Want to turn this junk light into a boss, in memory of my friend

So I have this light.



It's some junk no-name 6P/Z2 clone. I don't know who made it, or where it was bought from, only that it belonged to a 12-year-old young man, a dear friend of my family. Before he was tragically killed in an accident this past summer, he engraved his name on a flattened area on the battery tube (not shown in the photo).

It had been left at another friend's house, as kids' belongings often are, and after the accident it wound up being handed off to me. I'm the closest thing to a flashaholic in my friend group, and I guess I've been vocal enough about it. Because of the engraving, I'd really like to restore it into a solid, useful light, and present it to his family.

It was originally a 2xCR123-powered incandescent, but the reflector and lens weren't spec'ed to handle the heat. The lens is distorted in the center and the plastic reflector is cracked and burned around the base. The switch boot is worn through and cracked, and the plastic body of the switch itself (inside the tailcap) seems to have also suffered some heat damage. And the bulb is burned black. But the head, body, and tail seem to be pretty solid metal.

Though it's a P60 look-alike, the head has a smaller inside diameter (22-23mm as opposed to the 26.5 of a P60). I can do some machining to the light, but not that much. The lens window, however, is exactly the size of the reflector cavity (~19mm) on Malkoff's M61 drop-ins. I've wondered whether I could turn down the OD of one of the Malkoffs to 23mm without damaging it - that's roughly the type and quality of engine I'd want to use. I have a source for a good glass lens that will fit.

The body will accept a 16650, and I'm fairly certain it's thick-walled enough to be bored for an 18650 if I decide to risk that. I want to buy a couple of the batteries with built-in USB recharging so my friends don't have to buy or keep up with a separate battery charger to be able to use the light all they'd like. The tailcap seems to be sized and threaded exactly like the SureFire Z41, so a McClicky upgrade switch kit should fit. The only problem is that the switch boot seems to be ~18mm instead of the standard 14mm. So...

• Any advice or suggestions?
• Any experiences shrinking a P60-type drop-in, or other recommendations for an engine and emitter?
• Any idea where I might find an 18mm switch boot?

Thanks.

I don't have any real input, but this is cool what you are doing for that kids light.

It sounds almost like you could work with making an engine that fits in a sleeve, then into the body rather than a traditional P60. That would allow you greater freedom to play around with the lens as well and find one that fits in well along with a reflector/optic for it.

I wouldn't recommend you bore it out, just in case there's a section with a thinner cross-section than you expected and it's a weak point.

As for boots Kaidomain has a lot of that (sorry to the mods if it isn't allowed to mention certain retailers like this) and i'd recommend you check with them and others like the plethora of sites from the far east having that type of stuff for sale.

LRJ88 said:

It sounds almost like you could work with making an engine that fits in a sleeve, then into the body rather than a traditional P60. That would allow you greater freedom to play around with the lens as well and find one that fits in well along with a reflector/optic for it.

Click to expand...

Maybe so. I'd love a mostly pre-fab solution, just because I want this to be solid. I've done electronics and a little bit of machining before, but this would be my first time building something like this.

I wouldn't recommend you bore it out, just in case there's a section with a thinner cross-section than you expected and it's a weak point.

Click to expand...

I'm probably going to go with your recommendation, since I've noticed that there are 16650s now with the built-in USB charging option. I don't want to risk fouling up the body, since that's the irreplaceable part with the engraving.

As for boots Kaidomain has a lot of that

Click to expand...

THANK YOU. I'd been searching for "switch boots" and not finding anything. Seeing that they're called "silicone tailcaps" got me to many more useful results.

You can get Malkoff's SureFire drop in. That should fit. And make an excellent light. Or a solarforce or edc+ drop in. They have replacement lenses if you need one.

Cool that you are doing this for the family.
I would keep it as a 16650 torch, and I like the idea of the USB chargeable cells. This is going to essentially newbie owners, keep it simple.

If you don't find those boots, I have some I can send you. Plus would arrive much faster than Kaidomain...
14mm stock surefire size on left, 20mm on right.

UPDATE: Project complete, except for a little cleanup!

Well, this took quite a while longer than I expected. When I began to get serious about the re-build, the first thing I discovered was that the tailcap was not, in fact, Z41 compatible. So a pre-fab switch kit was out of the question. I went ahead and ordered new switch boots from kaidomain as LRJ88 suggested, and a bare McClicky switch.

I started by pulling the old lamp holder, cracked reflector, and warped lens out. Gene confirmed that I should be able to turn down one of his P60 drop-ins without damaging it, so I ordered an M61W from him and a new UCLp acrylic lens from flashlightlens.com. A helpful friend volunteered some lathe work.

[Turned-down M61W next to another unmodified Malkoff I own]


That got the head working great, but the tailcap and switch was still an issue. Long story short, I wound up 3d-printing a spacing and fitting collar for the McClicky, drilling out a stainless washer for the contact ring, and using the original threaded retaining collar. That solved the problem of having to figure out thread compatibility.

[New tailcap innards, minus the switch boot]


[McClicky in 3D-printed collar]


Threw a 16650 down the tube, and it's off to the races. Unfortunately, Amazon had stopped selling the Weltool USB-rechargeable 16650s I wanted, so I had to order from Banggood. Which, of course, was going to take 8-10 weeks in the time of coronavirus. So I'll probably wind up giving the light with 2xCR123, and pass along the rechargeable when it arrives. The anniversary of my friend's accident is near, and it seems like it might be appropriate to offer the light in conjunction with that.

[Success!]


Thanks, again, to everyone who offered advice and pointers!

Very kind and thoughtful of you, and thanks for sharing. Looks like you did some solid work!

What an awesome thing to do, you should be commended! I am sure the family will very much appreciate it! Great work.

I'm happy to see this turned out just swimmingly, i can only say that he would have been proud to have seen his flashlight be turned into such a little tank.

Great job!!!

:thumbsup: Bravo :twothumbs

Very kind and good job! :thumbsup: