[MOD] Zebralight SC64c emitter swaps

I just posted a small number of these for sale :slight_smile:

Do we know the tint of these Hi CRI xhp35 Hi? Where do we buy A and D tinted NW XHP35HI emitters?

80 CRI XHP35 HIs are usually Easywhite (MacAdam ellipse step bins). The 45E bins from Arrow look quite neutral; I put that emitter in almost every XHP35 light that comes my way, and I think it’s the one ZL uses for their HI models.

hi, Bob. i was wondering if you could please share a pic of your modified carving wedge or whatever bezel-removal tool you're using now. i'm curious about what it looks like and how wide it is.

i tried with a razor blade, but it's too weak and brittle. i'm considering grinding down a lock pick or a lock tension wrench because of the metal used (spring steel: fairly tough and seemingly not brittle).

i'm trying to get a sc700d open. will post pics if i manage to do it. :)

thanks!

Almost makes you want a J-shaped blade custom-sized to fit the bezel
I’m reminded of the hook-shaped blade on my grandfather’s knife - I was told it was to cut parachute lines easily.

ok, i ground down the handle end of a lockpick stamped from a single sheet (0.5mm spring steel).

my initial impression is the sc700 is probably more annoying to open than sc64. i'm able to slip my tool much deeper under the sc64 bezel, and it's much easier going. i didn't actually try to open up my sc64 since that's not my goal, but i think i could probably do it with the tool i made.

i tried to get the sc700 open, but i don't know if i actually made any progress. i might've lifted the bezel a little, but it's probably my imagination.

i wonder if the sc700 bezel tolerances are different, or if the oring is compressed more. or if the oring sits in a deeper retention channel, and the bezel is basically sitting right on a metal lip. maybe they wanted a positive stop for sc700 assembly.

i guess i could try pressing the glass in a vise or something in case the oring will give a little. will update if i learn anything else.

edit: this is a stubborn SOB. obviously breaking the glass to get into the light is admitting failure. i'm not there yet.

i think what i may do is use a pin vise to drill a small hole into the face of the bezel. that would give me a spot to insert a dental pick or something as a pry tool to lift up and get one spot started. with one spot lifted up a little, maybe then i could work the other tool around like how bob was doing it.

Sorry, I wasn’t subscribed to the thread so I didn’t receive notifications for new replies. Zebralight uses two styles of bezel. The SC64, H600, and SC53 series have the easy to open bezel, but the SC600, SC700, etc. require more effort because the bezel has no lip underneath.

For those lights, the tool need to be thin at the tip, but solid enough you can actually press down on the o-ring and force it under the edge of the bezel. It can also be helpful to gently tap it under, but you have to be careful about the angle and amount of force because it’s easy to break the edge of the lens. Wood carving tool kits with a tool of the style shown in moridin’s thread here are readily available on Amazon, but they typically need further grinding to refine and maintain the shape. You can also try something like a very thinly ground flat screwdriver, but it usually leaves more obvious cosmetic marks like the bezel shown in the photo above.

What LED are you planning to put in the SC700d?

thanks, bob. not an emitter swap but rather a host swap (or mod). zebralight thrower :)

i thought the tool i ground was pretty thin, and i even had a friend press quite hard into the lens next to the tool with the handle-end of a ball-point pen for extra oring compression pressure (the gorilla glass can seemingly take a decent amount of abuse). i'll try grinding a carving tool though. maybe mine was just too weak/flimsy to lift the bezel ring.

I’m curious how well thermal techniques could work. A small butane torch and a can of CO2 duster. Heat the aluminum body, then hit the lens/SS bezel with the cryo blast, maybe enough temperature differential could happen to shrink the ring and have it easily pry out. Maybe even keeping an ice cube on the lens while heating the head could help?

I’d try it myself but my ZL was stolen last year

Thermal stress on glass concerns me.

I figure the odds of damaging the lens with any method is high on these lights.

sorry to keep going a little off topic about sc700, but has anyone actually gotten one open before? or seen a report of someone succeeding with this specific series?

while observing with a microscope, i pressed as hard as i could near the bezel ring using a plastic rod but didn't see the lens/oring giving at all. doesn't necessarily mean anything, but it makes me wonder if the usual method doesn't work on this. i'm leaning towards trying to make a small hole in the bezel ring as a spot to start prying.

Haha, thanks - I was on mobile when I asked, so I wasn’t able to find and link this thread.

i just bought a new sc64c le to put a 519A 3500K dedome. first time taking one apart.

i ground down the handle of some metal spudger tool i had on my bench. you could probably make a tool out of almost any suitable piece of steel. just needs to be rigid enough to not flex in use. i worked it on an extra coarse whetstone and put a convex grind on it. the edge needs to be thin enough that you can fully insert the tool under the bezel. the edge radius should also roughly match the bezel radius so you get a decent contact area.

the red line in the image below shows how i flattened the edge profile on the right side (increased the profile radius). you can see the original radius to the left of it which was too narrow and didn't make enough contact.

after dialing in the blade geometry, the bezel came off very easily.

choil shot of the blade:

here's the driver removed. i added some test leads to test the circuit ex situ. spoiler: i didn't break it :)

i think it's interesting that the potting all came out with the pcb. i haven't seen a pic of this online before, so idk how common that is.

album link: https://imgur.com/a/XAKnZ2G

questions...

what are you replacing the TIM with? i have some Noctua NT-H2 paste, but i'm not sure if i want to use it because i don't think it's designed for long term application. i think performance degrades after a few years, and it's meant to be re-applied. depending on how i reflow, maybe i can just re-use the existing paste (but probably not).

how are you guys reflowing? my IR preheater is in storage, so i probably won't pull it out just for this. also, the potting is kind of in the way on the bottom. maybe i'll just do classic hot air from above (maybe with some gentle preheating with a chem lab style hotplate, but those are a little hard to get dialed in). or maybe i'll try pressing a flat style iron tip onto the brass block from below, but i don't have a good board vise rn.

Take a large tip for your iron and apply it to the copper block from below. This works much better than hot air.

all's well that ends well. if i ever have to do another one of these for some reason, i'm sure it will go much faster and smoother. but it wasn't bad honestly.

i used a knipex pliers-wrench with a rubberband as a board clamp because i have nothing else available:

i wasn't getting fast enough heat transfer with a dry (but tinned ofc) iron tip (used a 45° flat chisel type for good contact area). i didn't want to use solder because i wanted to leave the nice gold plating alone, and i wanted it to stay as flat as possible.

instead, i used hot air on the block from below. i left the potting on the underside of the board intact and used it as thermal insulation. aimed the air away from the switch and towards the potted components. worked fine, but i didn't perfectly center the emitter. only noticed after reassembling and seeing that it wasn't perfectly centered in the reflector. oh well. not worth it to redo it.

i dedomed the 519A sm353 (3500K) with a double edge safety razor blade. just did it freehand after reflowing. i gently sliced it off in about 3 slices. i did slice cutting instead of push cutting. tried to minimize stress on the emitter package while doing so, particularly normal stress. tried to make it mostly shear stress. i got the emitter from @azhu btw if anyone's looking for some.

i used noctua nt-h2 paste because i was impatient and didn't want to wait for shipping, but arctic mx-4 or Innovation Cooling Diamond might be be better choices (might last longer without drying out).

i removed the solder on the VCC pad and GND pads (by the screws). i diluted it with some eutectic Pb-Sn to lower the melting point and make cleanup easier, and then i pulled it with wick. then i added fresh Pb-Sn. this made it a little easier to re-solder the supply (especially the screws) at the very end.

new emitter installed and dedomed:

before reassembly, i chamfered the edges of the potting so it would slip into the milled recess more easily since it has to rotate into place.

i used a parallel clamp to press the bezel. worked well and gave me decent control:

beam shot:

left to right:

  • sc64w hi (high cri 4000K 90+ XHP35 HI, bob)
  • sc64c le (Nichia 219B R9080 sw35 3500K, bob)
  • sc64c le (Nichia 519A R9080 sm353 3500K M400 L5 dedomed, me)
  • d4v2 (Nichia 519A R9080 sm353 3500K dedomed, stock from hank)

Good job!

Looks fantastic!