The Bud Toaster - (currently: Model 14, version 3)

[Hippie Dickie]

villekille - thanks for sharing information about your design. Your heating to temp in 2 minutes is better than most vapes on the market. i restrict the current flow but still hit vape temp in 40 seconds.

If you do a Google on "LiFePO4 charger" you'll find what you're looking for (among the 1.2million+ hits).

this one might work for you

i haven't looked into the Microchip MCP73113 other than to see the 1A charging rate which is too low to be stoner friendly. Other chargers go from 10A to the 2A wall wart i most recently found, with prices from $100, several in the $50 range (6A to 8A), one at $25 (4A) and down to the $10 for the 2A i'm evaluating now.

These chargers mostly are for R/C people and require 12vdc input (car battery) -- not too convenient to have to strap the charger to a AC to 12vDC power supply.

Have you checked out www.alibaba.com? -- this is the business-to-business website for all Chinese factories. You have to buy in large lots, but the price is the lowest -- maybe the quality is too. i keep searching for an OEM thermometer module with no luck to date.

i wanted to have the batteries in the vape body also, but the weight of these 26650 cells is too much to hold comfortably. i'm sure this will change in the next year.

 

[vap999]

On the other hand, I have to admit that when I put a metal screen made from thin brass on the heating element, which warms up to about 350+ degrees celcius, there is some smoke forming and the colour of the mesh changes..so it is true that in hot temperatures metals react.

Clean, shiny metal surface color changes after heating to vaporizer-range temperatures are almost certainly just surface oxidation. This is a good!. Surface layer metal oxides (inert, non-reactive since already reacted with oxygen) stabilize the metal below against further corrosion, oxidation, etc. And the surface oxides presumably have an even higher vaporization temperature than the pure metal.

With copper (presumably, including brass), aluminum and many other, if not most, metals this oxidation layer is protective and prevents the inherently more reactive pure metal below from exposure to air/oxygen, water, etc. For example, the dark, even black, insoluble oxide layer that forms on copper, such as if you examine a the inside of a used copper water pipe, is what makes the copper pipe last many decades and makes it impermeable, non-reactive, non-toxic and fully resistant to dissolution despite its inherently perpetually wet environment, which is orders of magnitude more corrosive, reactive, etc. than the wimpy warm (regular oven) temperatures encountered with vaporizers. Depending on the alloy and conditions, you are probably not going to see visible oxidation on stainless steel, chrome-plated steel, etc. at vaporization temperatures (but it is probably there).

Also, the vaporization (smoke) you saw from your heated screen may partially be organic hydrides evaporating (desorbing, becoming unbound) from the metal surface. I recall reading that the characteristic smells of metals being heated are due to hydrides release, with these very much increased by the presence of body oils adsorbed into the metal surface (someone having touched the metal). And metal surfaces probably also have water vapor adsorbed in their surface, which may slightly contribute to the "smoke" upon first heating.

So, as is probably good practice with any new heated metal parts-containing vaporizer, when you first get it (or if you built it, after its completion), heat it up as hot as settings allow and let its internal parts oxidize, any oils used in machining evaporate, etc., maybe blow air through it a few times while its at its hottest, before first actually using it.

 

[Hippie Dickie]

... as the late great Billy Ray used to say, "there are no easy jobs" ...

so, in just barely less time than i can walk to Gujarat, the glassware shows up on my doorstep -- about 30 kg, 24" x 24" x 18" -- would have been a pain to carry back from India.

And so now i'm learning about dimensional accuracy in the glassware business -- that there isn't any, at least not yet from India. Maybe i should have gone to China.

Really, i guess i need to learn about glassware manufactury and what dimensional accuracy and consistency i can expect. Evidently just watching the Discovery Channel "How It's Made" wasn't adequate to the task.

@vap999 -- good post -- i appreciate the explanation.

 

[Hippie Dickie]

... working out the details ...

So the glass foundary in India stamped their logo on all three pieces (times 1000), and at first i thought how cute, i should get my own logo stamped on the tubes. Then it hit me like a ton of bricks -- WTF!!! That is, when the glassware gets hot, the binders and chemicals in the ink are going to outgas like crazy. And from the quick search i did, there's some nasty binders in the ink that is most likely used.

So, after a few emails, i've gotten an acceptable quote for much tighter tolerance (40% of this first order are unusable) and with no fucking logo printed on the glass.

It's always something. I feel ya, Mr Stone Monkey, and the startup struggles you're going through, too.

i was reading about industrial spills and worker deaths in China and it occurred to me that to work with a supplier that gives a shit about the environment and worker safety (because of government interference, er, uh, regulation), i should buy from American suppliers --- how quaint!

 

[Hippie Dickie]

... idling on the side of the road ...

i just have too much time on my hand, waiting for India to turn the crank ... so i've taken another look at the enclosure design and ... see, i keep checking eBay for laser cutters and found a really nice one a couple of days ago for just shy of $4000 USD ... so that got me to thinking about the current enclosure design (which necessitates a laser for a critical fabrication step) and it occurred to me to go back to the design of several years ago -- The Perfect Cube.

The Perfect Cube is a 2" x 2" x 2" vaporizer. Here's what it looked like in 2006:

The reason i abandoned this concept for the Thermal Cylinder was, really, due to the first PIC processor i got being a DIP chip rather than a surface mount device -- just not enough room for the DIP socket et al.

So with that size constraint out the window these days, the electronics can easily fit on a 1.25" diameter disc (2-sided PCB). Which will easily fit in the bottom 1/4" of the 2" cube. And i'm seeing a lot of ancillary advantages to the cube. Plus, i can make the cube using just a drill press -- no laser required. That's like finding $4K in my back pocket. Cool.

So now i'm busy re-laying out the PCB to fit the new configuration ... i should have that done in a couple of days and get the pcb foundary to knock out a batch for me.

... while i'm waiting for that slow plane from Gujarat.

 

[VWFringe]

a quote for you...

Art gropes, it stalks like a hunter lost in the woods, listening to itself and to everything around it, unsure of itself, waiting to pounce.
- John W. Gardner


and one for me...

All human wisdom is summed up in two words - wait and hope
Alexandre Dumas Pre

-hehe

 

[Hippie Dickie]

Thanks, VW, that post gave me a little extra incentive for working on the new PCB layout ... getting closer to done.

But now i'm a bit pissed at India -- i was supposed to get notification of shipping of the sample glassware on MONDAY. They're already into Thursday over there, so wtf is going on?

And, as a point of user feedback, i finally got to see Bud Toaster #3 last weekend, after several weeks of use away from me, for a firmware download and battery swap -- my soldering iron was punking out when i made that set of batteries -- since then, i've replaced my soldering iron and made 4 more battery packs. So i just swapped the batteries and i'll do a post mortum to see exactly what failed.

But it was disappointing to see how the BT#3 had faired ... the leather cover had come loose, and, much like the failure of Ohm's law to create a simple nichrome heater, the law of friction doesn't do enough to hold the leather cover in place (well, this leather is deer skin, and extremely soft and pliable, but even so ...). So i'm thinking the leather cover must be sewn (maybe riveted) -- now that will add a manufacturing step. (anybody watch "Factory Made" or "How It's Made"? - i love those shows that show how "stuff" is manufactured -- should be required watching in high school).

Even more incentive to change the design back to The Perfect Cube. But i really like the Cylinder, too, and with a bit more effort that could be a very nicely customizable design -- but harder to make and so would have a higher price tag.

Round vs Square, a design delimma.

 

[vap999]

Round vs Square, a design delimma.

Maybe not.

A 2-inch cube fully-integrated Bud Toaster is rather small. Have you thought about making universal Bud Toaster heater cubes, rather than trying to make finished wood cubes? These might be bolt-together or other simple, sturdy cubes that could then be mounted into a wood cylinder or other mounting/power supply/holder.

You could go modular, with the cube fitting in different mountings for portable and desktop use. Going modular could also make warrantees, servicing, and end-use DIY upgrades easier. And with a modular cube, you might be able to become an OEM supplier to other hobbyist-type vaporizer makers and/or you could encourage an after-market of a variety of external holders and accessories. Maybe, in the long-term let others do the external and decorative parts/accesories, while you continue to perfect and sell heaters.

 

[Hippie Dickie]

@vap999 - whoa, man, you are about 5 years down the road on a 10-speed and i'm still trying to get on my tricycle ... but i agree with the sentiment that quite a few opportunities present themselves ... i need to get the first unit done first.

Update on the ongoing saga of outsourcing custom glassware: it appears god had called a rain delay in Gujarat, but the glass factory is now back online after a one week delay ... just as well, since i'm still working on the new PCB layout ... it's almost done.

i'm toying with the idea of showing the blue and green LEDs through the top of the cube. So i need some acrylic rod to pipe the light to the top, but it does simplify processing a little, and i can use surface mount LEDs and eliminate 4 holes in the pcb and the manual step of soldering LEDs to the board. i just need to find smd LEDs with the correct physical size ... the real world keeps getting in the way.

 

[Hippie Dickie]

Thus spake Morpheus ... "You're living in a dream world, Neo"

i feel like i'm continually being smacked up side the head about how un-real my software life experiences have been (i.e. my "reality"), and thus my whole world view. Damn, the real world is messy -- there are no 1's and 0's. Duh.

So i get the samples in only two days from Mumbai to the digital cave (they must have simply flown here) ... and low and behold, the only way the manufacturer could meet the dimensional specs was to not flame polish the cut ends. Now, that sucks. In so many ways. i'm at a loss for words.

i wish they had told me ... i wish i had known to ask. But, in any event, now they have and now i know.

i'm guessing that the material handling grippers on the culture tube forming equipment are larger than the tube length i need ... but i'm still trying to nail that down ... since i know vials can be fabricated in this size (12 mm x 38 mm).

So now i feel like i'm back at square one in terms of sourcing the oven tube glass piece ... did not pass Go, did not collect $200.

Drat!

 

[VB-MFLB]

Hippie Dickie, its been a pleasure reading and watching your progress. Both designs are interesting and hold different benefits in a range or areas. In the end, I like the simplicity, size and covertness of the cube. Though I do like the tubular bud toaster look better overall. If I was to want one to leave out in the open, the cube would be a easy choice. But I'm not one to do that, id rather just put things away then leave more things on shelves and tables, but thats just my pet peeve and it goes for most anything too. Keep on keepin one and continue to bless us with your project.

 

[Hippie Dickie]

@VB-MFLB -- thank-you for your kind words ... they encourage me to keep grinding out the details.

Living in the global village ...

Well, i'm still working out in my own mind how i want to proceed with my India glassware supplier. i went to the hardware store in town and got a new propane torch and had a go at fire polishing the cut end of the borosilicate glassware. i still need to work on technique, but about 30 seconds is enough to do the job without distorting the glass dimensions. So i think i can slog through this next phase.

Now i need to drill the inner piece and try the Bud Toaster using this much tighter tolerance glassware -- only about 0.5mm clearance between the bud vial and the oven tube, versus the 1.5mm tolerance of the current setup.

And now i'm dealing with China. See, after searching relentlessly on alibaba.com, i located two digital thermometers that have a much better form-factor than the units i got on Amazon a year ago (that appear in all the photos).

The new themometers are about 1" in diameter, 1/4" thick, with a flat back ... i'm thinking i can embed this puppy into and flush with the side of the perfect cube - without disturbing the perfection of the cube.

Okay, so using the online comment form on Alibaba, i tried to find out how to order just a few units for testing with my prototype. One factory answered immediately, but the other factory has ignored 4 emails. So i asked the first factory to buy me 3 units from the second factory and that's what they did! i'm simply ecstatic that they did this for me!

i have also changed the design to use surface mount LEDs and having the green and blue LED show through the top of the cube via a 1/8" diameter lightpipe made of extruded acrylic rod, which will be flush with the top face.

This cuts out a few fabrication steps and adds the 3 LEDs to the other surface mount pieces that can be automatically placed and soldered on the pcb.

Now i just need to do my obsessive/compulsive thing with the pcb layout and place the order -- they promise 2 day turnaround on 10 boards.

Progress!

 

[VWFringe]

so cool tigher tolerances - are you expecting better heat transmission?

~ flaming the ends yourself, haahahaa, jeez, i feel for ya'
-------------------------------------

 

[Hippie Dickie]

yeah, i'm expecting better heat transmission ... it just seems logical ... but i'm dealing with reality here, which defies my logic every day.

 

[Hippie Dickie]

Model 14, Version 1 ...

Since the Perfect Cube is such a radical departure (hardware-wise) from the Cylinder, i've assigned the next model number in the sequence.

Here is a view of the new printed circuit board (i thought it looked really cool so i wanted to post it). This is looking up through the bottom of the cube. The three LEDs (the RED, GREEN and BLUE circles) are actually mounted on the other side (top side) from this view.

The MOSFET and the heater coil are also on the top side of the pcb.

The pcb is 1.5" diameter. The cube is bored out to this diameter, except at the top (details to follow after construction of this model, which is in progress). The next inner white circle is the footprint of the 1.25" stainless steel heat shield. There will be a 1/8" air gap for insulation between the heat shield and the outer wood of the cube. The next inner white circle is the outline of the 0.75" diameter heater coil.

 

[stinkmeaner]

The cube design looks really good, not that the leather didn't but the cube maybe looks a little more production for some reason. If you wanted you could even inlay some leather into the cube.

 

[Hippie Dickie]

thanks, stinkm ... i like rounding the edges and corners so it looks like a big dice -- makes it easier to hold in my palm -- i can see it now, the fuzzy dice vaporizer.

i just had an interesting, even if totally non-scientific, observation that i wanted to record in this journal:

Setup:
There is a 1/4" space under the bud vial -- that is, between the bottom of the bud vial and the inside of the bottom of the oven tube. i placed a temperature probe in this space (i'm evaluating some thermometers from China).

Observation:
Vape is running at normal temp - i.e. the heater coil is maintaining 450F, according to the Bud Toaster thermometer reading.
The thermometer under the vial is reading about 370F - probably in contact with the glass surface of either the oven or vial.

Take a toke ... the thermometer reading under the vial, and hence the air temperature, rises to 390F, sometimes up to 400F with a long enough toke (30 seconds or so).

The temperature measured in the middle of the bud in the middle of the vial is reading 420F.

Conclusion:
So that's why the bud doesn't combust, even though the heater is running at 450F. And based on extensive testing, i think 385F to 395F is an optimal temperature range for the hot air to extract the vapor.

Next step:
I need to repeat this experiment with the closer tolerance glassware.

 

[vap999]

A potential problem in interpreting such air and contact temperature readings is that (correct me, if I'm wrong) a substantial portion of the Toaster's herb heating comes from radiation/infrared light heat (which is what you'd expect with a "toaster," with the herb surrounded and blasted by heat radiation from hot exposed nichrome wires). For example, what would happen if you used an opaque herb-holder tube?

 

[Hippie Dickie]

You mean, would a black vial absorb the radiant heat better? Probably.

Although i think contact plays an important part. i can angle the bud vial using the toke tube so it rests against the oven tube -- just a thin line of contact -- but my feeling is the hits are thicker this way -- too much variety in the trichome density to be sure.

 

[Hippie Dickie]

i uploaded two updated code files into my SkyDrive project folder -- a link is at the top of post #1 in this thread.

i finally found and fixed a bug in the duty cycle subroutine (in file: DC.asm)that contributed to massive temperature overshoot at startup - it is much better behaved now.

i also changed a data constant value in VARS.asm related to this.

 

[audiodelic]

Good luck with this project ..... im curious to see the final product.

 

[Hippie Dickie]

Let the adventure begin ...

me, too! maybe i'll get this "final" product built ... just got the new pcb:

i also have all the new parts ... the new surface mount LEDs, some brand new (and sharp) Forstner bits, and even the acrylic 1/8" diameter rods that will bring the LED output to the top of the cube.

Very exciting.

 

[Lo]

Nice Hippie!! Can't wait to see

 

[Hippie Dickie]

Step 1 ... mount the components

Here is the top side with components: 3 chips, 12 resistors, 2 capacitors and 3 push buttons

Here is the reverse side with the 3 LEDs (aren't they just the cutest thing!):

First power test was successful -- downloading the program into the 12F683. This worked (code was verified) and the blue and green LEDs flashed properly.


... next step, drill the cherry cube.

 

[Hippie Dickie]

Step 2: Drill the cherry cube ...

Looking up from the bottom, through the cube and out the top (smallest hole):

First step is 1.75" diameter hole, 1/4" deep.
Second step is 1.5" diameter hole, 1 1/2" deep.
Third step is 1.25" diameter hole, 1/8" deep.
Finally, a 15mm hole out the top.

After considering 3 different thermometers, i'm going with the only one that is round. It will fit into the 1.25" diameter hole in the side of the cube. Here is the cube lying on its side, with the thermometer cutout pointing up:

Cube, top side up, with the thermometer in place:

Next step ... drill the bottom disc to hold the pcb and expose the 3 push buttons out the bottom.