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Why Box mods hit so hard.

Discussion in 'Cloud Chasing & Sub Ohming' started by u8myufo, Sep 29, 2014.

  1. u8myufo

    u8myufo Achiever

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    Just come across this and thought I would share,an explanation of adding more batteries for those that may not know what happens.The sound could have been better but still worth a watch imo.

     
    #1 u8myufo, Sep 29, 2014
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  2. Chegs

    Chegs Veteran

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    My first attempt at building a box mod involved use of odds n ends I had laying around.
    One 18650 was simply not enough to overcome the internal resistance of the wires/battery contacts & switch & although it could be used to power a 0.3 ohm RDA there was almost sod all vapour.I added a second parallel 18650 & this meant the atty instantly started chucking out decent amounts of vapour.

    Proof of the internal resistances was demonstrated when the wires I had soldered to the switch kept detaching itself,and when I finally cured this....the switch itself melted internally.

    Fast forward several months & my box building had progressed to use of lipo cells in parallel(bumping up the maximum current draw from 20A to over 80A)and a high power rated mosfet to protect the switches.My first box was now powering 0.1x dual coils with 4 x 1000 mah cells in parallel,and showing just a 0.1V drop and also powering the atty for 30 hours+ on 0.3 ohm builds or 12 hours+ on lower sub-ohm builds.

    I am now using 4 lipo cells(bigger 2200 mah rated 40C cells)with 2 parallel & 2 series,and using ohms law to discover that I would need 0.6 ohm coils to get the kind of wattage I like to vape at with 8.4V.The box containing these bigger lipos is a little on the ungainly side of fucking huge,but as it is plastic it is actually lighter than the 4 x 1000 mah metal enclosures.I have added a little voltmeter to the front as I kept over-discharging the lipo pack and my balance charger refused to recharge the pack,so had to remove the cells & recharge them individually before rebuilding the box mod.I now have a box mod that suffers just 0.2V drop,regardless of how much load I place on the cells and will power my RDA for 14 hours(average)before I start to notice a change to the vapour.

    My biggest issue is finding a happy medium for the wire I use to coil it.If I try using single strands,the fecker will melt instantly even with 0.5mm kanthal unless I make the actual coil very very long(it only just fits under the cap of the Zenith)and despite the driptip being mounted in a delrin insulator,2 or 3 tokes & the fucking driptip is too hot to go near.I have used up all my 0.25mm/0.3mm wire,experimenting with twisted coils so am waiting for my order being delivered of both these sizes as the quad twisted 0.25 was close to being perfect & I wanted to try triple twisted(but had no more sodding wire)and the reel of 0.3mm has gone & hidden itself(or the gremlins have stolen it)as I reckon triple 0.3mm might also be brilliant.

    There seems to be a kind of delicate balancing act needed to create the perfect vape,between resistance/thickness of wire/voltages & number of wires in the twisting process.
     
  3. Chegs

    Chegs Veteran

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    Seedy this video might answer your question as to why 2 x 18650's :D
     
  4. Seedy

    Seedy Vendor

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    What questions that fella?
     
  5. Chegs

    Chegs Veteran

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    On your thread about sx350's, was sure you asked why yihi were offering their boards with this option.
     
  6. Seedy

    Seedy Vendor

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    Nope. Thanks though. Hopefully this will help some people to understand ;)
    What it was was someone saying that the boards need 7.4 and that their batteries fully charged were 8.4.
    They were worried about over loading the chips.
    I wondered why batteries are marked at 3.7 when they are 4.2 fully charged and have since googled it and found out why from here: Why are Li Ion batts labeled at 3.7v, when they charge to 4.2v?

    Thanks though fella.
     
  7. Chegs

    Chegs Veteran

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    Ahh, that'll teach me to actually read threads and to wait until I've fully woken up, lol
     
  8. Seedy

    Seedy Vendor

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    I just watched it and I now need a quad box. Damn you Rich! ;)
     
  9. Chegs

    Chegs Veteran

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    No need for quad boxes, just go for 8.4V and this halves the drawn current, so even shitty soldering of joints doesn't really affect the output:)
     
  10. Vern

    Vern Achiever

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    for this same reason, cars running on 48v (or even 24v like some tractors and trucks) instead of 12v would be simpler too. Thinner wiring, save money etc etc
     

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