Yup, Delghi’s work is amazing. 
Thanks for the input guys. The metal lip that is epoxied… would it have enough strength in a relative small epoxy surface area?
If you really want the carbon fiber look without spending $100, take a look at the Spark SF3 and SF5. They both have carbon fiber sleeves, a nice interface, nice tint, and cost around $50 each.
Nice, thanks for the info.
My main goal is to make an extention tube for those who want to use a RRT-01 with a 18650 though.
The CF retaining ring might not be epoxied - it might be machined to a fairly precise fitment, then heated up (and/or the main tube cooled) and stuck on. When everything returns to ordinary temperature, the ring shrinks onto the tube and likely won’t ever come off.
I expect this will be machined in South Korea like your pills, so I understood that this wouldn't be cheap. I'm still in. If you decide to save money and effort by leaving out the cf, I'm okay with that too.
Yes, I’d be more interested if it was cheaper and wasn’t CF…just need it for the functionality.
Haha, adding carbon fiber isn’t expensive at all, here’s a 50cm tube I’m looking at:
I’ll just slip it in and secure it, shouldn’t add too much to the time or cost.
I can of course just make it out of plain aluminium or titanium, but I’m afraid that would not go well with the dark anodized RRT-01.
it would probably be cheaper instead of using a press fit locking ring, to just use a threaded locking ring. tolerances would not need to be nearly as tight that way
Interesting, what would be the design of the locking ring?
An alternate idea that I had was to insert the CF tube, epoxy it, and not use a lip on the other end at all so that the tailcap directly presses onto the rim of the CF tube. Does anyone see any disadvantages with that?
Instead of pressing into the cf tube, chamfer the inner lip of the tailcap and extend it so it covers the end of the cf tube. I hadn't thought much previously about the tailcap though. Will there be a switch? That would be very nice.
Pretty much like a driver or switch retainer ring, but with the threads on the inside, and just have it threaded the same as the tailcap threads. Have the tailcap so it will snug up to the retainer ring and it will lock it in place.
If you have it so the tailcap alone snugs up to the CF, someone could tighten it too much and damage it I would imagine.
Gluing it on and having the tailcap kind of taper over it for the visual look would be a better idea
That’s a good idea, I wonder if that’s how Delghi from CPF did it with his P60 hosts.
I realized that the tailcap end and the battery tube was a solid male piece for the RRT-01, not a female piece like other flashlights.
Here’s a breakdown of the RRT-01 from AKU’s review :
It would be nice if it was cheaper than a Niteye Eye15.
Hey, rrt01 is virtualy identical to the NiteEye 10.
So this tube should work for the NiteEye 10 also.
ETA: Just discovered the NiteEye 10 head works with the 18650 battery tube of the UF-2100 although it doesn't thread over the existing 2100 o-ring but butts right up to it and works well enough.
Anybody got one to try on the RRT-01? NiteEye 10 and RRT-01 should be the same as they are virtual clones of each other.
This will do well enough until this thread pans out a new fitment.
The head of the RRT01 on the body of the Eye15 is a well known way to get 18650’s and the wonder of the RRT01 together.
I didn't know about the Niteye Eye15. I'm still in on this, but now I suppose it'd have to offer a bit more. The cf tube is one thing. I'm still not clear if this is going to have a tailcap with a switch or not. A switch would be a big advantage, especially if the threads were still anodized. Either way, I'd like the lanyard hole to allow the lanyard to be attached from the side. Two holes close together could work. Or do it like the oLight S10.
Here’s a photo of the Niteye Eye15 + the Jetbeam RRT-01 from my local forum:
It works perfectly!
Some have also suggested that a 4mm trimmed Convoy S2 tube and the RRT-01 work well too.
The extention that I’m planning will go between the head and the battery tube, so none of the functionalities would be different from a stock RRT-01.
You can get seamless carbon fiber “sock”. It is a woven tube shaped fabric that can expand enough to slip over a tube.
Sorry, I very badly believed you were making a battery tube replacement even though you clearly said it was an extension tube over and over. I wouldn't be interested in that unless the price was low, and I doubt the price I'm thinking of would be worth it for you. Eye15 or S2 tube seems like a better option for me.
No problem mate, will see how this goes.