Home-Built Nitecore SR3 18650 tube

[ASheep]

G'day guys, I thought I'd document my first light "mod" here. I recently purchased a second hand Nitecore SR3 (cheers tolkaze). I love the light, but at full power it'll suck a CR123 dry faster than you can blink (well, 45 minutes). RCR123's fare even worse, giving about 30 minutes runtime... Seeing as it is basically impossible to find one of the 100 nitecore 18650 tubes, I decided to build my own.
I found a piece of stainless steel barstock I had lying around from an old project, measured up the threads and worked out the length of my new tube, and started machining.
Here are two (blurry) photos of my work so far, I had to stop to pick up my girlfriend. I'll finish it tomorrow morning and update this post with nicer pics of the finished product.

Sorry for the terrible quality photos, all I had on me was my camera phone, Tomorrow's photos will be much better quality, I promise!

In case anyone was wondering, the head and tailcap threads are different pitch and diameter... I'll list the specs here, cos I saw a thread the other day with someone wanting to know them.

Head thread:
Outside Diameter: 22.2mm
Pitch: 1.25mm (V cut)
Length: 4.8mm

O-ring groove (head and tailcap):
Diameter: 20.3mm
Width: 1.6mm

Tailcap thread:
Outside diameter: 22mm
length: 5mm
Pitch: 1mm (square cut teeth)

External Dimensions:
Overall Length: 69mm
External knurled diameter: 23mm

Sorry about the longish post, but I needed to show someone my work, as my girlfriend just rolled her eyes...

 

[lyyyghtmaster]

Sorry your girlfriend doesn't quite appreciate the superb nature of what you have done! :shakehead Thank you for posting this! If all else fails I may be needing it!

As an aside, how come you chose SS instead of aluminum for this? Was it just a matter of what you had on hand?

 

[ASheep]

Thanks for the compliments lyyyghtmaster, my girlfriend is pretty supportive of my obsessions, so I don't mind I chose SS because thats what I could find in my box of scrap metals, I didn't want to go and buy some aluminium just for this. If I make some more for CPFers, which I may do later this year (depending on workload from uni) I'll probably do them in aluminium, it's far easier to machine aluminium than SS. But that is in the uncertain future.

I just finished the tube today, here are some more photos:

O-rings are the spare ones that came with the SR3. It (obviously) feels quite a bit heavier than the original, being Stainless Steel, but not too heavy for its size.
Until I can afford some new AW 18650s, I'm using a couple of Sanyos harvested from an old laptop. Everything is working well, this light really screams with 18650s in it! Hope you guys like it

 

[Essexman]

Dam nice work, well done.

Now go make your GF a small LED light to fit in her handbag, then she'll take note of what you are doing!