edge to edge) You think I could bump it up to 800 or 900mA?

The AMCs will work better than DD or a resistor, and won't heat up as much as running 3 LEDs in series from 12V. That's an apples-to-oranges comparison.

AMC7135 chips don't need to be heatsinked. They have thermal protection built in.

I actually have amc7140 http://pdf1.alldatasheet.com/datasheet-pdf/view/202790/ADDTEK/AMC7140.html

Since input range is 5-36V, I think I will go the DD route... I only have these chips because I was going to make use of the LEDs automotively originally.

hmm, I wonder, are individual amc7135 chips hard to wire? amc7140 basically you just connect LEDs to it and use a resistor to set the current. Nothing else is required.

only one thing keeping me from finishing this. ordered a AAA lithium ion with charger, made holes for wires, in the process of making/scavenging for springs. How shall I switch it? Does anybody make tail clickys specifically for mag minis?

I'm probably going to direct-drive it with resistor to set current at 700mA-ish.

Edit: So, I fried my xp-e 7C. When's that xp-g coming out?
Gives me more time to think of what to do about heat. I'm thinking of attaching a heatsink with a beveled edge at the top where the lip of the minimag body bends inwards, and putting the 8mm mcpcb/LED at the top, in the middle of that circle so that the mcpcb is flush with the beveled top of the minimag body. Wires will run through gaps, LED held in place with thermal epoxy. Heatsink will serve as a spacer/slug for heat to dissipate in.

Anybody know something that will dissolve battery acid? old alkaline leaked at some point in this light's life.