Got mine on Fri. Thanks MTN, that was 2 days shipping to FL, :sunglasses:
While I like the new matte color and 90cri screwed in star/emitter, not so much liking the ruff surface finish.
Seems like a much less quality finish, even though Iām sure it isnāt.
The threads are ruff and course when screwing the tailcap on, or the tube in, or bezel on. Threads, are even ruff/noisy with gobs of lube. This is on both my new matte green and matte blue D4 lights.
Might be from the ruff āfluffyā porous surface finish that might be a .001-.002ā āthickerā ā¦?
While Iām sure the ruff porous feeling surface might increase grip, not sure I need that. The old finish grey, green and black I have, donāt seem to be slippery at all to meā¦? When a little lube or grease/dirt get on the new matte finish, it stands out and doesnāt just wipe right off like the smooth old anodizing. IMO, the old finish seems to reek of quality and perfection. The old green/grey is a superb job of anodizing and hard to beat imoā¦
Donāt get me wrong, I like the new matte finish, its ok, and would buy them again, just donāt think the surface finish feels/matches the quality of the old anodizing.
Now Iām sure many here will disagree with me, thats ok.
That blue one looks really nice. Given the choice of a matte blue or matte green, Iād go with the blue. I do like the older smooth green thoughā¦ and I still want purple.
My D1S has the matte finish too, and Iāve felt the need to be extra-careful with it because of past experience with bead-blasted titanium. It seems to hold up better than the titanium finish, but it still seems like itāll be a lot easier to scratch than a smooth anodized surface. Things also tend to stick to it, so there are a lot of materials which leave a mark (sort of like using chalk on a chalkboard). So I often have to brush marks off it.
Does anyone have a link to some GITD and regular lens o-rings for the D4 that will work to take up the extra space after swapping to Mtnās offset MCPCB? Also, any idea if anyone will offer the 4000K Nichia 219C 90+ CRI version that Vinh had again now that he is sold out. Thanks.
The difference in MCPCB thickness is only about 0.4 mm, IIRC. Hank tells me itās important not to change it because that difference matters, while RMM tells me itās close enough that it doesnāt matterā¦ So I swapped the MCPCB on one of mine and it seems to work fine. I did some thermal regulation tests on it and it didnāt have any issues related to that. Just make sure that the bezel is really tight so itāll apply enough pressure. It may also help to put the O-ring above the lens instead of between the optic and lens. This likely improves waterproofing and helps fill the 0.4 mm gap, but you should make sure to check it afterward in case the O-ring tries to pop out while tightening the bezel.
You donāt think it would be worth it to put an o-ring above and below the lens to help take up the space as long as the bezel wasnāt tightened too tight? I am thinking about building a Goldilocks mod D4 with Mtnās offset MCPCB, Nichia 219B SW40 D200 L2 R9080, GITD lens o-rings, and a Carclo 10621 optic. If I canāt find a factory 219C 4000K 90+CRI that is.
After cleaning the threads on my blue D4 3 times itās about as smooth as the old green D4. The anodizing rubbing off does turn the lubricant and threads black. I was concerned the o ring was melting but it isnāt.
You would just have to cut out a 20mm disc, drill some holes, and make sure to use thermal paste on both sides. It would be pretty easy to make a spacer. A 3/4ā holesaw should be close enough as 20mm=0.78ā or it might even be possible to cut it with a blade knife as its only 0.4mm thick. Someone with access to a machine shop could make a bunch and sell them as well.
The termal paste has worse heat resistance than copper So I would not do multiple paste levels and spacer sheets even if it is copper. But that is just my opinion.
You only need one level as this sheet is exactly 0.4mm(the needed thickness to match the OEM MCPCB). And, Arctic Silver 5(for instance) is almost 90% pure silver. Silver has a better thermal conductivity then copper so, I doubt it makes much of a difference if it is applied right.
Also, Vinh from Skylumen has done this many times to add thermal mass on high output lights and it seems to work just fine.
For adding thermal mass under the led shelf or elsewhere is OK but for making sandwich between MCPCB and led shelf I think not. If the only way to get it right is a spacer under the MCPCB I rather solder the spacer to the bottom of the MCPCB. Soldering with good paste has around 220 W/(m*K) thermal conductivity.
There are thermal compounds with 70+ W/mk and like I said other modders have done it and it works just fine. We are only talking about one extra layer of thermal compound and it will be extremely thin due to the MCPCB being screwed down on the D4.
I was just suggesting this as a solution to Hank saying using a thinner MCPCB is not a good idea. If just taking up the extra space between the lens and optics to ensure water tightness, an o-ring would work fine.
Really, I donāt understand why Hank didn`t use an offset MCPCB design in the first place when it gives a better beam shape(round like it should be).
I forget where the thread is, but someone around here did some actual testing on which factors affect thermal performance the most. What they found was that the most effective ways to improve the heat path are to reduce the number of interfaces, and to increase the amount of pressure on each interface. Type of thermal paste (including none) was a relatively small factor.
What this means is that adding a 0.4mm spacer between the MCPCB and pill is probably one of the worst options, since it adds an interface, and it would be far more effective to simply ensure that the MCPCB has lots of pressure against the pill.
Donāt add a thermal interface if thereās a way to avoid it.
Two green SMD LEDās powered directly from the driver with a feed & neutral and 22K resistor.
After a few failed attempts to use wire for the connections I ended up using copper tape instead.
I filed two cutouts either side of the switch for the wires to come up and soldered onto the tape.
These switch dimples are very delicate and will come off fairly easily.
Covered over with some diffusing foam, put steel retainer back in and siliconed in place.
