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0.8mm kanthal

Discussion in 'Cloud Chasing & Sub Ohming' started by Trungo, May 27, 2014.

  1. gords1001

    gords1001 Achiever

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    Going back to the op.....


    I like the thick wire for two reasons, it takes ten wraps ish per side to see .2ohm - coverage of wick.

    It makes for extremely easy to wrap, robust coils, with a little practice you can wrap micro coils without pulsing. I stick at .2 ohms simply because my favourite cells have a 22amp limit (continuous, I dont buy this pulse limit crap in the slightest), most will scoff but they hold their voltage under load better than sonys which results in longer run times and higher actual wattage. I'll drop to .1 or .05 when my 26700 box mod is finished, 100amp discharge limit anyone?
     
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  2. Geordie Rob

    Geordie Rob Achiever

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    100amp discharge rate omg safty first and all that, another thing that struck me from your post about thicker wire and robust coils, these parallel coils first time of using there solid way more robust than doing the same amount of waps with the same guage wire for sure. Thanks for your post.
     
  3. gords1001

    gords1001 Achiever

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    Two 26700 molicells in parrallel technically have a limit of 120amp.......I am being safe, just not very sensible. I would expect to need to turn a 30mm dripper or genesis to really make use of that limit as your pushing a 22mm atty right to its limits at that. The igo m might take it but I would want to replace all the insulators and o rings with high temperature versions and its still not go much surface area to shed the heat, I would want a few fins on there to increase surface area, never mind the extra capacity you would add with the larger juice well.


    Not that I've thought about this or owt...
     
  4. Chegs

    Chegs Veteran

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    The latest 2 box mods I've built contain 4 20C rated batteries in parallel which according to various websites means I can safely draw 80 amps from my packs. I don't fancy trying it though as I'm already experiencing solder connections failing occasionally and needing even greater care taken when fixing the failed joints. I believe there are some solder free types of connector available(for r/c modelers)but these add to the cost of my mods and aren't a must have requirement for my preferred vaping power. I might build one with better connectors purely for cloud chasing eventually, but only if I can't think of something else to do at stupid o'clock in the early hours:P

    Sent from my SM-T210 using Planet of the Vapes mobile app
     
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  5. gords1001

    gords1001 Achiever

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    The melting solder connections may be down to not getting a good joint - not good connection = resistance = heat. I've used deans connectors at 200amp, and foe much more prolonged periods than for vaping in rc cars and planes, you do need an iron thats at least 40watts and preferably higher.
     
  6. Chegs

    Chegs Veteran

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    I tend to use my 100 watt gun,and then test for voltage drop as I don't possess anything more reliable for resistance under load testing.Of the 2 box mods,the one with a 0.15 drop is the one most often suffering failure of the joints(usually at the 14AWG to MosFet)and I doubt a Deans type connector would fit on a MosFet leg. :P
    The 2nd box mod only suffers 0.1 drop,and hasn't required repair of the connections (yet) even firing 0.1 ohm coils but as this kind of wattage ruined the taste of my juices I don't need to alter it.

    The mental cogs are grinding slowly,in the hope of finding a solution to 14AWG-MosFet joints for an "ultimate cloud-chasing" box but I doubt I'll find one without buying different MosFets.
     
  7. gords1001

    gords1001 Achiever

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    Use a few mosfets in parrallel to share the load and heat sink them. Now I know what connection you are on about I can easily see them getting too hot for solder.

    Get thermal paste from a computer shop and somthing to wick the heat away from those mosfets and it should solve your problem.
     
  8. Chegs

    Chegs Veteran

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    The MosFets I use are so fecking tiny that attaching them to a heatsink (though would do the job of removing the heat) is pretty fecking difficult.The only method I can think of is creating some kind of clamp,and having had a hunt through my (sparsely populated) spares bin isn't possible atm.
    DSC_0287.jpg MosFet alongside 510 drip tip for comparison
     
  9. sparkyjuice

    sparkyjuice Achiever

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    is that a smd ?
     
  10. gords1001

    gords1001 Achiever

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    I would think so looking at it.

    Brass, solder paste and heat gun or blow lamp on opposite side would be my solution, however you do it, heat sinking would be the answer.

    I'll be looking for power fets as they are designed with heatsink fitting in mind :)
     

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