ITS HERE! SIPIK SK98 - A 18650 based Sipik SK68 with an XML!

Any ideas on how to improve heat sinking? Thermal compound perhaps?


What you see there is a 18x6mm solid coper disc.

That should do it UPz :slight_smile:

My thoughts exactly. Fabricate that disc yourself? Or available for purchase somewhere?

Might just as well dump the star and mount it straight on copper. You know... since it's right there...

No, UPz just likes tempting people with home made things and then saying they aren't for sale. :P

:bigsmile: Cool! I might as well do that.

I see how you still remember that lathe-born mag heatsink :open_mouth:

The copper disk is pretty easy to machine, no electric tools needed. The most important part is to find a correct diammetter stock bar of copper. The hole in the pill measures 18mm (17.8mm in another unit, some tolerance). Go to your hardware store and ask for a copper bar of 18mm, cut a disk using a handsaw of 6mm.

Cut to small bits on oposite sides for the wires.
Try to fit the disk in place, use sandpaper if needed. The hardest fit the better.
I’ve used a vice to push it to the place.

More pics here.

PS: Sorry for my terrible engrish english

I never see any copper bar where I live. Especially not 18mm ones. What are they for anyway? (real usage)

Lathe works.

I have multiple diammeters at work, but here can be found on hardware stores.

I read this post and the reviews and negative first impressions, and then ordered an SK98 anyway for the heck of it. I really dig my little SK68 and even the UF 3-mode clone I just got. I figure if this SK98 has high and low modes, and I’m not abusing my torch with rigorous testing and running on high all the time, maybe I’ll at least get better, larger-format performance than the SK68 even with the SK98 on low. Obviously zooming an XM-L emitter isn’t going to be the prettiest throw, but having a powerful LED zoomy in my collection seemed like a good idea if not for just the fun factor alone. In fact, I have another eBay no-name special (not a Sipik clone - different design) on the way that boasts 1400 lm. LOL. But I’ll bet that actual 300 or so lms will seem pretty bright when zoomed to throw. Some guys report the SK68 only topping out at 90lm or so, but the perceived brightness of the little rocket seems to be so much more because of the zoom function. Gimmick or not, it’s fun to have a 100 yard beam capability in a little device that fits in my front pocket.

Any feedback on my ideology? If we don’t run this SK98 on high for any length of time, can we expect it to hold together? Anyone else order one of those other 18650 zoomy things from eBay or elsewhere?

I really like my Poppas W-878! Very versatile battery configuration (26650, 18650, 3AAA) and very large flood. $16.33 at Manafont.

-Garry

Ooh, nice! Yeah I saw those, and your review. Hmmmm….

any reviews ?

I can give a simple layman review without draw measurements and photos. I just got my SK98 today, and because I have a couple loser UF red 18650s that have bunk protection circuits that don’t allow enough draw, I’ve not been able to play much with it. But I have a third red 18650 that seems to hold at a bit higher draw, and the driver in this SK98 wants to pull more voltage, which I guess is a good thing. If you read the reviews earlier in the thread that the plastic portion of the “pill” might melt within several minutes on “high” because of poorly designed heat-sinking(or lack thereof), well that may be the downfall of these lights.

That being said, mine is REALLY bright. If you own an SK68 or one of the clones, you know how they can perform and they are impressive for the size. So it’s somewhat exciting to know what a 18650 version might be capable of. I was. I don’t plan on using mine on high for any length of time, so I appreciate the mode options.

Anyway, I’ll cut to the chase - and make it simple: everything about the SK98 is BIGGER. The size, the flood, the amount of light out the front, and somewhat sadly, the size of the projected emitter zoomed out to throw. It’s huge, not a pin-point of fire like the SK68, which is shooting out far less lumens, but seems so bright because of that small diameter throw beam. The SK98 seems not to throw as far because of such a large throw spot.

But, it is bright. If you read in the thread above, there are some cool suggestions to mod the pill for sufficient heat sinking to prevent meltdown on high. The potential for cool mods to improve this light is pretty good if you mod, but not much will change the fact that you cant zoom-throw the big XM-L emitter like other LEDs.

The more experienced members here can critique my assessments freely, because I’m just learning this stuff. But I think I get it…

And welcome to the BLF. I hope you have fun here. In fact it already seems like you do.
And I do appreciate the “laymans review”. In fact it made me think I still need this light. I guess I´m easy & cheap :wink:

I’m working on a review. I’ll try to translate it to english and post it in BLF if I find time.

I’m a newbee here, so I may not know all the voltages and correct terminology, but I have two Ultrafires that look like the Sipik and one Sipik (that coincidentally just came 20 minutes ago from Manafont). The Ultrafires (from 2 different ebay sellers; no model number on light) are slightly (15%?) less bright but do not have the rapid overheating problem the Sipik has. Yes, I tried several different batteries. They DEFINITELY get hottish warm, but not like the Sipik.

I noticed the heat on the Sipik almost the minute I turned it on. You can feel the heat start building in literally 30 seconds, on mine anyway. The Ultrafire isn’t like that. I haven’t done a side by side heat comparison, but it’s a substantial difference I think. At first I was psyched that the Sipik was marginally brighter than the Ultrafire, but now I’m pleased to have the Ultrafires as they seem more usable, although a little less bright — but still bright, marginally the brightest cheapy (under $18) T6s that I have.

Obviously I like the light. I bought three of em!

Thanks Ledsmoke! Happey to be here. :slight_smile:

Ubehebe, I agree. My UltraFire clone is not nearly as bright as my real Sipik. And it has the 3 modes. I still love the Sipiks so much though… :slight_smile:

The Sipik also has the same semi-defect with the clip arm as the Ultrafire, so it’s probably best not to put too much pressure on it. There is a big honking hole in the clip up near where it attaches to the light. That should be the clip’s strongest point, but it appears to be the weakest. I read somewhere else that the clip has a tendency to snap off at that weak point, exacerbated by the fact that the clip steel may not be spring steel. Mine hasn’t broken yet, but I see how that could be an issue. I have a broken light with a similar clip (without the hole), so I may switch at least one clip.

FYI: The clip on my sipiks have only broken when being “mangled” with tools like a adjustable wrench. YMMV.