Before this, I can’t supply more than 3A from my bench power supply. Somebody posted about this LM2596 from eBay and got an idea to create at least 4.2V/6A Power Supply.
Have tested it on an XML at 4.5A. Currently configured 2 modules in parallel (using shunts).
Each can be individually calibrated.
I wonder, would it be possible to use a single pot for all 5 modules?
I don’t see why it would not be possible
but it would be nice to use one of those 10-turns pots for precise settings.
Btw, I like the idea of DC-DC paralleling tivo 
It’s not without a peril thought.
To have the supplies work together and not against each other, output voltage has to be set very closely together. (But regulation loop still might not like that)
Paralleling as much as 5 might be tricky at high load because current share might not be equal. I would keep an eye on them.
Besides that, the build looks quite sexy I have to admit.
It would be pretty easy to check, I guess. Remove all the original pots, then measure output from each one one at a time using the same pot without changing its adjustment. If any of them are slightly off, couldn't you figure out a fixed resistor to use on the ones that are off, and then use jumpers to tie all the boards to a common pot?
edit: I'm using a different version of a similar board in a 100w desk lamp conversion: https://budgetlightforum.com/t/-/20547#comment-444346
At least the outputs should be trimmed as close as possible.
Load sharing symmetry can be improved by adding some resistance to each output. Maybe tivo meant that by ‘using shunts’.
There are two shunts for each module. The left side of the berg stik terminals are all shorted and connected to the orange jack at the bottom. I remove the shunts to adjust them to the same level as much as possible. The output can be 1-5 modules in parallel. So far so good and have not noticed warming up on the LM2596 when being used.
Great, hope they keep behaving nicely. 
Please keep us up to date how it works out with higher loads/more modules in use.
something like this.
Should cost you less than 4 of these but adjusting output with a single pot would be priceless.
If you are going to use it just for 1 led, then
http://www.ebay.com/itm/DC-High-Current-Power-Supply-10-14V-to-2-5-5V-15A-Peak-20A-Buck-Converter-/130956963023?pt=LH_DefaultDomain_0&hash=item1e7da4accf
Or try this.
http://www.ebay.com/itm/15A-DC-DC-Converter-Buck-Adjustable-4-32V-12V-to-1-2-32V-3-3V-5V-24V-Power-F-car-/271210631080?pt=AU_B_I_Electrical_Test_Equipment&hash=item3f2569cfa8
It is always problematic when connecting switching power supplies in parallel. There was a guy somewhere (probbly here on BLF) who connected the drivers in parallel and lost quite some efficiency. My 2 cents.
2596s are 1.18$ on ebay. Damn that’s cheap.
Good find Lunatictr! I’ll look at them if my DIY unit doesn’t work at current above 6A.
Yup! it’s really cheap for a DIY unit.
I’m going to add a switched jack and a reverse clicky on the board for testing LEDs and drivers.
I was wondering do this voltmeters have parasitic consumption (they obviously require some V to work), how much volts do they pull?
For example, if you set the output to 4.2V and then add this voltmeter how much will it eat out of the 4.2V?
Input power to the mini voltmeter will be coming from the same input as the LM2596. As for current consumption for the output, I’ll do some measurements when my order comes in. Should be in the mA range. You can always subtract it from the LED current.
And with this, you can measure voltage, current, power, capacity of the batteries until they drain or the time when the led overheats and burns, all at the same time J)
http://www.buyincoins.com/item/11856.html
How about one of these (assuming you can run the modules in parallel)? Would be nice to get those numbers at a glance without having to move leads or jumpers around. http://www.ebay.com/itm/181048990354
Check out the rest of that seller's items, some stuff I never knew I needed in there...
Added Battery holder, switch and heat sinks. :beer”
Nice work Tivo! That thing keeps evolving and it will have eyes and a duck bill soon 