sk68 clone: longitudinal section

For future reference, sectioning like this goes a lot better, and easier if you pot the entire part and draw a vacuum to remove the air bubbles. Once you remove half, you can polish up the face to get a nice outline with everything frozen in place. If you remember to cast it in a nice “frame” or have a way to square it up and polish the outsides, it makes for a good showpiece.

very nice work, though. Definitely an out-of the box review!

edit… Just found some money in my DX account and have one on the way :party:

I can’t believe I have no AA/14500 lights!

Beam shots or it didn’t happen!!! J)

I enjoyed that.

Do a Fenix TK75 next! lol :zipper_mouth_face:

Reminds me of the half cup of tea in Disney’s Alice in Wonderland.
I can’t find a good image of it.

LOL. Beam shot! Too funny.

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:

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

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

@warhawk: great beamshot! :-D

Will It Blend?

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 :-)

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 5x7135 driver or to go direct drive.
This design will be mature when it becomes easier to control multiple amps. within 15 mm.

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

@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.

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)

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.

So the lens is just pressed into the bezel?

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.

What about the structure? How does the length of the pill affect the strength?

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