Yep. All doable. Unsure about thinning the board but it’s worth a shot. Your firmware could make this awesome. Perhaps you can program an extra board?
My solder blob is very short. This light is a few mm too short. You can use imr 14500 but protected cells are likely too long.
I should receive this AA brass light in a few days. I plan to replace the driver, but how deep is the driver cavity ?
I had hope that thje ReyLight pineapple driver would fit maybe ?
I don’t have the light anymore. It’s a tiny cavity that only fits single layer drivers of 14mm or less. The ReyLight driver is too tall (double layer) and too wide (14.55mm). You could try filing down to 14mm but the ground ring on the ReyLight driver is VERY narrow. Doesn’t matter since it’s too tall.
It’s a nice, small light, but I think it’s actually too small. No space for modding etc.
What about MTN-15DDm? It’s single-sided, looks like it could be filed down to 14mm diameter, and the component side looks pretty low-profile. FET + 7135 Driver - 15mm - MTN-15DDm
I filed down a 5x amc7135 board from mtn to 14mm (it only had 1 chip and was reconfigured to be single sided). It fit. If that board can be filed to 14mm it should fit.
In case anyone stumbles across this in the future, I tried both the MTN-15DDm and their FET15-SS which is fet-only. Neither are workable in this light. You'd have to sand off at least the entire ground ring around the circumference to get it to fit, including all the vias. (I got bare boards and actually sanded them down rather than destroying populated ones.) I'm considering laying out a very simple mcu+fet board for this as I don't care about 1.5v AA compatibility, I just want fast pwm and configurable modes.
See my update here -- pd68's 14mm fet+7135 layout on oshpark works well, even with a tiny85 crammed on:
https://budgetlightforum.com/t/-/27787/83