Help with a diy mod

[jock1092]

So I built another parallel box since I got better at soldering ( at least better at planning it out) and had an issue when I tested it.
Basically the switch locked in, but not on if that makes sense.
It worked for about a second.
I had a 0.33 coil from my smpl set up since I know one battery is fine with it a dual should handle it.
What I'm wondering is, I used a Mosfet and a low amp switch - could it be possible I made a short or bad connection that caused it to bypass the mosfet?
What is wondering is if I overloaded the switch.
Or is it just that a recycled switch I've soldered about ten times now had enough of me?
Usually I'd just tear it down and start again but I made the mistake of epoxying everything in place already and just replacing the switch will be hard enough for me.

 

[Miss Pepper]

@stuartd @joe clay can you help?

 

[Loco]

Too much heat on the switch (from repeated soldering/desoldering) could cause it to fail. I'd guess this is most probably the cause of your issues.

To double check this is the fault you can always disconnect the wires to the switch and touch them together to 'manually switch' as a quick indicator that this is definitely the issue.

Best practice is to tin the contacts, let it cool, then solder the wires (pre tinned) to the switch. Keep it short and sweet and you will be all good. Use the same technique with the mosfet or any component that can be heat sensitive.


p.s. Just to check, you did use a resistor with the fet?

 

[jock1092]

Too much heat on the switch (from repeated soldering/desoldering) could cause it to fail. I'd guess this is most probably the cause of your issues.

To double check this is the fault you can always disconnect the wires to the switch and touch them together to 'manually switch' as a quick indicator that this is definitely the issue.

Best practice is to tin the contacts, let it cool, then solder the wires (pre tinned) to the switch. Keep it short and sweet and you will be all good. Use the same technique with the mosfet or any component that can be heat sensitive.


p.s. Just to check, you did use a resistor with the fet?

Yeah 15k resistor on the mosfet from my first build, most of the mod was just recycled from the last huge box I put it in.
I'm hoping it was just damage from the bad soldering and de-soldering of my first few attempts.
I've tested it without the switch by touching the wires and it fires, and I've tested all the connections I can in various places to check for shorts and found none.
In more wondering - if I damaged the mosfet could that allow the full current to cross the switch or would that just stop the entire circuit

 

[Loco]

Nice one, pop a new switch in and you should be good to go. Doesn't take much to overheat a switch in my experience, especially when repeatedly soldering them.
Heat will increase resistance, and most fets will fail open. Do you have a VM you can use to check what output voltage you are seeing?
I too have reused a lot of parts with my practice builds to keep costs down. In fact I am pretty bad for ripping apart perfectly good completed projects in the name of 'improvement'. Have fucked a few switches in my time, but I am yet to mess up a MOSFET fortunately, but should be easy to see if its not playing ball.
Good luck, and pop up a pic when you are finished

 

[stuartd]

just what loco said it sounds like you killed the switch and like loco i`ve done that plenty of times aswell soldered it all up and then nothing so unsoldered everything to find it was the switch at fault. one other thing i wouldnt go that low with a paralell mod even if it is a dual setup i usually stay above 0.5 ohms with a paralell dual setup

 

[jock1092]

Nice one, pop a new switch in and you should be good to go. Doesn't take much to overheat a switch in my experience, especially when repeatedly soldering them.
Heat will increase resistance, and most fets will fail open. Do you have a VM you can use to check what output voltage you are seeing?
I too have reused a lot of parts with my practice builds to keep costs down. In fact I am pretty bad for ripping apart perfectly good completed projects in the name of 'improvement'. Have fucked a few switches in my time, but I am yet to mess up a MOSFET fortunately, but should be easy to see if its not playing ball.
Good luck, and pop up a pic when you are finished

But the new, nicer switch today and fitted it all is working great now.
I'll pop up some pics later as still got a bit of tidying around it to do before it's ready to vape with ( just now its working but not done the insulation or fixed the on/off switch anywhere)

 

[jock1092]

So all done now just waiting for my batteries to charge and give it a good test beyond a couple of "does it work" wisps.
Not the neatest of jobs but all the connections are solid and after sealing and insulating any potential shorts feels pretty sturdy.
Might just replace my tube mechs with this since its the same voltage minus the hybrid adapter that only accepts one of my rda's.

 

[jock1092]

just what loco said it sounds like you killed the switch and like loco i`ve done that plenty of times aswell soldered it all up and then nothing so unsoldered everything to find it was the switch at fault. one other thing i wouldnt go that low with a paralell mod even if it is a dual setup i usually stay above 0.5 ohms with a paralell dual setup

I thought it would be series mods to stay above 0.5 due to the higher voltage while parallel gave longer battery life and higher amp limits?
My thoughts on this mod is as a replacement to my smpl and dotmod clones down to them being hybrid and having no locking systems, while I plan to run it under the same limits as I would for them ( treated as a single cell rather than trusting it to split the load)

 

[Loco]

Nice work man, SUCCESS! I'm glad you got it going. Fuckups promote learning/progression, so it's a good thing in a way.

My suggestion for your next mod (i'm sure there will be one!) would be to run the contact connection of the positive tabs along the sled (give you some more space) and to use stranded wire to allow the 510 (+pin) movement/adjustment without putting so much strain on the connections.

Also, flux is your best friend when soldering, helps keep things short and sweet, and your connections nice, fresh and shiny (though most look fine IMO)

Re: builds as long as you stay within your amp limits for the cells/fet your good to go. I'm with you, I'd take a box like this over a unlockable hybrid tube any day!