Are people still using this T-25 torx bit method to open up XP-G optics for XP-L’s? I’m considering taking a Revtronic (Nitefighter) BT40s and swapping the stock XP-G2 emitters for XP-L2’s (and I don’t think replacement optics are available for this light). Originally I was going to go with XP-G3’s, but I’m not tempted to try the new XP-L2’s.
Thanks,
-Garry
Hi Garry, yes I'm still using it as I am sure many others are. I would be cautious trying to modify any non-replaceable optics. The XP-L2 will just fit into a few of the TIR optics without any modification, so you might be able to give that a try. Of course, the XP-L2 will give you a floodier beam than XP-L HI or XP-G2/G3/Nichia 219.
Not tempted or now tempted? It’s a good idea for starters but I think a means of polishing or at least getting closer to frosted than a coarse grind will be less costly in lumens mislaid. I’ve had reasonable results attaching small pieces of fine grit to dremel bits for lapping recesses in pills so maybe a small drill bit with some tape and 600 or better w/d paper could improve things after the torx opens it up. Final polish with a q-tip mounted in a drill and some headlight lens clarifying compound. I’d give something along those lines a try.
Plastic heats up quickly under friction and you lose everything gained and have to start over if it melts so go slowly and lubricate/clean the paper frequently. You need to be very careful of bottoming out in the recess as that is a*much* harder spot to polish. I did a few optics to fit the old P7’s back in the day and that’s all I remember of the pitfalls.
Thanks RMM. I have a 2nd optic I can test with that came with the light (a “wide” optic that I’ll never use). I’ll try a test fit first though with both optics. I was leaning towards XP-L2 now just for more lumens over the XP-G3. Driving each emitter at 1A, maybe 1.5A.
-Garry
When Richard first talked about using the Torx bit I found and purchased a ball nosed end mill bit with 4 flutes. I’ve found that if I use it by hand, going forward AND backwards, it leaves a nice smooth finish that works pretty well. If I put it in a drill and spin it up then it leaves a set of marks from chatter. The much slower hand work method worked best for me, leaving a round profile that closely matches the dome on the XP-L with a Khatod quad optic. (still a lot of lumens loss though)
I’ve got 4 of the XP-L2’s under a Carclo quad without modification in a MecArmy PT16 and it works well. So far, ~2300 lumens out of an Efest V2 16340 cell. (5.5A at the tail) 
Try chucking the end mill in your lathe. Some good double sided tape should hold the optic to your tool post well enough. Then run the lathe in low and feed the optic into it slowly with lots of coolant.
Definitely a much nicer solution...but a bit more expensive than $0.25. 
Hey, Dale already spent the money, might as well try it.
I guess this mod is for older xp-l’s right ?
The xpl v6 and xpl2 i have fit Carclo without issues .
The XP-L V6 typically does not fit the Carclo series, even if it might appear to do so. The pressure causes delamination of the dome and if the light is taken apart many times the domes will stay stuck inside the TIR and the bond wires will be damaged. As will almost everything, ALWAYS and NEVER are bad words to use. A high percentage of the time the emitter will be damaged when using domed XP-L V6 emitters with Carclo triple or quad optics.
They’re only a couple bucks, but if you can find a ball nose burr it should cut a little bit cleaner - you should peck drill to make sure you are not “recutting” any plastic or rubbing it into the surface. An endmill would tend to pull the lens up into it unless you make a fixture for it. You may be able to find a downcut ballnose endmill which would alleviate that.
Now I just move to the Samsung LH351D and don’t worry about the optics. 
Mo powah, better tint, better profile… it’s all good! 