Semi-Repost ePipe mod

[Dave Rickey]

Well, now that I can start my own threads, I thought I would post the progress reports on my ePipe:

Well, since I can't start my own threads, I guess I'll have to hijack yours, sorry.

Here's my prototype e-Pipe 1 week ago:



That's a CR123 under that black heatshrink, with a connector for the power at the end of the green heatshrink. the red and black wires lead to an RCA connector, which goes through a nasty hacked-together adapter to the 801 atomizer. After that picture I connected a switch, and it actually worked great, although I don't have any pictures.

Then I tore everything out, bored the bowl of the pipe wider, built a new battery pack around an 18350, shortened the stem end, and built a proper RCA-801 adapter (I also have a 901 adapter) and added lights and a safety switch. Here's what it looks like now:



Pretty much the same state of assembly, but with a lot more features and more wires. The battery pack is an 18350 with PCB added. You can't see the LED's from this angle (they face towards the user, the yellow one will light when you are vaping and the green one when you hit the button but the safety switch has been turned off. The little red can in the upper left corner is my next-generation battery pack, you can see the small gold-plated coax fitting if you squint (the bigger black patch is left over from an experiment that didn't pan out.

Materials wise, it's about $20, it took about $500 in tools to go from prototype 1 (which only needed a Dremel and hand drill. plus a little soldering and a butane torch) to 1A (which required a drill press with cross-adjustable vice, an ESD soldering station, and some really hard to find drill bits).

Well, here's the finished prototype:



That top cap is the butt end of a dead flashlight, it's way too thick because my wiring method was designed to be easy to change on the fly while I worked things out, and there's a lot of excess wire and heatshrink that has nowhere else to go.

Notice the amber LED, that tells you it's operational (actually sending power to the RCA fitting:



If the safety switch is engaged, triggering the button lights a green LED and no power goes to the RCA fitting:



And here's the basis of the next model:



I won't need to run wires outside the bowl except for the battery fitting (I'm going to use strips of ribbon cable from an old black IDE cable, now that all my drives are SATA, I have a bunch laying around). The top will be capped off with a rubber pad and a large brass washer, I'll be putting the switch on the side under the index finger instead of under the thumb. The combination will let me reduce my form factor for the cap to around 1/4 of an inch (rather than the full inch it is now).

The battery pack you see there is a keychain pill bottle with the fob portion removed, this one is red because that's what I had lying around, future versions will be silver (cheaper and better looking), black if I can find a paint that will stick reliably. I'll use a single LED for status, red for safe mode and green or amber for operational. I don't like the way the safety switch I used looks, so much so I didn't even take a picture from an angle that would show it. I'll keep the switch in the design, but come up with something much more polished. Functionally the prototype is great, I vaped all day (2ml worth or so) and used only half the battery capacity. I'll need to make a custom charger, as making the battery removable independently complicated assembly too much, I don't want a potentially unprotected cell feeding this, and it loses the idiot-proof functionality of the connector.

Even as an ugly hacked-together prototype, this would do better on the "would you want to take this through airport security" test than the sonic screwdriver, pipe bomb, and battery case mods that are the standard these days. The new model will be much sleeker and polished, and it will keep the significant features; safety switch, indicator light, large 1200mAh battery, and a safety vent for the cell that points the positive end down). If the battery goes into thermal runaway and started venting, a little plug of hot glue will get popped out and release the pressure (otherwise, what I've got there isn't a battery pack as much as a small incendiary grenade, even with a protection PCB).

I'm mostly finished with the second prototype, here's the mockup mechanical assembly:



The switches and battery case are all standins for the planned versions, which will be roughly the same size but less clunky (the safety switch will be a black rocker the same size as that mini-toggle, the main button will stop at the top of where the washer does now, and the battery case will be black plastic rather than red aluminum).

The rubber grommet will be pretty much the same, and a flat black metal disk will cover that (total height 1/4-3/8", versus the full inch of the first prototype). It's hard to tell from the cheap cell phone pictures, but this pipe is a much higher quality than the other, being made from briar and having a more complex texture to the exterior. It has a straight stem, which is easier to work with for prototyping purposes, but I'll probably switch back to bent stems or offer an option, as bent stem pipes feel more natural to me.

Also still fiddling with switch position, non pipe smokers will probably find the side position fine, but some of them may prefer it to be towards the back under the thumb rather than on the side under the index finger, and there's also the issue of left vs. right-handed users (not as much of a concern with the top switch). When I have a plastic battery pack casing, I'll see if I can compress things enough to make room under the metal disk for the button (which will be only 8mm for the main casing).

Being able to fit this into a standard pipe is pretty difficult, there are some jumbo pipes it would be far easier to manage it in, but I want something that looks to first glance like an ordinary pipe without standing out for size or materials. I'm very tempted to switch to protected 16340 cells, simply because it's making room for a protection PCB that makes the 18350 so damned hard to wedge in there vertically. I'm trying to find a source for a protected 18350, or at least the bits that make 18500's and 18650's protected, without ripping them out of functional cells.

--Dave

[Robert]

Very Nice work Dude- I'm now scrapping my pipe idea- no I still want to make it but yours is outstanding- Big Props

running lights- nice!

[SmokinScott]

Cool project; thanks for the pics and keep us posted.

[Dave Rickey]

Well, the second prototype is almost complete, the parts I need for final assembly won't arrive for at least a week, so I figured I'd update this again now.

It's all assembled, pretty much as planned except I gave up complete on the aluminum pill bottles as battery cases (the protection PCB operates by interrupting the ground, and you can't do that reliably when the battery is entirely surrounded by metal). This one is back to heat-shrink and electrical tape until I get the tubing I need for proper battery packs. Mostly that means the battery connection isn't quite as neat and clean as it should be, but functionally little changes.





As you can see, it looks like a pipe as long as you don't see the battery connection. I used a silver 801 just so it would be more obvious I had actually done something.



I have fairly big hands, but you can see that it's a pretty standard sized pipe, a Billiard style which is one of the vertically taller of the traditional pipe designs, but not particularly noteworthy for size.



A rough mockup of what it will look like once it's properly assembled, that switch will be replaced with something flatter and all black, the neoprene washer on top will be replace with a metal (but still black) disk, and that will be held in place by 3 black screws in slots, press and turn to release.



Safe mode now lights up in red. If you look carefully, you can see the mini-toggle in the down position.



Operation mode is now green. Note that it's green even though there is no actual load (atomizer isn't attached), that's something I hope to fix in the future. There's only one LED, which is supposed to be able to do red, green, or amber, but I can't get amber out of it without running so much current the LED starts to overheat. I'll keep looking for a better solution there.

I'm pretty happy with this prototype, the main goal I had for it (getting all the wiring except the battery connection inside the pipe) has been accomplished. I'm trying to decide if I want to commit to ordering materials for a truly polished version, and weighing the different options for actual pipes to use for shells. It's actually hard to find a real wood pipe that doesn't cost too much to be hacked and butchered this way, yet has a consistent quality and physical spec between units. Lane and Dr. Grabow are the leading contenders, although there's some Bent Bobs I *really* like for only a few dollars more.

--Dave

[rbonie]

Well, the second prototype is almost complete, the parts I need for final assembly won't arrive for at least a week, so I figured I'd update this again now.

It's all assembled, pretty much as planned except I gave up complete on the aluminum pill bottles as battery cases (the protection PCB operates by interrupting the ground, and you can't do that reliably when the battery is entirely surrounded by metal). This one is back to heat-shrink and electrical tape until I get the tubing I need for proper battery packs. Mostly that means the battery connection isn't quite as neat and clean as it should be, but functionally little changes.





As you can see, it looks like a pipe as long as you don't see the battery connection. I used a silver 801 just so it would be more obvious I had actually done something.



I have fairly big hands, but you can see that it's a pretty standard sized pipe, a Billiard style which is one of the vertically taller of the traditional pipe designs, but not particularly noteworthy for size.



A rough mockup of what it will look like once it's properly assembled, that switch will be replaced with something flatter and all black, the neoprene washer on top will be replace with a metal (but still black) disk, and that will be held in place by 3 black screws in slots, press and turn to release.



Safe mode now lights up in red. If you look carefully, you can see the mini-toggle in the down position.



Operation mode is now green. Note that it's green even though there is no actual load (atomizer isn't attached), that's something I hope to fix in the future. There's only one LED, which is supposed to be able to do red, green, or amber, but I can't get amber out of it without running so much current the LED starts to overheat. I'll keep looking for a better solution there.

I'm pretty happy with this prototype, the main goal I had for it (getting all the wiring except the battery connection inside the pipe) has been accomplished. I'm trying to decide if I want to commit to ordering materials for a truly polished version, and weighing the different options for actual pipes to use for shells. It's actually hard to find a real wood pipe that doesn't cost too much to be hacked and butchered this way, yet has a consistent quality and physical spec between units. Lane and Dr. Grabow are the leading contenders, although there's some Bent Bobs I *really* like for only a few dollars more.

--Dave

Great look Dave... Been thinking about a pipe mod... lots of good stuff. Thanks

[Dave Rickey]

Great look Dave... Been thinking about a pipe mod... lots of good stuff. Thanks

I'm going ahead with the next stage of the project, I've got a friend who is an electronics engineer designing a PCB for power regulation and switching, and I'm ordering a whole bunch of components so I can make a decent number of them.

I'm going to be using acrylic tubing and plate for the battery casing (US Plastics). I'm getting a bunch of the same PCB's used for 18500/18650 protected cells (DX), and some of the same kind of ultra thin wall PVC heat shrink used by the battery manufacturers (Cell Pack Solutions) so I can make something equivalent to an 18350 protected cell (which isn't available from *anyone*, although I'm exploring the costs of having a batch of custom cells made). I've got three options for switches, two involve using the central module of what is normally a larger switch, without the housing, and putting a rubber cap designed for flashlight switches over that to make it pretty (DX again), those two involve ordering directly from the factory which means MOQ kicks in (as it does for my aluminum disk for the caps). I've dodged MOQ as much as I can on most of this (that heat shrink, for example, is normally only available in rolls of 500 feet or more and that's the *only* source for small quantities I've found), but some things there's just no way around it.

My wiring plan is getting more simplified, I should be able to set things up so I have only one solder connection (essentially my ground plane) inside the pipe itself (will make things look better and assembly go faster). I'm exploring various options for power regulation, so that vaping quality doesn't float with cell condition and the resistance of the atomizers, there's a couple of off-the-shelf solutions for that as well as that custom PCB (which will do other things as well).

I'm considering moving *all* of the electronics up into the cap assembly, as that will be where the PCB has to go (cooling requirements make anything else too complicated) and it would mean less fiddly Dremel work. That would mean the cap assembly would no longer be completely removable, and might wind up a millimeter or two higher in profile, but would make assembly a lot faster and less error-prone (Briar is notoriously hard to work with machine tools, and virtually all decent traditional pipes are made from either that, or the even harder to work Meerschaum stone). Even if not, everything is going to get moved to the stem side of the bowl because the wood is usually slightly thicker there and putting the main switch on that central line in back will be the most comfortable and convenient for users (anywhere but there or the cap assembly is too awkward to switch hands on).

The hardest part of the whole process is drilling the pipe out to actually have enough room for the battery. I've got a drill press I can't use for anything else now because of the modifications I made to it so I wouldn't blow up the pipes, and I'm having to buy a second one for regular drilling. I'm also having to get a bandsaw for cutting the tubing, and I'm *really* tempted to buy a small machine lathe (but at $500, I'm resisting the temptation). If I used a tiny little cell like a 10280, I could probably skip drilling the pipe, but then I'd have less than 1/3 the actual power duration (not much better than a stock 801, just in a pipe).

Power regulation and the other advanced electronic functions complicate things and add a lot of expense, so I'm probably going to have two models; A basic pipe that replicates what I've done in the current prototypes (but with a better aesthetic), and a premium model that adds those other functions but costs a lot more. I should have early examples of the basic pipe in a few weeks, until all the materials come in I can't produce anything that looks much better than that second prototype. Both will use the RCA power connection to the atomizers.

--Dave

[Some Guy]

Somehow I like the idea of putting your finger in the bowl of a pipe to turn it on.Would be great in public.lol.Too bad you moved on from there.

Have you looked at Small parts for heatshrink? I bought some recently and they seem to have a large selection.
Heat-shrink Tubing- SmallParts.com

[Tecratk]

I love it! I'm not very educated when it comes to different types of batteries and what voltages they have. How much voltage will the battery that you're running in this produce? 3.7 or 5v/6v? Also, did I read correctly in that you're basically building the battery into the device? So you won't be able to pop it out and put in a new one?

[Dave Rickey]

Originally I was thinking I'd build battery packs and you'd pop those in and out (because I couldn't find a battery housing that would hold an 18350 and fit inside the pipe). I've worked out a way to have a proper battery compartment, so you'll be able to just pop the cell itself in and out (cheaper than a battery pack).

The basic pipe will run straight off the cell, so your normal Li-Ion range (4.2V on a fresh cell, down to 3.0V when it hits the undervoltage limit, but with less voltage drop than anything but 18500/18650 based mods so a fresh cell stays high -temp longer). I'm currently researching a booster circuit based design that will let you run at a stabilized equivalent of 3.6V or 4.5V (switchable), but it adds so much expense it will be an entirely different model.

The 18350 seems to hit a sweet spot on duration, I can vape for 2 days (about 5-6ml worth) on one charge, probably because it's not straining to provide the current needed the way a slightly smaller cell does. Battery duration is tied to rate of discharge compared to capacity, as well as explicit capacity. If you're draining a full amp from a smaller cell, it's going to provide fewer mAh than it would at a lower rate, and an 18350 is just barely big enough to handle eCigs without cutting battery life. Should probably be able to get a lot more charge cycles from a cell for the same reason.

I tried 16340's because they can be purchased as protected cells, but even though they were nominally rated only 25% lower, they provided less than half as much actual vaping.

--Dave

[Dave Rickey]

Quick update: Parts are on the way, some will be delayed, apparently because China is closed until the 5th. Picked up a bagful of the model of pipe I settled on for the shell of the initial production version (trying to forget how much that cost):



I need to get a better camera, and buy/build a light box. Anyway, I went back to a bent pipe, I just like them better and they'll be a little easier to work with. As stuff comes in I'll rebuild the second prototype, then build a third to the new plan. Assuming that works out, then I'll start offering them for sale.

So many things I've got to take care of now. I need to incorporate, get an EIN and register with the state so I can stop paying sales tax (instead I get to collect it, oh joy). Naming the initial model the Andalusian, for the province of Spain where the cigarette was invented.

--Dave