4x XPL HI SRK, C8 Reflectors

You are right! I thought these batteries are capable for what I wanted, but I tried some 10amp LG cells and the lumens are indeed going up… Thanks for the advice!

And thanks to everyone for the kind words!!!

Nice build! It reminds me of this one from Old-Lumens a while back. His is a little teensy tiny bit bigger though! :smiley:

You are right, I was inspired from his project, I will write it in my original post! It needs to be mentioned….

very nice
those reflectors, ehm that quad reflector looks very good!

That’s some heavy duty modding Kourtinoksylo! Looks very nice and looking forward to some beamshots.

Nice :+1:

Wowser! That's some nice work there Kourtinoksylo. Congrats!

I’m with ImA4Wheelr and others with their comments. This is a really nice mod. The reflectors look amazing and I admire your skills in building this wonderful light. Thanks for posting it up.
One thing, next time dont be shy in posting up lots more pictures in the fabrication process. :slight_smile:
Long live Justin. :+1:

Very nice outcome :beer:

Interested to see the output on better cells :+1:

Awesome job on the reflector(s). :+1: :+1: :+1:

No pictures. :frowning:

Just Photobucket’s “Please update your account to enable 3rd party hosting”

Great reflector job! looks very clean.

I fixed the issue with the pictures, thanks to everyone for the comments!

Great build! The C8 reflectors turned out very clean when glued. Congrats!

Nice build! It’s the first time I’ve heard of plexiglass as lens. Any particular kind of plexiglass? Or did you just use “normal” stuff that anyone can get anywhere?

Yes normal Plexiglas/Acrylic from eBay, not optic grade not AR coated just plain PMMA. I was not satisfied with the performance of AR glass from the popular websites so I tried this solution. I bought a 40cmx40cm piece, 2mm thick and I cut it in any diameter I want for any flashlight. Cost 10euros for this size.

I just did some measurments with a flashlight that I have, its output in mid mode is:
1.Without lens:……………1640lm 100%
2.Plastic Maglite lens:….1550lm 94.5%
3.AR Coated 2mm:………1525lm 93%
4.Plexiglas:…………………1592lm 97%

Even if my measurment method is false in terms of lumens, we are interested here about relative changes between different types of glass. I tested the lenses back and forth 2 times, always same results with difference of 6-10lumens, probably because of battery drain.

So I see absolutely no reason to pay 2 or 3 dollars a piece for AR coated glass and wait weeks for it to arrive. I just cut it in a matter of minutes any size I want and on top of that its better in terms of performance… As a downside I could imagine that it gets easily scratched, but you cut a new one when needed…

I’m not questioning your numbers, but something seems amiss when a Maglite lens and/or a hand-cut piece of Plexiglas can out-perform the AR coated lens. :expressionless:

The measurment is correct, I dont know however about the quality of the AR glass. Mine is 52.6mm-1.6mm from KD, described as multi AR coated. I didnt find the size in any other shop to test it. Anyway even if proper AR glass is outperforming Plexiglas it would be for 1%, for me it isnt worth the cost and wait.

What would be the light transmission rate of a good AR coates glass?

Today I did another measurment because I was also skeptical about the 93% of AR coated glass. The only other AR glass I have is one from convoy for an C8.

So: C8 with SinkPad, max mode, battery level irrelevant but almost full:

No glass: 1096lm
Original glass: 1058lm = 96.5%
AR glass: 1085lm = 99%
Cheap plexiglas: 1070lm = 97.5%

This makes sense now I think, AR is the best of all with little space for improvement. But Plexiglas is slightly better than original non-AR. In case that someone cant find AR in the size they want, Acrylic is a very good solution that can be cut in any size…
I need to apologize for this 93% I referred to yesterday, but is seems that the AR glass I ordered is of very very poor quality….they managed to do it worse then non-AR coated…

Thanks for the re-test. I trusted your numbers all along. I just didn’t trust that AR coating. It should never do worse than non-coated. That doesn’t take anything away from the relatively good performance of the Plexiglas, though. That 97.5% clarity is pretty good, and a lot cheaper than decent AR coated lenses! :+1: