Credit due to user Kai_159 on r/flashlight; here’s the post. Huge thanks for taking and labeling these photos, and for the permission to share this on BLF–I wanted to do this given how difficult it is to search reddit.
Great googly moogly, this is incredibly useful. Thank you for posting this.
2 Thanks
Nice!!
Recently I got an 15 degree beaded and was surprised with its beautiful look!
Now I don’t need to buy ALL of them to check (:
1 Thank
Exactly the sort of stuff I needed this for! I found out from other sources about the 15 and 30deg optics having a sunflower diffusion pattern, so I got them and couldn’t be happier. The 30deg, in particular, might be my favorite right now: good flood, usable throw, no tint shift. Incidentally, I believe the same optic is being used in some Skilhunt lights.
And as we see from the beamshots, the nominal angle often does not correlate with the actual beam shape!
2 Thanks
Has anyone noticed that with the 21mm variant the tir itself sits directly on the corners of 5050 LEDs?
I suspected the white housing with its square opening to act like a gasket, spacing the tir just right not to exert any force onto the top of the led when screwing down the bezel. But after test fitting one onto an SFT-70 on a 16mm MCPCB I noticed that the bottom of the white housing doesn’t even touch the MCPCB.
Here’s a reddit post that shows a damaged XHP50.3 HI probably because of that issue/design error: https://www.reddit.com/r/flashlight/s/gftCIhd9eW
This comment mentions sanding the bottom of the tir in order for it not to sit on the LED and to just overall fit better.
I’ve also seen @QReciprocity42 use a 9mm 5050 gasket in combination with the bare tir, would that be the most elegant solution to this problem?
1 Thank
Thanks for bringing this up! I currently EDC a S2+ SFT70 with the 30deg beaded variant of this TIR, and did run into this issue of TIR sitting directly on the corners of the LED. This is certainly not good, but didn’t cause me any real issues aside from a tiny bit of initial plastic dust. It’s not nearly as bad as Convoy’s circular-opening centering gaskets grinding on the LED corners–in this TIR situation the TIR rests on top of the LED corners, which are much less sharp than the sides of LED corners, but this would obviously be a problem with softer LEDs like XHP50.3HI. I might consider cutting away some corner silicone with a hobby knife beforehand.
But a carefully-shaped 9mm square-opening 5050 gasket does take care of this problem to a large (if not full) extent. If you’re using a non-diffuse TIR and a tiny emitter, you might run into focus issues due to raising the height of TIR, but given that the stock 10deg clear optic already suffers from focus issues (reflecting surface deviating too much from a smooth curve), it’s nothing to worry about.
With an SFT-70 I wouldn’t worry that much about it either (although it still feels kinda wrong) but I want to put the tir in my S21e with an XHP50.3 HI, so I’d like to do it the “proper way”.
I thought about just adding some spacery things between the housing and the MCPCB to lift the tir ever so slightly off of the LED. But when screwing down the bezel, any twisting could still damage the upper silicone layer of the LED since the cutout of the housing doesn’t reach down to the ceramic substrate (I think).
What do you mean by “carefully-shaped”?
Sanding down the ring that normally centers the reflector?
I have the 30° beaded since it looks really pretty and you kinda hyped it up for its nice beam shape and tint blending. 
So I don’t worry as much about proper focusing as I do about light going directions it shouldn’t and thus lowering the transmission efficiency when raising the tir to high.
1 Thank
I see about your concerns with the XHP50.3HI, the soft silicone is easily damaged.
I noticed that the production process for the centering gaskets has changed since my batch (from year ago), the current gaskets are slightly different in shape and worse in just about every way. In response to this, I will offer the following:
- First, try to use the gasket without modifications (aside from possibly carving the bottom to make space for solder blobs to the side of the LED). If the TIR (removed from the white holder) already sits inside the gasket’s circle in a stable way, no more modification is needed.
- Otherwise, grab a hobby knife and gently ream the inside surface of the raised circle/ridge on the gasket. Try to the fit TIR again, and if it doesn’t fit, rinse and repeat until you’ve reamed the inner diameter of the circular ridge large enough to fit the TIR stably.
- On the off chance that reaming reduces the TIR’s height so much that it scrapes the LED again, pad the bottom of the gasket with some sort of hard tape.
When you twist the bezel, all the torque will go into making the TIR rotate against the inner surface of the gasket ridge, which exerts no pressure on the emitter.
Incidentally, this is the same method I used to center a T3 reflector (5mm diameter opening) around a 5050 LED (7mm diagonal).
Very nice! I find this specific optic to be particularly good at fixing emitters that are on the green side, so much so that I would not use it on a pink emitter to avoid making things unbearably pink.
I suspect that transmission efficiency will be lower for XHP50.3 compared to SFT70 due to the much larger LES producing more stray light, but it’s nowhere near as bad as a large domed LED like 519A in a Carclo triple, which probably loses on the order of 30% of collected light.
I’ll probably try the spacer approach since I don’t have these particular gaskets on hand and don’t want to place an order just for them. I’ll let you know how I did it when I did it.
That’s some valuable information still, because I’m planning on fitting an XHP70.3 HI into an S2+ without sanding the reflector (much) to open it up but to instead also try to center it using the inside of the gasket’s circle. I’ll probably open a dedicated thread/topic when the time comes.
Sounds like the perfect fit for my 5000K R9050 then 
As long as I get somewhere around 90% transmission efficiency that’s fine.
Please keep me posted! I’d like to add this alternate solution to my repertoire.
This sounds feasible. Some S2+ reflectors have a conical exterior, while some others (usually smooth reflectors) have a cylindrical exterior that might not play well with this idea. Though in the worst case I suppose you can use a tool to reshape the reflector’s exterior until it fits inside the gasket’s inner circle. The 70.3HI’s emitting surface should be small enough to fit inside the reflector’s opening. I’d be interested in seeing that thread!
This estimate sounds reasonable with this combination. This optic is the right one for the job!
So I made said spacer. Cut out the bottom portion of another TIR housing/holder and sanded it to just under 0.5mm in thickness. Together with the 0.65mm that’s already there, see here, it’s just right for the TIR lens itself not to sit on the LED anymore.
I then superglued the spacer on, so it can transfer any torque from screwing down the bezel to the ceramic substrate of the LED.
So far so good. But as many people already found out, the whole TIR assembly doesn’t really fit into the S21E because it’s too tall. There’s like a 1mm gap between the bezel and the head of the flashlight, maybe a little bit less if cranked down harder. It might work with a thinner glass lens and the o ring between it and the bezel removed but eh.
Another option would be to sand down the bottom of the TIR lens itself and also the top of the white housing/holder so the glass lens sits directly on the optic. But I kinda don’t want to do that either.
Also the small diameter of the optic compared to that of the flashlight looks kinda weird.
Are there any TIRs out there that could fit better?
1 Thank
Very nice mod!
I’ve done this TIR swap and had no issues–the bezel had a less than 0.5mm gap, not nearly enough to compromise waterproofing. It’s hard to crank the bezel tight because of how smooth it is, but I had luck with using duct tape for traction.
Also, I didn’t perform your mod–the metal frame of SFT70 did mush the bottom of the acrylic TIR a bit, but didn’t leave any dust or mess with the beam in any way.
I’ve heard some people advocate for the 23.3mm TIR (same optic in a larger holder), but that should not work as the website indicates they are 13.5mm tall, even taller than the 12.8mm of your optic that is already a bit too tall.
If you are satisfied with fixing the height mismatch, the 20mm 5050 TIRs are just a hair shorter and might do the job. It has about the same diameter as the TIR inside the white holder, and shouldn’t look any weirder. But if you want a TIR whose optical diameter matches the S21E’s bezel inner diameter, I’m out of ideas.
Thanks!
I shaved off the upper edge of the white holder and tried it one more time. Screwing the bezel on felt wrong somehow, as soon as it began to thread in, it was relatively hard to turn. I removed the o ring that seals to the flashlight head beforehand so I could get a better feel of how much torque the TIR receives. I could get it to where there was only a minimal gap under the bezel but at that moment the o ring of the front glass popped out.
Overall it feels scetchy to me installing this TIR, especially with the rather delicate XHP50.3 HI.
The 23.3mm TIR probably works well without the front glass, but I want to keep it in for water resistance.
I had a look at the 20mm ones and given the measurements on the convoy website, they’re pretty much the same hight (distance from MCPCB to front of the optic).
I put in an S2+ reflector for now. It gives me a wider hot spot and less spill, which I like more than the beam the original reflector produces.
Oh I remember this, I ended up wiping all the lubricant from the O-ring to prevent it from moving. Annoyingly, the inside of the bezel is flat and doesn’t have an indentation to retain the O-ring.
Yeah, the softer LEDs like 50.3HI will have their corners damaged by the TIR. Though this should not interfere with the beam/performance.
I believe the official measurement is 0.1mm shorter or something, but in practice it may be functionally shorter because the centering legs can go all the way down to the base of the LED, while for the 21mm TIR, the white holder doesn’t fully go down because the acrylic TIR sits on the LED and can’t go any lower.
That makes me wonder, is there a way to remove the TIR from the white holder (non-destructively), sand the emitter side of the TIR a tiny bit (say 0.3mm), and put it back? This should solve the height problem and prevent damage to the emitter’s corners.
I need help with TIR selection for a S3 with sft42r. I want to have a wide spill without a sharp cutoff, while having a significant hotspot. kind of similar to the M21K or TS11 beam shape. I know a larger head size is needed for this beam but given the size of the S3, which TIR or reflector will be the closest? The main target is to not have a sharp cutoff for the spill.
Ahh that’s an interesting request! If you don’t plan on modding a TIR (the 21mm TIRs with white holder are just a hair too wide to fit), you are down to only the 20mm TIRs in this collection.
Unfortunately, the 15deg flat has little spill (does have a large corona though), and the 20 deg bead is too floody and has a somewhat sharp cutoff (not to mention a slightly hexagonal beam). Other flat optics in this listing make a completely unusable beam riddled with artifacts. But if you find the TS11 to have enough spill, I would give the 15deg flat a try–it’s only 50 cents and the best 20-ish mm flat/clear optic I’ve ever used.
If you are ok with some minor modding, I would consider the 15deg bead optic from this 21mm listing. It has very good throw and usable spill. Use sandpaper to slightly reduce the diameter of the white holder so that it fits inside the S3 head. Note that I do not recommended the narrower 10deg version, there are focus issues and the beam is not as nice and doesn’t appear to throw better to the eye.
4 Thanks
I am down for some modding, any suggestions on what grit of sandpaper will be suitable for this?
The good news is that the grit doesn’t really matter! Since you’re sanding the white holder, which is not optically active, the resulting surface can be rough without messing with the beam. Just whatever grit that is (1) fine enough to not accidentally scratch the TIR inside and (2) rough enough that it doesn’t take forever.
Alternatively, a dremel tool with a sanding head could save you some time.