Snuffy smith box mod (cheap)

[designer43]

My objective was to spend as little as possible.
I bought a XL4015 dc-dc buck regulator on eBay. It has a voltmeter with two switches for disp. off and in/out volts. I ran a 2s1p 850 ma lipo 25c into it scrounged from quadcopter. The EGO connector was scrounged from a dead battery. The fire sw. from a pcb mini switch, no idea the current rating, My wife donated an eyeglass case that had room for everything.
Lo and behold, it works! Vapes much better than the EGO 1100 batteries,
There is an issue maybe somebody can solve. With the Atty unscrewed, the LED voltages display properly. With it screwed in it's totally blank, Measured no load into the reg is 7.7v, and under load it's 6.9v. Is this much drop killing my on board display?

Edit, type of lipo

 

[Zamazam]

No idea. Can you sketch out a quick schematic so we can look at it?

 

[designer43]

Nothing exotic. B+ to sw to buck reg pcb+. B- to reg. pcb -
Output to EGO connector.
Maybe found a clue. A 2s1p 4000ma 25c lipo @ 8.4v will make the on board middle digit flicker dimly.
I guess the buck reg ic works with low voltage but not the LED circuit. I know I need a heftier fire sw.
The whole mod consists of four parts.

Edit, lipo type.

 

[designer43]

The problem was the tiny pcb switch.
My red Harbor Freight meter on the 10a scale across the switch effectively shorting it read 0.0, however the on board voltmeter lit up and read 3.4 volts! It promptly went out when the lipo couldn't supply enough voltage to the regulator.
Looks like my lipo just isn't up to the task .

 

[MrScaryZ]

My objective was to spend as little as possible.
I bought a XL4015 dc-dc buck regulator on eBay. It has a voltmeter with two switches for disp. off and in/out volts. I ran a 2s1p 850 ma lipo 25c into it scrounged from quadcopter. The EGO connector was scrounged from a dead battery. The fire sw. from a pcb mini switch, no idea the current rating, My wife donated an eyeglass case that had room for everything.
Lo and behold, it works! Vapes much better than the EGO 1100 batteries,
There is an issue maybe somebody can solve. With the Atty unscrewed, the LED voltages display properly. With it screwed in it's totally blank, Measured no load into the reg is 7.7v, and under load it's 6.9v. Is this much drop killing my on board display?

Edit, type of lipo

Hey can you build me a Snufy sniffles box thingy too?

 

[designer43]

Hey can you build me a Snufy sniffles box thingy too?

You're pulling my leg, right? The case is vinyl wrapped and raggety inside. The switch will probably smoke any day now. Notice the homebrew balance plug connector? Not recommended running anything off balance plug. The lopo's I own are all slightly puffy. The EGO connector looks to have 30ga wiring. The board and battery are only kept on place with sheet foam. I'd be in jail if I sold anything like this total abortion!
The whole mess only cost me $3.14 for the regulator, and IT does a shitty job.
I guess my case isn't gonna hold my BIG 4000ma battery ☺

 

[MrScaryZ]

You're pulling my leg, right? The case is vinyl wrapped and raggety inside. The switch will probably smoke any day now. Notice the homebrew balance plug connector? Not recommended running anything off balance plug. The lopo's I own are all slightly puffy. The EGO connector looks to have 30ga wiring. The board and battery are only kept on place with sheet foam. I'd be in jail if I sold anything like this total abortion!
The whole mess only cost me $3.14 for the regulator, and IT does a shitty job.
I guess my case isn't gonna hold my BIG 4000ma battery ☺

haha I like it primitive but functional I like that Lipo that is cool.. maybe cheap but it works