DNA75 vs DNA200

[dl12345]

I believe I stated, erroneously, in a previous thread, that my temperatures with the DNA75 were the same as my DNA200s (two of them, boxer and wismec modified with a FDV v4).

In my defense, this was a day after I acquired the DNA75. Since then, I've had more time to compare the two.

At risk of offending some people here, I think the DNA75 is crap, in a word. It requires about 25 - 30 celsius higher temperatures with the same atomizer and coil. In addition, the vape with my 200s is far denser and richer than the 75, even at a temperature setting about 25 celsius lower.

With the identical atomizer, juice and coil.

I've fiddled with the 75 until it shows the same ohms as my 200s, but still the experience is vastly different.

Anyone else with anecdotally similar experience?

[dl12345]

Incidentally, all have the mod resistance set correctly using a copper short-out 510 pin. All hav ehad the case analyzer run and all have correct battery profiles. And they're using the same profile. Perhaps it's down to the 510. The only difference is that my 200s use a decent 510 connector and the VT75 uses a substandard part

[VapingBad]

I find the temps the same (Ni, Ti & SS), but with higher wattage or larger coils that benefit from the extra preheat grunt the 200 & 250 have definitely have an edge.  Also 75s tend to run from a single 18650 or worse a 26650 that have far less grunt and more voltage sag than 3s cells which can suffer if the battery connections are poor, but a good 18650 with good connections works very well.

[retird]

I run my 75's and 200's mostly under 40 watts and around 420F with about 60 watts preheat with SS316L material notch coils and notice no difference between the 75's and the 200's except battery life between charges which is understandable because 1 battery versus 3 in series... Neither the 75 nor the 200 are crap in my books. I run my coils at the same wattage and temp on both the 75 and the 200's.  

Have you ran case analyzer on your devices?  May help if the settings were never put in correctly by the device maker.

[dl12345]

Yep, case analyzer run on all three, both 200s and the one 75. Likewise mod resistance has been set with the aid of a plug on all three devices.

To the point of the single 18650, I keep wondering if this is the weakness myself; I use a single Sony VTC5A which definitely shows significant voltage sag with escribe, far beyond that of the multi-battery 200s. I'm tempted to jury-rig a multi battery setup for my 75 just to see if this makes a difference. I should probably do this before condemning it out of hand...

I have used alternate batteries for the 75 just to eliminate the possibility that the battery is bad (an LG HG2 and a Samsung 25R)

[Spector NS5 RD]

what's the question? how close is the 75 to the 200 in terms of ohm reading / temp setting/ wattage setting (with respect that the 75 is only.......75w)? is it a Skookum Choocher?

i found that my DNA 75's perform almost identically to 200 in TC as long as the cold res is the same and i'm using the same material profile. only thing is, i can't get the preheat power i like with the higher wattage 200/250 but found out almost all of my dual coil TC builds use about 60 - 75 watts to maintain my set temp, so it's just not as fast to ramp up. so far, on my work mod (SMY SDNA75) i have dropped it kabillion times spilled pretty much everything from e-juice and water to pvc primer and glue and flux (and the button surrounds are crusted with pipe dope). it's always getting filled with dust of various nature, sometimes metallic. i think i have over 40k puffs on it, i haven't checked in a while.
keeping the gas pedal to the floor (75w preheat / 11 punch / 2 secs) 75w to maintain, battery life is as expected. A Sony VTC5A lasts about 5 hours (8am - 1pm). a second cell gets me to home base. only gripe, wished the 75 remembered refined resistance when replacing the cell. i have found a work around, by placing a USB "umbilical cord" into mod while i change out  the cell it keeps the board awake while the cell is being swapped out.

[dwcraig1]

My SMY SDNA75 lives an even a tougher life than Chunky's although in a different way, I gave mine to my wife and it still works. She takes chain vaping to a whole other level.
On the serious side I noticed no difference between 75/200 as I only vape at 45/35 watts.

[Wayneo]

Hah, my SMY SDNA75 also lived a severe service life in the hands of my wife. I've rescued it and it's still in surprisingly good condition. I'm very surprised the rubberized finish still looks mint. My VT133 has the cheapest paint quality on the battery door and looks like a beater, but the body is fine. Luckily I have a spare door. They're all setup with the same materials and profile settings. I don't notice any difference at all between any of them. Mainly a SS430 or Ti vaper, lowest build around .1 usually.

With the same coil build specs I'm finding 430 heats up twice as quick as 316 and Ti about 50% quicker than 430.

[dl12345]

Wayneo said:

Hah, my SMY SDNA75 also lived a severe service life in the hands of my wife. I've rescued it and it's still in surprisingly good condition. I'm very surprised the rubberized finish still looks mint. My VT133 has the cheapest paint quality on the battery door and looks like a beater, but the body is fine. Luckily I have a spare door. They're all setup with the same materials and profile settings. I don't notice any difference at all between any of them. Mainly a SS430 or Ti vaper, lowest build around .1 usually.

With the same coil build specs I'm finding 430 heats up twice as quick as 316 and Ti about 50% quicker than 430.

I tried some 430 but didn't get very good results as the steam-engine profile didn't seem to match the material. I got mine from Crazy Wire Company. Where do you source yours? I'd like to give it a try again as I get better results with SS304 than with SS316L, so the improvement should be even more marked with SS430

[dl12345]

I noticed in the last day that when my 75 goes to sleep and wakes up, it resets the resistance as if I am putting in a new coil. For some reason, when doing this (as opposed to having a new coil put in while the device is awake), it appears to consistently under-read the ohms. It only does this when going from a sleep state - my two DNA200s and ohm reader show the same ohm readings, as does the 75 when I put the atty in when the board is awake. If I then take out the atty, reset the resistance with a much higher or lower ohm coil and then put it back in, it reads the original resistance, not the lower value that it did from sleep state. Since the difference amounts to about 0.01 ohm, this would certainly cause a weaker vape. 

I noticed this post from FairCold and have done the same now to my VT75 nano, as it also had a slightly uneven 510 connector pad - almost as if it had been extruded. I have sanded it down with a 600 grit paper and it is now much flatter. So far I haven't noticed the from-sleep-resistance-drop, although I'll need to test with a variety of different attys over a couple of days.

[dwcraig1]

0.00138 is not going to work with CW 430, try around 0.0019 - 0.002

[Wayneo]

dl12345 said:

I tried some 430 but didn't get very good results as the steam-engine profile didn't seem to match the material. I got mine from Crazy Wire Company. Where do you source yours? I'd like to give it a try again as I get better results with SS304 than with SS316L, so the improvement should be even more marked with SS430

I got mine from unkamen. 28g. I find it very springy, so I always straighten it with a drill, then make a 3 simple twisted spaced coil. I believe I just used the djlsbvapes TCR (SS430: 0.00138) for the 'material'. 

[dl12345]

dwcraig1 said:

0.00138 is not going to work with CW 430, try around 0.0019 - 0.002

Correct, it doesn't. But then surely this implies that CW 430 isn't really 430 but something else instead?

[dwcraig1]

Just because Steamengine doesn't list it doesn't mean it's not SS430. Pretty much just my opinion though.

[dl12345]

dwcraig1 said:

Just because Steamengine doesn't list it doesn't mean it's not SS430. Pretty much just my opinion though.

Granted, they're a good vendor. I doubt they're labelling something as SS430 when it's not. Looking at this link I see they've now started listing the composition of the alloy. It's not nickel free....

[dwcraig1]

I bought some 430 from CW, works just fine for me. I made some Claptons with it, 2 strands of 25 gauge CW 430 wrapped with 34 gauge Kanthal dual coil build in a Velosity

[dl12345]

dl12345 said:

I noticed in the last day that when my 75 goes to sleep and wakes up, it resets the resistance as if I am putting in a new coil. For some reason, when doing this (as opposed to having a new coil put in while the device is awake), it appears to consistently under-read the ohms. It only does this when going from a sleep state - my two DNA200s and ohm reader show the same ohm readings, as does the 75 when I put the atty in when the board is awake. If I then take out the atty, reset the resistance with a much higher or lower ohm coil and then put it back in, it reads the original resistance, not the lower value that it did from sleep state. Since the difference amounts to about 0.01 ohm, this would certainly cause a weaker vape. 

I noticed this post from FairCold and have done the same now to my VT75 nano, as it also had a slightly uneven 510 connector pad - almost as if it had been extruded. I have sanded it down with a 600 grit paper and it is now much flatter. So far I haven't noticed the from-sleep-resistance-drop, although I'll need to test with a variety of different attys over a couple of days.

So I now confirm that my problem seems to have largely resolved itself after doing this fix. Flattening and smoothing down the 510 nub on the connector appears to have stabilised the resistance readings and the temperatures with my 75 are much closer to my 200s when using the same atty, presumably because it's reading the resistance more accurately due to a superior contact surface.