Changing a Cree emitter in a Fenix

I'd like to change the emitter in a Fenix L1-D from the stock white Cree to a red Cree. I did some searching, but have some concerns.

I have opened (unscrewed) the head and that gives ready access to the emitter. It appears to glued down to the aluminum with what I would assume is thermal epoxy.



How best to remove the white emitter?

How best to install the new red emitter?

What concerns do you have? When I changed out one of mine, I cleaned off the epoxy covering the wires, desoldered them, then popped the emitter off with a small screwdriver. Before installing the emitter put a dab of solder on the pos and neg contacts where the wires are going to connect. This way there's no chance of the solder connecting to the heatsink when soldering and causing a short. I then cleaned up the heatsink surface and reinstalled with thermal epoxy. Then you can hold the wire to the contact put some heat on it and it's done.

I'm concerned about how best to remove the glue. It'd be nice (but not necessary) to prevent damaging the original emitter and certainly to prevent damage to anything else.

I'm wondering whether the emitter needs to be insulated from the aluminum substrate. If it does, how best to keep it insulated while insuring good thermal conduction. It'd be nice to be able to remove the new emitter if I decide to replace it. This is likely since the emitter I got is not really from the bin I want and I hope to be able to get a better one down the road.

I'm questioning whether centering the emitter is going to be an issue or if the well in the aluminum substrate is a tight enough fit that it will self-center it properly.

I've found two-part thermal epoxies in the past, but I wonder if there is something out there that this forum's wisdom may be able to suggest that is more optimal for the job. Perhaps something that will make it easier to remove the new one.



Thanks in advance.

I'm very interested to see what this red Cree will do in the Fenix head. I bought a seven LED red AA light from Peak, but I'm very underwhelmed by its output and it's not adjustable (it's too dim for me to care about adjustable anyway). I've been wanting a red led 1XAA light with adjustable output, really good throw (for a AA) and reasonable spill, and there just isn't anything I've found that meets the bill, so it seems dropping a red Cree into a Fenix L1D may be my best approach. I'm quite experienced with building/modifying electronic stuff and have access to very good tools and technicians with better skills than I if necessary.

1. I used a dental pic and acetone. The acetone seemed to soften up the epoxy some. I poured a little bit in the well and let it sit awhile.

2. No insulation necessary, the emitter sits on a little pedestal inside the well and there is no electrical contact.

3. The emitter fits pretty tight inside the well, no room to move for centering. I think it's made this way for fast assembly with no need to manually center. It can be centered or off a little. What I did is place the emitter on the pedestal in the position I was to epoxy it and screw the head on to check for centering. If the emitter needed moving, I filed a little off one of the ceramic base corners, depending which way I wanted to go with it.

4. If you don't put a half a tube of epoxy on it, like Fenix did, it will be easy to remove the emitter you install. I just put a dab on the pedestal and pushed down to spread it out.

Good stuff, thanks.


Any suggestions on specific adhesive?

I used Artic Alumina two part epoxy.

I got the old one off! No worries.....

I managed to drop in a red Cree and it lights up nice, but unfortunately, the regulation circuit doesn't appear to want to go low enough to be able to dim the light.


I had nothing but supplier slowness when it came to getting the Arctic Alumina and bailed on that and just got some thermal epoxy from McMaster Carr, but I'm sure it's good enough...