Odic Force OFL74 405nm Boost Driver - more than 500mA current?

I just did a 405nm 12x build using this driver to supply ~400mA from a CR123. The pot seemed to max at 400mA, before immediately jumping to like 900mA. I'm guessing that in reality, I turned the pot too far. Turning it back brought me back to the ~400mA upper limit, luckily with no damage to the diode.

But I was thinking - is this a board that could be modded to hit a higher range (for powering a 445nm)? Does anyone have any experience with that? I'm not entirely certain, but it doesn't look like any of the components are fixed resistors that could be changed

Variable Current Step-up (Boost) 405nm Laser Driver Board - Detailed item view - OdicForce Lasers Online Shop

If nothing else, would there be any reason you couldn't run two of these in parallel to supply 1A (for about half the cost of a Flexdrive) ?

Yes. There is a good chance running two in parallel could break them.

If you are interested you could try doing this:
Set the potentiometer so that you are getting close to the lowest current. Power the circuit off and measure the resistance between the potentiometers middle and (pick one) of the potentiometers sides.

Then re-power the circuit and get a high current out of it. Re-measure the resistance with the circuit powered off again. If as the resistance gets higher, the current gets higher, you could change the potentiometer to one higher (to give you a larger current range) or put a resistor in series with the potentiometer (to shift your current range up).

This sort of modification is likely to require some knowledge of Ohm's law.

As an example, if you measured that 20mA is at 1kOhm and 400mA at 20kOhm, you could try adding a 20kOhm resistor to give you a new range of 420mA to 820mA.

I think (truthfully) a deeper understanding of the nuances of driver design may be beyond me. If this isn't a goofy question to ask - could I trouble you to explain why running two in parallel might be problematic? (I trust your opinion, I'd just love to know why)

Only because I have no idea how these particular drivers work. For example if they used feedback to keep their current constant but otherwise had slightly different parameter values, then running two in parallel could cause them to overload/oscillate or something.

It could work totally fine. Try it in a dummy load first.

Will do

I'll report back!

Strange results:

Running two of these in parallel seemingly did NOTHING.
IE - exactly the same current.

I was suspicious that one of them just didn't work, so I unhooked each of them from the circuit one at a time. Both seemed capable of running a 405nm test load at around 300mA on their own. Combined in parallel, it appeared to STILL only provide 300mA.

Very strange. More testing required?