You can file the ring to make it thinner and still leave those grooves to screw/unscrew it.
It did that once or twice and it worked!
Despite that, if you want different rings, maybe contact kiriba-ru and check if he has his thinner rings: Low-cost copper pills, spacers, optics, drop-ins (Updated 23/10/2022))
That’s an unfortunate problem with these 7135 drivers. I think I read that djozz reamed out the center of the retaining ring some for it to fit. With the qlite 8x7135 driver the 7135 chips extend right out to the edge of the PCB so there’s no way to use a retaining ring, but with your driver above it looks like the chips are not as close to the edge so reaming the retaining ring might work.
If you don’t want to ream out the ring you should solder the driver to the pill at 2-3 spots around the edge. You want a good connection to the pill both for electrical connection and for heat transfer from the 7135 chips. Soldering to the pill is a bit of a pain; you have to heat up the whole pill very hot in order to get a good solder connection.
Did you file by hand? I was thinking of using a round file and then the Dremel to fine tune.
I used to solder the driver to the pill but it’s a pain to do and an even greater pain when you want to remove the driver. What I started doing was soldering 2 thin wire stranded to the edges of the driver and then press-fitting the driver into the pill. With a little fitting you can get a tight press-fit with a good electrical connection.
Reaming, hey maybe I'll use this tool...
I used it back in the day for porting exhaust manifolds. Yeah! that'll grind that retaining ring now
Hey that’ll work too. I’m gonna give soldering a few hours rest though. I accidently grabbed the hot iron tip! Pain!!! :sunglasses:
I know there are two different kind of 7135 based drivers in an S2(+).
What I call the old Nanjg AK47 or 105C based drivers, and the new Convoy drivers in the OP.
For the first kind I grind out the under side of the retaining ring with a 20mm sferical tool.
Maybe a bit hard to see, but the left ring is original and the right ring is grinded out.
Normally the threads of the retaining ring are not able to reach past the 7135 blocks.
But the grinded out ring is “cupping” the 7135’s and does reach the threads of the pill.
I’m not quite sure but AFAIK the 7135’s on the new driver are placed more to the center.
And thus don’t interfere with the retaining ring. If they do, grind the ring.
The 7135’s are not in harm: the retaining ring only pushes the driver gently in the seat of the pill.
The pressure of the S2(+) tube goes past/around the retaining ring and directly on the pill.
You can CaReFuLlY shave down the corners of the 7135s. Ain’t much stuff in there, only epoxy.
Always want the most pressure against the rings that go around the periphery of the driver, to make solid (ground) contact with the pill/case/etc.
Ideally it would be soldered right to the pill (gotta use the hot end for that, though, not the handle) for best electrical contact, but ain’t too moddable after that.
Yeah those are great tips. I have a set of grinding rocks too. Plus shaving the 7135 should work out. Ohhhh!! I just had and Einstein moment. How about using some kinda tiny circlip! Super fast and easy to remove too. :-)
Sorry, but won’t work.
1/ you have to have a groove inside the pill. That only works fine with 1 size thickness of driver. A retaining ring can be fine-tuned with more precision towards dimensions and pressure.
2/ IF you are able to find a circlip that fits INSIDE a pill, chances are nihill that the inner diameter of it is wide enough to keep free of the 7135s.
With one or maybe a few exceptions, like a piston pen snap ring, or something like this:
Incoming unrelated comment here. But I just wanna say man, it’s been a while since I see a black Convoy S2+
It has always been grey or colored or white but rarely a black S2+ was featured
Thanks for sharing pics
“ Looks like the retaining ring is touching the 7135’s. Can I just leave the ring out?? Is there a smaller retaining ring I can get somewhere?“
It doesnt mind, it will work fine, thats just the ground.
Silly question, why doesnt the flat carry the Convoy brand ?
Never seen that before, except for non convoy lights
The black XML2 8*7135 with OP reflector is the cheapest one on Banggood.,it's $9.99.The driver is soldered to the brass pill
The blue/gray S2+ with SST40 and 5A Convoy driver is/was $13.99 on BG and has a locking ring ,bypassed springs and smooth reflector.There's no chips on the spring side.
In my opinion, 7135s never were a proper solution for a linear driver in a flashlight. Cheap and available, sure, but they don't really deal well with PWM, required to make them output less than full blast, and PWM sucks in a light source anyway.
You can continue dealing with this decrepit stuff, fine if you will. Or you can order the new “SST-40” dubbed linear drivers, Biscotti is now available for them.
I’ve done that several times. Use a marker to color the bit that interferes, then a flat file to notch the lip on the ring. Works fine. There are pictures of that I’ve posted, lost somewhere in the old BLF posts.
EDIT: Aha, bless you SB for your wonderful forum tools.
MTN Electronics: LEDs - Batteries - Lights - Chargers - Hosts - Drivers - Components - 1-Stop-US Source - #8018 by hank is in the middle of a multiple post discussion, and has a link to an even earlier discussion of the same issue.
Special driver ring– $3
16mm ID, 18.5mm OD, can fit convoys with 17mm driver place, my pills, drop-ins
you need to use spring on driver (not brass button) with this rings
Looks awkward but, as I see it, a combination of retaining ring filing until the holes are at the verge or very slightly swallowed, plus driver modification like Lightbringer suggested (filing down the 7135 corners plus capacitor relocation if needed) would result in a very clean, nice looking solution. 
This is my S2+ copper. All my S2+ 8*7135 come soldered in this way.
Lots of good tips and skillful mods done. :-) Now I have to figure out which way to mod it.
Either way looks like not much space down there. Just enough for a rice grain.
Just wondering what’s inside your keyboard 