XHP70.2 dedoming pictures and VIDEO added

Nice job!

Zozzv6, have you been able to run high current through yours? I sliced and diced one similar to your, cleaned it properly with surgical spirits, and put it back into my BLF GT70. It works perfectly with ramping, but on Turbo it starts burning. I immediately switch off the light and clean the black spot with surgical spirits, as the black is really on the leftover dome. It then again works on any mode less than Turbo, but what’s the point of a BLF GT70 that can’t use Turbo :smiley:

I’m guessing I sliced it too close to the die. What’s my options? Slice deeper still? Completely remove the dome, has this been done?

I run turbo in my MF02S with no problem. It is fet driven so almost same as in a GT. You need to make sure nothing dirt left on silicone. It is hard to get it off completely because phosphor has rough surface and the dome material bonded in thet surface. So you always have some leftower or cut spme phosphor too which can cause blue tint shift.

So do you recon my burning is either because of leftover residue or a rough/crumbly surface as apposed to the layer being too thin? Should I then try cutting closer in an attempt to get a flat and smooth cut?

Try to cut down the burned part and blow led with compressed air. Not your cut rough. The die surface rough and dome material diffunded in that when the led was manufactured.

Great info. I would like to duplicate your spacer. Never tried it and this would seem to be a good start. If you want to tweak the aluminum plate would you go thinner or thicker? Cree specs for the XHP70.2 (page 26) as 0.56mm for the base. Online metals has small sheets of (0.81mm / 0.032”) Too thin? Also, 1.016mm / 0.04” sheet Thanks for any help.

Go for the 1,016mm. Mine is 1mm and if the razorblade bending a little it is easy to cut in the dies. The base thickness is without the dies so they add a little and also you need to keep a thin layer silicone on dies. So 1mm is fine.

Thanks for the quick reply and recommendation. I have some single edge Schick injector blades that are thicker and stiffer that I’ll try.

Slicing is not a big deal but the edge cleaning from phosphor is a harder job. So I made a video to see better how I do the second part. Maybe tomorrow I have time to edit and upload it.

Today I achieved a very clean cut with a new razor:

You can see the dies good on this one:

This is the thickness I start dicing:

Here you can see the end result and the silicone left on the dies and on dies side. And the rough border between dies and silicone. That is why you need to leave a little silicone.

4,9V
1mA

Thanks for all info. Great pictures. Another interest of mine that has practical applications is wet shaving. And Feather Hi-Stainless Double Edge Razor Blades are widely regarded as the sharpest (see picture from my photo stacking days). Not sure that helps if that is the easy part, but I wonder if some chisel scalpel blades might be useful. SM61 or SM62 Swann Morton Expensive and hard to get though. Looking forward to updates.

I was looking for a chisel grind when I bought my scalpel and blades, purely for slicing domes. Did’nt find those and have had to learn to hold the bevel parallel to the die face. I also apply silicone to the blade so it drags less, and still I do a slice rather than push cut.

Silicone grease? Doesn’t some of it stay on a dome?

I learned the hard way (read: mucked up my BLF GT70 XHP70.2) that a push cut can cause the dome to rip off at the end of the cut. :frowning:
Also, would it be better to do multiple cuts, each time going lower in an attempt for the piece of dome being cut off to have more flexibility and glide up against the top bevel and not cause a rip or tear infront of the blade?
Then last question: Would the left-over dome on top of the dies burn if they are too thin? Or would they only burn if there is residue on them? In other words, would a perfectly smooth and clean cut 0,001” above the dies start burning, or would it function correctly?

I contacted a seller in the UK, about the dimensions, of the SM 61 and SM 62. They come in a single bevel design SM 61 SB as well, which would be more useful. I’m assuming they mean like a wood chisel and not facets to the cutting surface. Might be to thin for the initial cut but possibly be used, with a thinner spacer, to chisel around the diced die?? I got get one of these and take the plunge. I hope you could put a video together. I’m apprehensive about making $20 mistakes.

Video is almost done

And the video is done. It is 8 times faster than real life and the same things on opposite sides only appear once to not be soo long and boring. In reality it takes 20-30 minutes. I add it also to the OP.
Enjoy it:

Thanks Zozz. A video is worth a thousand pictures. I have one to do so hope I dont stuff it up.

Very nice work, Zozz. :beer:

Thank you all!

More meticulous than actually hard, just go at it slow and easy. Being especially careful at the dice portion to not clip the edge of the die… this will result in a visible blue emission if phosphor is chipped off the die surface. :wink: