sk68 clone: longitudinal section

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WarHawk-AVG
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Ricflair wrote:
Beam shots or it didn’t happen!!!!!! J)

I enjoyed that.

Do a Fenix TK75 next! lol Oops

Wilson
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LOL. Beam shot! Too funny.

Inquire…Choose…Proceed

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Nice beamshot LOL

I don’t know why I find this flashlight splitting so amusing. I guess maybe, maybe, this defines the time where we cross from enthusiasts to nuts category. :bigsmile:

musicmagic
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Fritz t. Cat wrote:
The problem with screw thread fit is apparently thermal expansion from the heat generated while machining. Of course more expensive lights can be made with the lath turning more slowly and maybe cooling liquid and better compensation for the expansion.
Cheaper lights, on the other hand, because they may sell in much larger quantities, can have more work and talent going into programming the numerical control, so they can have nicer shapes than more expensive lights can.

Not sure I agree with all that, but then again, I know squat about machining.

If you can’t blind them with your brilliance, baffle them with your bullcrap.

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Pulsar13 wrote:
Nice beamshot LOL... I don't know why I find this flashlight splitting so amusing. I guess maybe, maybe, this defines the time where we cross from enthusiasts to nuts categowry. :bigsmile:
 

:bigsmile: and meanwhile practise the fine art of destroying.

@warhawk: great beamshot! Big Smile

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Thanks djozz, very interesting and informative.

Bet that was not an easy task!

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DBCstm wrote:
Thanks djozz, very interesting and informative. Bet that was not an easy task!

The sawblade blocked numerous times, and three quarters underway it did not like hitting the tail spring and some teeth broke off, but it was old anyway, the new blade was doing much better Smile

Fritz t. Cat
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Love the beam shot.
I had heard that the body is too thin where it conducts heat from the pill to the finned section, and the picture shows that. The wide part of the pill hits the end of the body before the bottom of the pill touches the small ID of the battery tube. It looks as though this example is not exactly following the original concept of the design. There is no reason for it to be so thin there. The end of the battery tube appears to be cut away to make space for a longer pill below the driver. Either the outside edge of the pill should extend farther back or the ID of the battery tube should remain small to the point where it reaches the pill we see. It would be better for the pill to be longer, because that gives more contact area between the pill and body. I can’t say whether any were actually made that way. Some have solid pills, so maybe some have longer pills.
In a mod., the lengths could be shifted so the pill screws down farther, or else one could add a copper or aluminum ring to fill the empty space. In mine, I have a 17 mm. driver there, which is convenient but doesn’t help the heat flow. It provides an incentive to learn to build a BLF SK68 5×7135 driver or to go direct drive.
This design will be mature when it becomes easier to control multiple amps. within 15 mm.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

WarHawk-AVG
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It seems the SK68 5*7135 that Cereal_killer make are quite popular…says he can’t keep em in stock Wink

Glad people are enjoying that build

djozz
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@Fritz: every sk68 I have seen has this thin piece with the driver not touching the thick part of the battery tube. It just is a bad design (too thick walls where it is not needed, too thin where it matters), and also  I don't think the sk68 is particularly goodlooking. The reason of its popularity is that it is very cheap, despite the design it just works, and the optical lay-out is very decent. And no-one bothered to make a better cheapy zoomie with the same lens.

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very nice, if you put on anew LED and move all the circuitry to the remaining half you could have a functional light Wink

perhaps you should do a giveaway with the condition that the winner does this (and if a way can be found to use half an LED)

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I like the SK-58 better, except when the extra mass and area are needed for cooling.
I still think the pill touched at the bottom, at least in the mind of the original designer, because otherwise why cut the large diameter threaded hole so far down? If we can’t find them like that, we can still put something to fill the hole.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

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So the lens is just pressed into the bezel?

Fritz t. Cat
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I don’t see anything but pressure to hold it in.
The SK-58 has a similar space under the pill. Perhaps the thin section is to keep the body from feeling as hot. I am imagining a management decision based on beta testers complaining about it feeling hot. That doesn’t invalidate the fins on the 68, because they do keep it from feeling as hot.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

Fritz t. Cat
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What about the structure? How does the length of the pill affect the strength?

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

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Nice job on the cut! Smile Anyone willing to volunteer a nice FourSevens XM18 to djozz to saw in half ?

That Canadian flashlight guy & Lantern Guru -Den / DBSARlight

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Love the effort that’s gone into this review!
Well done, we should now refer to this light as the Sipik SK34

djozz
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Fritz t. Cat wrote:
I don't see anything but pressure to hold it in. The SK-58 has a similar space under the pill. Perhaps the thin section is to keep the body from feeling as hot. I am imagining a management decision based on beta testers complaining about it feeling hot. That doesn't invalidate the fins on the 68, because they do keep it from feeling as hot.

You wrongly assume that expertise and finetuning has played a significant role in this design. There once was the Nitecore Extreme Infinity:

(BTW, it is a reflector based light, not a zoomie). And someday a chinese factory made a zoomie stealing the design, I assume that that first clone was the Sipik sk68. It was done fast and cheap without much thought, but it appeared to work well and eventually it started selling quite well. And that last thing, and only that last thing, is what triggered the chinese industry, and the response was not let's make it even better, no, it is: let's copy that. And later: how can we make an exact as possible copy even cheaper.

If the first designer had bored out the pill cavity a bit less deep so that the pill touched the battery tube on the underside, the heatsinking would have been great, and that great heatsinking would have appeared in each clone. But he didn't, and the light worked and sold well...

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Here is your review…ok? Thnks. Bye

Big Smile

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http://budgetlightforum.com/node/24847
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DINODIRECTSCAM COMPANY. DO NOT BUY
http://budgetlightforum.com/node/11324?page=2#comment-254983

Fritz t. Cat
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djozz wrote:

Fritz t. Cat wrote:
I don’t see anything but pressure to hold it in. The SK-58 has a similar space under the pill. Perhaps the thin section is to keep the body from feeling as hot. I am imagining a management decision based on beta testers complaining about it feeling hot. That doesn’t invalidate the fins on the 68, because they do keep it from feeling as hot.

You wrongly assume that expertise and finetuning has played a significant role in this design. There once was the Nitecore Extreme Infinity:

(BTW, it is a reflector based light, not a zoomie). And someday a chinese factory made a zoomie stealing the design, I assume that that first clone was the Sipik sk68. It was done fast and cheap without much thought, but it appeared to work well and eventually it started selling quite well. And that last thing, and only that last thing, is what triggered the chinese industry, and the response was not let’s make it even better, no, it is: let’s copy that. And later: how can we make an exact as possible copy even cheaper.

If the first designer had bored out the pill cavity a bit less deep so that the pill touched the battery tube on the underside, the heatsinking would have been great, and that great heatsinking would have appeared in each clone. But he didn’t, and the light worked and sold well…

I know all that, but don’t believe that a designer adapting a reflector light shape to a zoomy would miss a small change that would improve both the heat flow and the mechanical strength.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

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Honestly, I don’t think the designer really cares. Its cheap, lights up and doesn’t burn out within the 45 day paypal dispute window, its perfect! Next.

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Looking in Alibaba, the first listing I find for an SK-68 says “Supply Ability: 50000 Piece/Pieces per Month”. I don’t suppose the designer expected that much success but I think he must have taken the project seriously, probably more seriously than the one who designed the obscure Nitecore Extreme took that design. He relied on Nitecore for style, but did his own engineering. And he got the most important part right, at least, the production cost.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。

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Lol what an review, very original idea. Cool beamshots too Silly

some of my actual experiments and reviews:
UF-T20 review and mod —->http://budgetlightforum.com/node/30186#node-30186
My EBRZM, over 1 million cd thrower—-> http://budgetlightforum.com/node/30274#node-30274
Ervin’s try (2nd. Annual BLF Scratch Made L

Explicit
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This is the most informative review I’ve read on flashlights. Congrats and thanks.
Now, I’d love to see a more high end flashlight reviewed in the same way, but that would be too much to ask. Smile

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Explicit wrote:
This is the most informative review I’ve read on flashlights. Congrats and thanks.
Now, I’d love to see a more high end flashlight reviewed in the same way, but that would be too much to ask. Smile

if you pay for the flashlight i bet someone would be willing to do it for you

The Journal of Alternative Facts TM

"It is critical that there is a credible academic source for the growing and important discipline of alternative facts. This field of study will just keep winning, and we knew that all the best people would want to be on board. There is a real risk in the world today that people might be getting their information about science from actual scientists"

 

djozz
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Explicit wrote:
This is the most informative review I've read on flashlights. Congrats and thanks. Now, I'd love to see a more high end flashlight reviewed in the same way, but that would be too much to ask. :)

Thanks Explicit, I may split a high end light some day but perhaps cheapy's are the more fun because the design flaws are obvious.

Welcome to BLF! Smile

Explicit
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Bort wrote:
Explicit wrote:
This is the most informative review I’ve read on flashlights. Congrats and thanks. Now, I’d love to see a more high end flashlight reviewed in the same way, but that would be too much to ask. Smile
if you pay for the flashlight i bet someone would be willing to do it for you

I’d certainly not be willing to pay 100% by myself, but I’d gladly participate in a crowdfunding project. I’d be willing to participate with, lets say 0.05 Bitcoin (roughly $25). If this “review” project is backed by 20 people the funding would total to 1 Bitcoin. I think this would suffice to “review” a $100 flashlight. Anyone else interested to participate?

Explicit
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Thanks djozz, I am glad you noticed that it was my first post.

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musicmagic wrote:
now cut a battery in half to complete the picture. Evil

Hahaha yeah!

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