s2+ with xhp50.2 h1-a driver

Hey guys! So i built an s2+ with the old xhp50 and xhp70 aswell, but the xhp50 seems bright enough for me and fits better too. I liked the light and everything, I was using a modded fx-17A driver at around 3.5-4amps, using 2x 18350's. Now I got so tired of the poor batterylife of the 18350's, so I was thinking what if I fit an H1-a boost driver to use a single 18650? it fits in the head fine, but would need to solder it underneath the pill somehow or make some sort of adapter! I will be using the stock pill and a 16mm kd board xhp50.2, 2600 lumen should be plenty for me. I know the pill and light itself isn't great at cooling, but I would only use high modes in bursts and lower modes otherwise, it seemed to work good enough at cooling with the xhp50/70 using a fx-17a. What do you guys think of this doable? How would I go about doing this? This idea just came to me lol! What do you guys say?

Can’t help with the question you have hannesremo, sorry, but I’d like to ask you which reflector did you use with those leds! Did you use the stock OP or SMO reflectors from Convoy S2+?

Thank you and good luck with the mod :wink: Show us some pics then :wink:

Been done a few times.
I did something like it, used a dremel to fit the driver and solder it in place.

Worked ok-ish…

I used the stock op reflector, too small for xhp70, block half of the dies, perfect with xhp50/50.2

Some 20mm x 1mm brass or copper tube might work cut and filed to size and soldered.

I did make a carbon fibre light with an MT-G2 and H1-A driver which works fine but like you said just watch it on high mode although your aluminium host will handle it better CRX Carbon Fibre MT-G2 Flashlight

might try that thanks!

Thanks for the answer :wink: Good luck with the mod!!

So why would you need to solder the h1-a driver into place? Im thinking of doing this build myself.

Hannesremo, you should perhaps try fitting in a Nichia 144AM inside of the Convoy.

Clemence has Nichia 144AM 90+CRI along with a 16mm MCPCB.

LED (the one I picked): https://www.virence.com/product-page/nv4l144am

Reflow service (if you can’t do it yourself): https://www.virence.com/product-page/led-reflow-and-or-soldering-service

MCPCB: https://www.virence.com/product-page/vr16s1

Because there’s no other way to secure the driver.

Even in a stock Convoy the double-sided (Nanjg 105) drivers are soldered to the pill at 2 spots on the edge.
I believe only the single-sided (AK47) drivers were secured with a threaded retaining ring.

The stock S2+ driver cavity is only 17mm, but the H1-A driver is 20mm. hannesremo said the driver will fit into the tube of the head, but not down into the stock 17mm driver cavity in the pill.

So a method of fitting and securing the driver to the pill is needed because it’s not going to just fit in like the stock driver.

  • Lowtech replied that he used a dremel to fit the H1-A, but he didn’t specify if he resized the driver itself or widened the opening in the pill, (or maybe he did both)
  • CRX suggested using a piece of 20mm x 1mm copper or brass tube cut and filed to size and soldered. I assume he meant tubing with a wall thickness of 1mm, to create a new “ledge” for the driver to sit on. I think the driver can’t sit on a ledge much wider than 1 mm to avoid contact to the components that sit near its edge.

Sounds like a tedious job either way, I’d like to know what hannesremo did, if anything yet.


It may be possible to use an adapter like this if its diameter could be reduced to just under 21mm, creating a 1mm ring similar to what CRX suggested.
It has an internal ledge for the driver to sit on. (I measured 21mm I.D. in the S2+ head)

Jensen567 posted (in a different thread) that he fit an H1-A into a S2+ host, saying he “machined out the driver pocket”

This thread: (post #3111) What did you mod today? - #3109 by Jensen567

Here’s a photo from his post:

This is very interesting, thanks! I had no idea know a quad-die Nichia even existed! I also need to look into this.

That sounds like exactly what I did ^_^. Placed a Nichia 144 inside a Convoy S2+.

Please see my build thread here: https://budgetlightforum.com/t/-/50373

I should note that the Nichia 144 dies have a little bit of an uneven phosphor coating, so I recommend a TIR optic to help smooth out the light to avoid the 'fried egg' yellow centre portion of the beam. The result is very even and nice :).

It’s very good indeed.

Also works with a heavily textured OP reflector, like the one in my Haikelite MT01, the beam is just beautiful. I love the tint, high CRI, and deep red saturation.

When I’ll have the copper washers, I’ll finally post the mod on BLF.

BTW loneoceans, if I remember, your boost driver is open source, yes?

Absolutely! Once it's done it'll all be up and hopefully documented! I'm still changing things here and there at the moment, but all the basic functionality seems to be good. Meanwhile do check out my previous GXB17 and GXB20 projects - both the threads and my webpage have hopefully a lot of detail on how they work :), so I'll be doing the same for these new drivers.

Thanks for the link, real nice mod!

When they’re finished would I be able to buy some drivers directly from you?

He probably won’t sell the drivers pre made.

Selling the boards, and then buying all the parts is what I would do, and then build it myself.

I read something in another thread today which gave me a new idea for this mod, for the issue of securing the H1-A driver.

I could get an 18350 tube (around $2.00) and cut off a short ring from the end of the threaded portion, make a few tool notches in it (for installation/removal) and use that as a retaining ring, it would be real thin too, so it should clear any components near the edge of the driver.

Does that sound like a viable idea/method?

What driver did you use for this?