Help with fitting Convoy S2 driver

I thought the standard Nangj 105 would fit but the retaining ring on the S2 doesn’t allow chips to be on the battery side. Other than using what they come with stock, what are my other choices for around 2 amps? Has anyone cut the ring’s ID to allow room for the chips?

Just tack solder it in a few places

That was a consideration but the threads would be ruined and replacement would be difficult as the driver is recessed. I’d only solder it after cutting the pill down flush with the driver. I’d rather use the ring even if I have to use the stock driver but I just have the host.

Unfortunately soldering the driver to the pill is what most of us do.

The other option is to stack 7135 chips. Not an easy task but it can be done.

The recess makes it easier to solder—you just have to put a little tac to keep it in the pill—nothing to it—you want to change the driver—at worse use a little copper braid with flux to remove the solder—all mine are soldered

There’s still a resistor that might be in the way. Too bad, the retaining ring seemed like a good idea.

ding ding ding

This is a 602C pill…just tack it down

But the 105C is a bit harder due to the components on the back side

I am at the same point with a S2 host, I found a thread here at BLF with pics of a soldered NANJG105C 8x. I don’t like the thought either ruining the threads of the pill. I’ve already searched for a thinner ring like this but with no success. I will probably use a single-sided driver instead like the Nanjg 101-AK-A1 or the LD25 but the latter might be to high to fit, nevertheless I’ve got one on order. Perhaps I will take the driver I salvaged from the TrustFire A8 I recently modded.

Edit: The current project of mine is a Convoy S3 host and the thread I mentioned is this one: DIY + Review of Convoy S3 Host
Different model, same problem.

Yes, it does look tall. I’m guessing 8mm at most.

If I get the Nlite firmware with the Nanjg 101-AK-A1 from Mountain Electronics, will it have the blinkys removed and PWM increased?

Just for cross-reference: There is a simple way to fit a 6 or 8x 7135 driver to a Convoy S2/S3 pill - just use a Nanjg-105D as Convoy does! I’ve found that by accident - the 6x 7135 Nanjg-105 drivers I’ve got from Fasttech are 105D and the retaining ring fits (after a bit of sanding) around the chips. Simon from Convoy re-designed the bottom layout for this purpose. The downside: there are no stars to choose mode-groups, a compromise that should be acceptable for Newbies like me. Read all about it in this thread:

These drivers should be available at the Convoy/Aliexpress store or here:
8* AMC7135 2-Group 2~5 Modes LED Flashlight Driver (Nanjg 105D)
6* AMC7135 2-Group 3/5 Modes LED Flashlight Driver

  1. Most of us solder when the driver does not fit.
  2. It (soldering) also makes for a better ground connection.
  3. I was dismayed about it at first but what are the odds that you will use the ring again?
  4. Even if you did change the driver or anything within you will solder again.
  5. If you are really intent on the ring then just stick with 4 chips. The power difference is not that great.
  6. If 4 chips is not enough then just get a 17DD FET driver from Mountain with several modes and choose the level that you like.

...........just some thoughts :)

If it’s a brass pill, tacking a little solder at the edges is the easiest solution.

For aluminum pills, where the driver can still fit inside the pill I do the following:

  • File a small notch in the side of the driver.
  • Solder some solder braid onto the edge of the driver then bend the braid so it goes into the notch on the side of the driver.
  • File down the braid for a tight fit. Trim off any excess. The ideal is for the braid to protrude slightly so you get a tight tension fit with the braid making firm contact with the side of the pill adjacent to the driver. If you need to remove the tightly fitted driver later, lever up the edge with a blunt exacto knife.
  • If necessary, add up to three additional solder tabs around the driver. This shouldn’t be necessary if the first one is done right though.

I don’t know bout everyone but if I get the chance to pressure fit the drivers I’d do so.

most driver boards had holes on the ground ring
I usually just tie some wires and force fit the driver to the tube

may not be the best way but with battery installed it usually survived drop tests

Too late, I already soldered in a 105C but thanks, I’ll be ordering some of those anyway. I kinda like the easier mode switching of those drivers. I may never need the hidden blinky modes but having access to them in an unexpected emergency situation would be nice.