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DIY Bulli Vaporizer

Discussion in 'DIY' started by Pipes, May 16, 2012.

  1. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    A quick add on to my above post:
    I have started using the one piece ego drip tip. I like the one piece because it's easier to remove while unit still hot. The two piece wants to separate at the 510 tip. Save some coin as well. Many out there, just google "ego drip tip type b".
    Also, the single coil element IMO is the way to go. 30 AWG Kanthal type A. For 6 volt 3 ohms or 4.5 inches seems good.

    NEW CHEAP ALTERNATIVE:

    I was searching around the web and found China has started making Bulli Clones and caught my eye.
    The main thing which really got my interest was the price. Under $5 a unit with the catch being minimum quantities. I would imagine soon to be available in local ecig shops.

    [​IMG]
    [​IMG]

    Well had to take check them out. I ordered a test sample pack to experiment with.
    They come pre-coiled with a 3.5 ohm element. The center plate with puncher pin un-screws rather than pressure fit.
    The size of that puncher pin is crazy. The tank does not come with a cap. I thought that was odd as is the only thing missing besides the ejuice and battery to get it up and going for ejuice users.

    Right away I ran into a noticeable problem.
    [​IMG]

    The skirt is not removeable. Dam, I thought it was as I discovered there are more than one type of clone. Anyway, have to work with what I got.
    My first impression was that these things are cheap, cheap, cheaply made. Material is that brassy looking stuff and is brittle as hell. At least this made it easy to break away that skirt. Now as for the actually design, I have to admit it's very clever how they put it together. Of course the first thing I did was sacrifice a unit to see how it's put together.

    [​IMG]
    [​IMG]

    A big electrical difference is the center pin of the 510 connector is threaded into a circular plate which has the positive post mounted on it. This is the complete positive side of the circuit. The ground pin is screwed through a hole in this disc with a thin piece of silicone insulator. This is one of the weak points of the design. The method they use to attach the heating wire is using very small screws which go down the posts and press the element via small holes in the side of posts. These are very flimsy the philips head strips very easily. A proper fit screw driver is a must here. I do not think this unit would hold up well for multiple rebuilding. But for once or twice......

    Air path is also quite different. This unit draws air up through the center pin as to support automatic batteries I guess. At first I was a little disappointed as again like with the skirt I thought I saw holes in the pictures. Must have been a different clone. There is another one called the "Bully" spelled different. I think that this the one with holes and removable skirt. Anyway, the holes on the sides of the 510 threaded piece IMO were too small. I drilled them to 1/16" and seems OK. I left the single hole in the center alone.

    Unit overall mass is much less and the actual base is about 3 mm shorter with skirt removed. Causes heat differences.

    The rest of the mod is pretty much the same as with the original Bulli TM mod. The center portion screen hole part is a little smaller and threaded instead of a rim grooved like the Bulli. The juice tank piercing spike plate is removed by unscrewing it instead of popping out.

    Here is the result which is pretty much the same as the Bulli.

    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]

    So in practice it does perform much like the bulli. I did have issues with shorts from ground post shorting out to the positive power plate. This came about while prolong heat bench testing. The solution was to adjust post so had clearance and no pressure against side teflon insulator. IMO, not a permanent solution as makes too easy for short circuit. Might try making the hole larger in positive plate. ?
    The biggest issue which is very different is the heat transfer back to the power handle is much more. I noticed big time as I use my little power handles and they get too hot to use for a quick session with this unit. Can still use if wait a bit between hits. With the Bulli it gets hot but still usable.
    I have given a unit to my co-worker for testing. I am really bad at not knowing much taste differences, but he seems to.

    The Pros.
    -Cost effective

    The Cons.
    -it's very cheap material and will not last. The 510 connector will likely chip first time drop.
    -reliability issues with ground pin pass through
    -fast heat build up

    Overall opinion, Basically you get what you pay for. This clone does perform but just feels cheap and have doubts as to longevity. Time will tell.
    I will keep the testing going with this guy and keep this thread informed. IMHO, this Clone unit (UFO) is not worth pursuing at this point if thinking of ordering.

    Pipes
  2. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Have a couple updates.
    First off the Clone unit has actually been working out pretty good. I've used it a few times and works fine. The unit I gave to my co-worker, well he won't give it back til his Bulli he has now ordered comes in....guess that mean he likes it. His unit of choice has always been the IO but also owns a T1 which he rarely used. Kind of speaks for itself.
    As for the grounding post which was hunting me I did cut and file a larger opening.
    [​IMG]
    [​IMG]
    [​IMG]

    Here's a before and after:

    [​IMG]

    The holes I drilled out. 1/16"

    [​IMG]

    I still would not count this as a quality vape by no means but does work well. Just very cheaply yet cleverly made and it shows. Still transfers heat fast down the handle and needs tubing or extender if given it.

    NOW FOR ANOTHER TWIST:

    Been asked about a lower voltage winding. Well was getting around to it as seems next logical thing to do before my next battery purchase.
    Starts a new chapter.
    It seems to get a usable length of wire the resistance per inch would have to come down. In other words a thicker gauge. The thickest I have is 30 AWG so I tried a triple twisted 34 AWG. A guestimate on gauge.
    Heres the result (no ceramic)

    [​IMG]
    [​IMG]
    [​IMG]

    With some ceramic:

    [​IMG]

    Although it looks not bad in the picture, the glow was not as hot as the 6 volt one. So I scrapped it and went back to the 30 AWG. To get the need power I had to shorten to about an inch and a half which made for only 3 loops in the winding. To help compensate for the surface area I used a longer piece of ceramic.

    [​IMG]
    [​IMG]
    [​IMG]

    Notice the meter now. The 6 volt was running at about 12 watts and the numbers on the meter are 3.7 volts and 3.22 amps or yep 12 watts. Have not tried yet but suspect some success, if not I'm going to get some thicker stuff. Maybe get some 28 and 29 AWG.

    Getting interesting again.
    I will update as thing get worked out. Not in a rush but nice to know the recipe for a 4 volt device. I'm guessing a thicker gauge is needed for optimum results. Stay tuned.


    Pipes
  3. Egzoset

    Egzoset Vaporist v2.0

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    Salutations Pipes.

    You've got me thinking lately: surround it with glass, replace the air inside with some rare inert gas and it's ready to glow like the sun!

    Which sort of reminds me of halogen lamps somehow...

    :peace:
  4. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Location:
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    The bulb idea is intriguing and have had an eye open for that perfect fit of voltage, wattage and size. If you can find something suitable let me know and will give it a shot.
    OK, I have given the 4 volt coil a run and happy to say IT WORKS!!!!! (AWG 30)
    In fact, once warmed up it's pretty much the same feel as the 6 volt mod. I have taken a couple pics for comparison. Tried taking with both battery types topped off and under the same lighting and angle. This is so one can compare the overall average "glow". This is really the only tool to judge the temperature.

    [​IMG]
    6 Volt coil
    [​IMG]
    3.7 volt coil
    [​IMG]

    To do this testing I used a 18650 battery in the TV sleeve with the rear outside label removed for the ground connection.
    [​IMG]

    Only difference I could notice is it takes slightly longer to initially warm up. Maybe 2 tasty no visible vapor hits instead of 1..? After that performance is very close. So close that I have not played enough to notice the small differences. However, I thought I'd report, as it is clear this is for sure a doable recipe.
    I have also ordered some 28 AWG as I think it would be nice to get a couple more windings on that coil. Who knows, might make it better. Or worse.???

    Pretty much set for a voltage switch if need be. Did a ecig winding change as well.
    For ecig users:
    Went from AWG 34, 3.1 ohm 6 volt to => AWG 32, 2.2 ohm 3.7 volt.
    It also had pretty much the same taste and vapor as the 6 volt.

    Happy modding,
    Pipes
  5. Egzoset

    Egzoset Vaporist v2.0

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    Salutations Pipes,

    It was little more than a "flash", so to speak...

    In practical terms the presence of glass around such a battery-operated heater element would certainly take its toll i'm afraid, though i figure this might become a lesser concern should your project happen to include an AC power adapter...

    :peace:
    Pipes likes this.
  6. jambandphan03

    jambandphan03 Vapor Goddess

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    nice work pipes!! :D Keep it up!
    Pipes likes this.
  7. BiL0

    BiL0 Member

    Messages:
    1
    I was looking at the same thing (a bulb as heating element)
    http://www.solarforcestore.com/servlet/the-839/XENON-BULB-SUREFIRE-3P/Detail
    here a link for an halogen bulb at 3.7V (it uses 16340 or 18650 batteries)
    but I guess the heat won't be enough. but I may give it a go.
    the size is pretty small so could be fitted inside a rebuildable atomizer. :)

    B.
  8. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Looks like a possibility. They do not state the wattage but the fact that the reflector is aluminium is a good sign. As in, if it was just coated plastic we would know it would not be hot enough. I have my doubts as to enough heat for convection vaping but maybe if it could be arranged to use for conduction vaping? In other words if the herb could be in direct contact with the quartz the conducted heat might have better results.
    Also, pending the heat, this might be a great concentrate vaping device as the bulb would be easy to clean?? (Just thought I'd through that in) Of course more likely just make the bulb crack.

    BiL, welcome to the fun. A place to play and try different things is IMO very exciting.
    Really gratifying once you achieve a working unit for sure. Not to mention the testing can be very intensive.....:ko:
    Glad to see follow FCers getting on board here.
    :tup:
    Pipes
  9. Egzoset

    Egzoset Vaporist v2.0

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    Salutations,

    Yes, me too after i've browsed around and found some data from these web sites which started to pop up after a while:


    Then i used key-words like these for my search:

    YouTube Image: CPF ROP HotWire

    ...and BAM! It seems portable monster flashlights and vaporizers share some characteristics. There's a good sample of tabloïds on CPF showing that a low-voltage (4 Volts) 24 Watts bulb has a ridiculously short life expectancy of a hundred hours if i've read correctly!

    I'm sure the Venus guy knows a few things about halogen heat sources vs battery operation, too bad he's not around often and probably not available for parallel discussions anyway. But even if it turns out that low-voltage halogen bulbs aren't suitable in vaporizer applications i believe there's useful information to be gathered from the CPF people - who appear to have seen a lot of exploded cells by the way!...

    Hummm... There's got to be some figures about power conversion efficiency somewhere. It would help to know how diverse sources of heat operating on batteries would compare! For example i've read somewhere that it's about 88 % for induction, so i'd be curious to see all the numbers alligned side by side.

    :peace:
    Pipes likes this.
  10. Trever

    Trever Well-Known Member

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    Just noticed this little beast of a thread pipes! Boy your a busy boy scout ;) Impressive indeed keep tinkering!
    Pipes likes this.
  11. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Thanks Trev, I do love to tinker.
    I received my AWG 28 Kanthal today and re-build the 3.7 Volt unit. I will be testing later tonight.
    Took a couple pictures but forgive the focus, kind of rushing it.
    With the thicker wire I was able to get 5 loops rather then only 3 to achieve to same 12 watt power.
    1.2 ohm seems to be the number that works for this. The lenght difference was around 1/3 of an inch longer then the AWG 30.
    AWG 30 - .9" = 1.2 ohm
    AWG 28 - 1.25" = 1.2 ohm
    [​IMG][​IMG]

    Now, a point of interest here is where the wire begins to get red hot. In the earlier 3 loop winding the wire was red right from the connection point. This indicates I was pushing the element right to the limit of saturation and IMO should be avoided if possible..??? We'll see. Now in this latest coil with 5 loops the first loop on either side is much less hot then the center 3 loops. To me, this indicates driving the unit much lower then it could achieve. A good thing?? Maybe??

    I will post back once a real life test is performed.

    Just a footnote. This thicker gage wire is so much easier to work with that it now is making more and more sense to go lower voltage. Initially was to save on batteries. Now finding other benefits. Bonus.

    Pipes
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  12. jambandphan03

    jambandphan03 Vapor Goddess

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    loving your results so far Pipes...
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  13. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    I am too Jam. :ko:
    Gave the unit a good drive. Performance was much like the 3 looper but a little cooler with slightly less clouds. But not wimpy neither. This can tweaked by taking a mm or so from the winding. Note many would probably like it like this as absolutely seems no chance to combust.

    Comparing the 6 volt to the 3.7 volt winding is going to take a bit of tweaking. I had the 6 volt right where I liked it. So far it looks like with some adjustments the 3.7 volt might come very close. The only real difference I found so far, but might be in my head, is the warm up seems longer with the 3.7 volt but performs very closely after that. Now in looking at the element it seems to get hot just as fast and holds the heat just as well.
    The benefits are been able to use 18650 batteries which are generally cheaper and easier to get then the 3 volt cells. Myself have many sitting around. E-cigs taste better at lower voltage. (IMO) And lastly since this is a re-buildable unit, the thicker resistive wire associated with lower voltage makes for easier maintenance. And in my case experimenting.

    Will keep thread updated.
    Pipes
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  14. jambandphan03

    jambandphan03 Vapor Goddess

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    I like the single 3.7v cell too. Seems to be the best bang for the buck, if you can get it all to balance out. Keep it up!
    Pipes likes this.
  15. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Well, I have to call the 3.7 Volt a success. I took about 2 mm off the length of the coil (1 mm at a time) and it now measures just under 1.1 ohm. It was just over 1.2 ohm before. The performance is very good. Not huge clouds like the 6 volt but very consistent and easy to control. Have not taken any more pictures as its much the same but windings slightly tighter. The glow of the two end loops is a little brighter indicating closer to saturation but still room to crank it up some more if I so feel inclined.

    For a re-cap of recipes:
    6 volt- AWG 32@ 2.5 - 3 ohms pending personal preference.
    3.7 volt- AWG 28@ 1 - 1.2 ohms pending personal preference.

    2 for 2 with the Bulli. :clap:

    Should I go for 3?
    Here's a hint. I ordered some of this tonight.

    [​IMG]

    Now WTF can that be for? Got the Omegabond 400. Another hint lyes in the first couple posts of this thread. :brow:

    Pipes
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  16. Egzoset

    Egzoset Vaporist v2.0

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    Hello there!

    I have a question, maybe you know the answer. :hmm:

    What's the power requirement in comparison to levels currently supported in the market?

    :peace:
  17. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    The power requirement is actually very modest in comparison. Keeping the current down under 3.5 amps makes it workable for mid price ranged VV mods. Older VV mods like the original lava tube cut out at around 2.5 amps which will work for the 6 volt Bulli. I think there are some that support over 4?? I prefer direct switch power handles myself which is why I love my TV handle. I have a Bolt on order with a simple horn switch to run the 18650s.
    Comparing to convection devices I've checked out this is very power efficient. A simple way to compare is by the wattage, this unit seems to run well at 12 or so watts.
    T1 advertised 30 watts.
    Original EVO was 20 watts.

    Hope this helps,
    Pipes
  18. Egzoset

    Egzoset Vaporist v2.0

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    It helps.

    So, if the practical maximum power level is about 30 Watts and conversion efficiency is a mere 50 % then this still would generate 15 Watts while you can manage with just 12... I'd be curious to see how conservative 50 % happens to be when it comes to building low-voltage switching-mode converters.
  19. Egzoset

    Egzoset Vaporist v2.0

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    Salutations Pipes,

    Hummm... How was this suposed to fit into the overall picture? I myself can't remember anymore, sorry!

    :doh:

    Well, there's always the matter of power-handling contacts on my mind - that must be how the thought of power converters came to me i guess... So, i wonder. Won't the rush of current possibly leach metal from the contact points and hence end up destroying them ultimately?

    :peace:
  20. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    I'm not quite share what your after here. Most decent available power handles which are currently used for ecigs will work fine here. In fact I just received my Bolt handle I had ordered and is working great. As for contact erosion goes, well I guess, but would this not be the case with all such devices. :shrug:

    I have been having fun playing with the ceramic mix I got. Just familiarizing myself so far but some fun stuff.
    Finding it is like working with wet sand. Like when you were a kid and playing in the sand and you start dripping the wet sand slowly on top of itself, and it stays put. Until you add that little too much and it all falls down. Much like that. Takes a full day to dry so you can sand (or add some more). Embedding the resistive wire has some learning curve as well. Some interesting stuff and will post pictures once I get a bit further.

    Pipes
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  21. Egzoset

    Egzoset Vaporist v2.0

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    Hi,

    Only this: i realized an appology might be in order while i was re-reading myself!

    ;)

    Exactly, with "all such devices" and this happens to be the very part i shouldn't have overlooked when i wrote my previous comment on switching-mode circuitry... In the context of a mechanical power switch there's no room for "Solid-State"/"Silicon-Based" features, or at least those would fall outside the scope of your action anyway.

    :peace:
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  22. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Well I have played and made a couple experiments with basic ideas and platforms. Not completely sure where this is going but the ride is fun. Here's some pics of what kind of stuff I've been toying with.

    [​IMG]

    Found it has an expiry date which was not expected.

    [​IMG]

    Bits and pieces.

    [​IMG]
    [​IMG]

    Testing under some heat. Seems to hold up. Left on for an hour.

    [​IMG]

    Used a piece of paper to make 1/2 cylinder and tack on heater wire.

    [​IMG]
    [​IMG]

    Some other embedded elements.

    [​IMG]
    [​IMG]
    [​IMG]

    Thinking of using IC mounting pins to make a pressure fit mount for the element. This would allow for the element to be pushed in from above the first Bulli cylinder (where I have been installing the screen.) The cylinder would then support the ceramic "cooker bowl". Possibly a second mid section could be added to enclosed the whole bowl, if addition support is needed.

    [​IMG]

    Cooking the cooker.

    [​IMG]
    [​IMG]
    [​IMG]

    I am also trying to embed the actual element recipe known to work for herbal. (1 ohm) I have attached normal hook up wire to the ends of the element wire so the length of element is 100% used. This gives me 2 more loops as well as keeps some heat away from the Bulli connectors. Might be worth while for all the mods with the high temperatures we're working with. I simply wrapped the wire around the element (slowly as the element wants to bend first) and gave it a pinch with pliers. Then wrapped the element around the hook up wire on the other side. Have been meaning to google a proper way as I'm sure there is a better knot. Never got that badge in boy scouts neither. :(

    [​IMG]

    Trying a couple sizes of loops.

    [​IMG]

    I have since dipped those coils in the ceramic and are at my work curing away. That will be my next step. Replacing one of my working units with one of these and see if any different. Honestly, I expecting little change to more likely less heat. Hoping to be able to increase draw speed and have less cool down. I plan to chip away some ceramic to expose the element as it seems not to glow while actually embedded. More fun.

    So this is getting interesting and I welcome any ideas on how to use it.

    :smug:

    I have also now made a new jig for testing and such. A very simple modular design. Just using the banana test lead jacks and a cheap magnifier glass holding base. Note the little 510 connector with the IC pin connectors mounted. This simulates what I have in mind to modify the Bulli connections.

    [​IMG]

    The red plug is for power input. Either 5.5 mm or 510 power handle. Gets me away from alligator clips and possible reversing polarity killing my little volt meter. (has happened) :doh: One black is for the 510 device and one is the voltmeter. Still need to find a simple ohm meter.

    [​IMG]

    Happy modding,
    Pipes
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  23. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    Here's a general update.
    I have found the ceramic I bought is not really great for the job in using for the replacement of the ceramic which I have been using. Problem seems to be the heat transfer density must not be good for this. It has uses but mainly for securing purposes. Oh well, can't win them all.

    An observation I have made is the thicker the gauge of the wire the more the resistance changes after some heat up and cool down cycles. Much more noticeable then thinner gauges. When using AWG 28-29 I found you need to start with .8 ohm to end up with a 1.1 ohm element. This made it a bit confusing til I figured out what was happening. My experiments would work for a session or two and then seem to not be hot enough. duh.....

    I have also started to use connector pins on the ends of the pre-measured resistive wire.

    [​IMG]

    I snip the crimping part off leaving just the post part. This post is hollow and the wire fits down the center. I have been pushing it in the full length and squeeze the last 1/4" or so. Bend it 90 degrees and it's ready for insertion under the screw. Really makes a big difference in ease of installation under the screws. Also, takes the guess work out of the length. Another note that now working with shorter lengths, a small difference makes a much bigger difference performance wise then longer lengths.

    Here are a couple of the failures I had for your entertainment.

    The first one I tried embedding only half the winding in the ceramic. Looked good. Long warm up, small clouds, feels hot on lips, combustion sneaks into the picture without warning. :hmm:

    [​IMG][​IMG]

    Moving on I decided the ceramic must be to blame...?

    Now this one actually never even got to the trial stage. Felt it was not robust enough for my liking. Looks interesting though.

    [​IMG][​IMG][​IMG]

    This last one really had my hopes up. I used the outer casing from a power resister. Used a hammer to break it up and filed out a chunk to do my bidding. My thinking was to have more vertically oriented element for longer air contact. Made sense in my head anyway. It actually wasn't too bad but heat up time seemed slow and again that dam combustion would sneak up on you. I don't mind if a unit is capable of combustng but you need some predictability. Not, wisp, wisp, bang. Yuck.

    [​IMG][​IMG][​IMG]

    Might revisit this design down the road.

    I have currently back to the original AWG 28 cut to .8 ohm and cycled til 1.1 ohm wrapped around the ceramic cut from the aquarium filter ceramic. Keeping an eye open for this key element.
    Seems that the working power is from 16 watts down to 12 watts for this unit to give good results with the ceramic I have tried thus far. My gut keeps telling me there is a more efficient material out there.
    I would love to get it down to 10 watts. Reason being that mid priced batteries have a hard time over 3 amps loads. Work, but on the cusp IMO. My cheap 18650s drop down to 3.5 volts under 1.1 ohm load where as I have one good (higher priced) battery and it stays around 3.65 volts. Also, commercially available VV handles are sitting right in this range. Expensive ones boost 4 amps.?

    So that's it for now. Suggestions for easily found ceramic pieces most welcome.

    Oh, the only other little trouble I have and just keep re-fitting is the screen. I currently form into a dome and it holds itself in place in the groove of the mid section. It does come out from time to time and I find in my ABV. Found a good gauge is the tea stainer mesh but the sides do fray. A pre-edged screen with the dome already there and pressure fit into the groove would be ideal. I can visualize in my head and I'm sure I've seen such an animal but can't remember where.

    Cheers,
    Pipes
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  24. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

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    So I posted the failures and thought I'd post a step by step of the currently working coil winding I'm using. This recipe will give a unit which runs at 14 watts with a 3.7 volt mid quality battery and stay usable until the battery depletes down below 12 watts or around 3.4 volts.
    I start with a 2" piece of AWG 29 Kanthal of which 1 1/2 " will be the active portion. 1/4" of each end is used for crimping into the connector pins.

    [​IMG] [​IMG] [​IMG]

    Pushed the wire all the way into the pin and crimped it flat. This is also the height adjustment. I made a 4 turn coil as shown. Note, that I have tried more smaller coils as well as larger coils but there really seems to be little difference as for end result. I like the 4 turn mainly for ease of making it. Bend the flat portion 90 degrees. Again, this is the finial main height adjustment.
    Proceed to mount the element. I found it best to use fine pliers to grab from sides and hold all in place while tightening the mounting screws. Insert the ceramic heat retainer and adjust coils to hold it and evenly distribute the heat.

    [​IMG] [​IMG]
    [​IMG] [​IMG]

    Here is a side view of the installation. Note, how this design improves how much heat is transferred back down the mounting posts. This should lessen the heat going back down the connection posts being healthier for the base unit.

    [​IMG]

    Now let's talk a bit about why the power levels are important. I am finding there is really big differences between batteries and performance. Here are the findings from what I have tried. I have one good (not great) 18650 protected cell and many cheap 18650 cells from ....where ever. So my goal is a device that the cheapos can still be used.
    So to mimic a really crappy battery I set my power supply to limit at 3.8 amps. This makes the device voltage drop to where 3.8 amps are outputted from the supply. This also shows how it’s a very fine line as to the coil resistance and where a battery just drops off in output.

    This is the voltage before and after break in measuring .9 ohms and then 1.1 ohm. The device voltage is 3.38 volts making the power at 3.38 v X 3.8 A = 12.8 Watts. After break in the voltage went to the adjusted voltage of 3.7 volts as the current had dropped to under the 3.8 amp limit to 3.75. Therefore, after break-in the power went to 3.7 v X 3.75 A = 13.875 Watts (no pic) without kicking in the limiter circuit. (key point)

    [​IMG] [​IMG]
    After break-In: [​IMG]

    A big variable involved while trying to hit that sweet spot is the fact the resistance changes after an initial break-in period. As I stated above start resistance was .9 ohm but works its way up to 1.1 ohm after multiple hot/cold cycles. I found it takes upwards of like 20 cycles of hot to cold before the power and voltage become stable.

    Here are pictures of comparing how a cheap battery (batt1) responds to the small resistance change as well as a mid quality battery (batt2). Very interesting findings and explains why people have battery performance troubles.

    Batt1 Before Break-In[​IMG] Half way through break-in: [​IMG] And After Break-In: [​IMG]

    Batt2 Before Break-In: [​IMG] Half way Through break-in: [​IMG] After break-in: [​IMG]

    Right away the cheapo (Batt1) is having a hard time. BTW, these batteries had been partially used to get rid of the "hot off charger" effect.
    The point here is showing just how critical having the battery load is to accomplish the best output for a given battery condition (quality). It just so happens to be on the cusp of what is needed for our purpose. Of course using great batteries will yield great results and likely run much longer.
    What is important from a design perspective is the fact that I have been using this with external power for the most part and therefore this whole exercise is easily compensated for by varying the supply. But having it perform well with "average" batteries is IMO, very important and if a device can be designed that way, why not? We are really sitting on the cusp for this mandate and I'm still convinced a major ingredient lies in the heat transfer material. (ceramic/glass/???)

    Please excuse some of the numbers may be skewed do to some come from measurement and some from calculations as well as other hidden variables. But the main idea is quite sound and of course functionality is the main goal.

    I am putting together a video set for a step by step guide and will post before long.

    Pipes

    Pipes
    Tweek likes this.
  25. Pipes

    Pipes The guy with the Afterthoughts Accessory Maker

    Messages:
    1,133
    Location:
    Up there... some where...
    Here is a post in regard to a mishap I had with one of my Bullis and found out it was easily repairable. What happened was my pliers slipped and the positive terminal post twisted. It had lost it's contact to the bottom center 510 pin. I proceeded to pull the terminal out of the base and sure enough there was no wire attached. I then pulled the center pin out of the 510 connector and it came out with the wire attached.

    [​IMG][​IMG]

    The inside of the base looked to be filled with silicone of something. Gross for sure. So I took a piece of wire looped and pushed it up through the base and pulled the wire back into place.

    [​IMG][​IMG]

    From there it was simple to re-solder it and push back into place. I pushed a mm at a time and pulled the bottom pin a bit to keep the wire from binding up preventing the post from going in smoothly.

    All works fine again and now know more about how it is made.

    In case the 510 connector ever dents or breaks, I think it could be replace without sending back to Germany.
    Worse case would be drill out and install a new connector this same way.

    Pipes
    Egzoset likes this.

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