In response to the text I bolded: It’s still 10. A triple of 100-lumen emitters where each emitter puts out 10 less light (90-lumens each) is now putting out 270 lumens. 270/300=0.9, or 90. 30/300=0.1, 10.
While we are sort of on the subject (OK not really), I’ve just been looking at Ledil’s product line and it seems to me that the Sandra series can be cut down to a 35mm triple without the squished-up optics of the Cute and with less depth. (11.1mm vs 15.0mm). Assuming one was inclined to do such a thing. There isn’t an XR or XM version, but I assume that the XP version can be trimmed as described in the OP and/or using the method described by C_k elsewhere.
EDIT: While I’m writing it all down in this post… I speculate that the Cute-3 uses squished 20mm optics while the Sandra-12 uses ~16.6mm optics.
I'm not sure how much is lost, but there has to be a little bit. The issue is that the o-ring lands are there, so unless you can re-cut the groove or do without the o-ring, there isn't much. I've thought about opening it up a bit then using some silicone instead of the o-ring, but haven't tried it yet. I suppose that the easy way to test would be to measure the same driver/LED/cell combination outside the light vs. inside the light.
Wight, from the bottom of the cone to the top of the lens is 13.9mm, each round TIR within the triple is 17.3mm in diameter... near as I can tell with my cheap digital caliper.
Edit: I measured 17.4 across on the mounted one that I've polished the face of. You can see the optics better behind the polished top surface. The second measurements are from an optic that is loose but honeycombed on the surface for the diffusion.
Probably shaving off the inside of the optic meant that some light hits the shaved portion and then diffuses. Instead of reflecting off the edges of the optic and then out the front, some of this diffuse light goes out the bottom of the optic and is lost … absorbed inside the bezel.
Light will only reflect inside a TIR optic if it hits the edges of the optic at the correct angle. If it hits the wrong angle it will transmit through without reflecting.
Even though modding the optic doesn’t look like it affects the beam, perhaps it really is causing a loss of lumens.
Firelight2 is probably right, this is why I ordered the ball nose end mill bit...to get a clean cut and a rounded cut in the hopes of keeping the internal reflectors maximized.
I charged a 20R and ran the light in the light box with the bored quad optics on the now de-domed XP-L V6 2C emitters and got 2387.4 lumens.
Then I ran the light through the box again, immediately after and on the same cell, with the stock optics and got 2849.7 lumens.
So the bored optics lost 462.3 lumens. Fairly substantial, on top of the losses already accumulated from having to de-dome the XP-L's. Previous reading with the altered optics and domed emitters was 2742.75. So de-doming cost some 355.35 lumens.
In theory then, if domed emitters could fit under stock optics they should be making something in the 3200 lumen range in this light. Only theory of course, as the domed emitters just don't fit.
I worked pretty hard on this light, carving a solid copper pill/heat sink out of a bar of copper with basic tools. The BLF driver was already in this light before and running an XM-L2 just fine. So I kept it and put it in the copper pill with the quad re-flowed to the top of it.
I'm getting some flickering issues. The output in the light box is not steady, runs up and down. And I can see occasional flickering especially in low but it's there in every mode. I drilled a hole and forced a screw into the copper at the ground ring. It broke off. I soldered it to the ground ring in the light, with the solder in contact with the side of head. Same flickering.
Much as I hate to do it, I'm probably about to tear it apart and rebuild it with a new driver. Will more than likely put 4 XP-G2 S2 1D emitters in it when I do.
A Sony C5 fresh off the charger allows 14.61A to flow, while the lightbox says 2925.6 lumens. ?
That's 731.4 lumens per emitter from 3.65A to each emitter. That amperage should have the emitter up in the 1100 lumen range, being de-domed, 1300 with a dome on.
This is with a stock quad optic over de-domed XP-L V6 2C emitters. What am I missing? (Aside from 369 lumens 4 times?)
How well does lumens/amp scale downwards? If you use a lower-drain cell and get current input down to 5-10A or something does it give you the expected output?
How about trying the LEDs, MCPCB, and heatsink without an optic, lens, head, etc?
Check with welder’s goggles, are all the emitters flickering or just some?