I just used a chunk of 1/4" aluminum stock I had got off ebay a while back. I used a hacksaw to cut it into a rough circle shape. Then I used a belt sander to refine the shape. Finally, I used needle files to make the four notches for the wires and screws.
I just bought a new piece of 5mm thick 25mm x 100mm aluminum from AliExpress. It was like $3.50 with shipping and tax. Cheaper than I could have got a piece from ebay.
I donāt think Iāve sliced a 70.3 but I have sliced a 70.2, maybe 6000K (came with Thrunite T2), and it turned out great. My impression is slicing should work with 70.3 but maybe not.
It definitely should work with the 70.3 also. Iāve seen where others have done theirs and got good results.
It sucks that I essentially turned a good emitter into basically trash, but I can live with that. It sucks more not knowing what I did wrong. I used a 1mm thick washer, and ended up with what I thought was a decent nearly flat surface.
Thatās interesting, I definitely didnāt get it totally flat. There is a bit of unevenness, but I didnāt think it would make such a big difference. I can try to smooth it out but I donāt have much silicone left to work with.
That at least gives me some idea of what happened.
I only sliced the dome off. Using the 1mm thick washer as a guide to run the razor across, but was finding it difficult get it perfectly flat.
Iād be too nervous to try that dicing. I did follow a few links in that thread though. One I came across mentioned polishing the dome with some fine sandpaper. At this point I canāt make it any worse, so I think Iāll give that a try.
edit: Well I polished up the slice marks, but the duv didnāt improve any. Iāve attached a couple pics after polishing. At this point Iāll attempt to ādiceā it too, not expecting any improvement but just to try it out.
I donāt know whatās up with the solder mask on the mcpcb, it started coming off right next to the led while cleaning after reflow, and itās only gotten worse.
That makes sense if you have one in a flashlight you like, but Haukkeli apparently sliced 20-30 of them. That seems to be somewhat on purpose. Is there any (relevant) advantage of a sliced 70.3 HD over a 70.3 HI?
I as far as I was knew slicing is supposed to lower the CCT and duv. Iāve seen many times people have done it successfully, but apparently I did something wrong.
Mostly Iāve been building different lights and have been spending some money trying to find good bins. Usually buying 2-3 from different sources hoping the best.
I re-modified my C8 that I built around 10 years ago. It had an XP-L HI and was a great thrower, but I rarely used it.
I read way above (from ebastler) that the high CRI 5700K 70.3 HI from Simon has good tint, so I debated whether to just buy a new 70.3 HI C8 or buy the parts separately. The new C8 was only $2 more vs the parts, but Iām going to use the existing driver for another flashlight so I guess that saved me another $11.
A very simple build. I just had to pick off a solder blob next to the LED and lap the MCPCB. Iām always surprised that the LED boards are not more flat. Here it is when I just started to lap it, and then at the end.
Iām really impressed with the 70.3 HI! The beam is very nice with the OP reflector and makes my C8 much more usable. And I agree with what @ebastler said, itās a great tint-free and tint-shift-free cold high CRI 70.3 HI emitter.
I can always find something around the house thatāll work. But whenever I throw away electronics or appliances I always take out the stuff I think I might find a use for later. Lots of copper lying around. I have a few extra chunks of copper pipe from idk where, some plumbing project or some cooling coils, Iāll squeeze those into a flat chunk in a vise or hammer them down so itās just a chunk of copper, then cut and grind that to size.
I always have a handful of damaged mcpcbās lying around too, where the solder mask came off or whatever. Can polish those off and use a few of those. Or if I find an old penny. Canadian pennies were 98% copper until 1996.
It is an issue isnāt it. They should really fix that. I always forget how bad it is until I hold a noctigon or kaidomain board.
Iāve never sliced a 70.3 HD, but I have sliced several 50.3 HDās and I prefer them to the 50.3 Hiās. It lowered the duv on all of mine. I like the tint better.
I never really used my SFT-40 M21A either. It was also an impressive thrower, but I always found myself using my M21B instead. Initially I was going to get the OP 10mm holed reflector, but Iām a sucker for a TIR.
Same here, I always save any chunks of copper and aluminum. I also have a bunch of CPU and other heatsinks Iāve scavenged from obsolete motherboards.
For the Americans, US pennies up until 1982 were 95% copper.
I must really not know what Iām doing when it comes to slicing XHP emitters. Several months back I had also tried my hand at slicing a 4500K 90cri XHP50.3 HD. Unfortunately, the duv didnāt decrease, but it didnāt increase like my XHP70 did. I probably shouldāve learned from that experience and not tried slicing again.
Idk what Iām doing right lol. My slices are not perfectly smooth. I donāt use a guide most of the time, just freehand. And it usually takes a couple slices. But itās always worked.
I always use a brand new utility knife blade for every emitter. Sometimes 2 new ones if it takes a few slices to get right. Maybe thatās it? The replacement blades for my Milwaukee fastbacks I buy in packs of 100 so I can always slide out a brand new one, never used, still oiled from the factory, sharp as can be for each slice. Thatās the only thing I can think of that might be making a difference but idk
I really like the sft70 in the m21b. I wasnāt a fan of the sft40 in it, I like the sft40 in the m21a, but the sft70 needs an OP reflector so you canāt get a ton of throw from it anyways, and itās more lumens than the 40, so it works great in the m21b
I used a brand new Feather double edged razor blade. Iāve been saving a pack of them for when I get the ambition to wet shave again. So, it most likely wasnāt the blade causing my issues.
I sanded a bit more off the XHP70 and it appears to have lowered the duv a bit, but I still need to check it with the Opple.