The Screwball by Vapvana

[Zuhdj]

First, the DC PID probably has an offset, or a temperature that is meant as a proxy for the temp of the bowl, I believe. (one of mine seems to have the offset, another doesn't) I'm not sure what it is, I've seen 80 degrees and 100 degrees. In any case, your DC PID is probably fine.

Are the swings during the hit, or some other time?

I'm also curious. I HAVE a dc PID and May run it on there if it'll work better on it. Well see

 

[Vapvana]

While we wait, which temp gives a similar session to something you might get on a mighty, except better? Video?

Here is a video demonstrating the SB at the default PID Temp - 420f

I also used the thermocouple to take the internal temp of the rubies by poking a hole in the middle of the screen. From my personal experiments, it seems like there is about a ~50f offset from the set coil temp to the internal ruby temp.

With a coil temp of 420f, that would put the ruby/air temp at ~370f or ~187c. My preferred temp on the PID is ~465f... which puts the air temp at ~415f or ~212c... which is about the max temp of the mighty (410f / 210c)

IMO, this also explains why the SB will combust at temps of ~550f+ on the PID, because once the air temp is 500f+ it's hot enough to bring the herb into the combustion zone (~450f)

What's the fastest non-combusting extraction for a full bowl?

My preferred one hit extraction temp is ~525f - 535f on the PID with the half sized bowl. Although I know other users set the PID in the 550f to 585f range.

Anything 550f+ on the PID is a 'proceed with caution' temp

Cal mentioned something about the grand opening was shifting here to Q1 next year, I haven't seen a tracking notification for presales yet from anyone however he said they were going out between 13th-30th of this month (or that was the plan)

The countdown on the site is in reference to the Opening Day Giveaway form.

Presale orders are still on track to ship before the 30th, although I'm still waiting for an update. I will be reaching out to all presale orders once I have an updated ETA.

Does anyone know what grade titanium the screwball is made of? I tried searching but didn’t have any luck.

The Screwball housing and bowl are made from GR2 Ti.

The mesh screens and C-Clip are SS, with plans to test Ti versions in the future.

I already have too many ball vapes but i couldn’t resist jumping of the pre-sale kit. Being a diffuser fan, the way the head and the bowl connect is just too beautiful! Can’t wait to try it out!

Thanks for the early support!

I'm excited to get more SBs out in the wild, and I'm looking forward to your feedback.

It’s really fun reading through this thread, all the thinking, testing, explaining and illustrations. I learned a lot and agreed with any other point. The idea to put the holes on the side to prevent dust falling inside the Screwball is genius eg. This was the one and only „negative“ I could complain about. And sadly the wood handle on the bowl broke while „gently“ rattling the bowl out.
This is no critic at all, I‘m loving the Screwball from the first use. Together with my Roor it‘s the vape I like most of all I ever tried.

Every one of my vaping buddies who tried the Screwball felt in love at once too. So I’ll give it to a friend as soon as my kit from the second pre order will arrive.

Really awesome to hear you've been enjoying your experience enough to order another SB!

IMO, there are a few negatives with the SB / ball vapes:

• The Ti bowl gets hot which can lead to seizing in the glass joint, and metal dust rings.
• The exposed coil can be dangerous
• It takes ~5 minutes for the vape to get to temp
• Ball vapes work off heat retention, which has it's limitations

I’m definitely excited to find out when these little beauties are working their way through the postal system. The Screwball will be my first ball vape (and first desktop). I was ready to pull the trigger on a B0/B1 before I saw the pre-sale open up on these. I’d already have the B0/B1, but everything I’ve seen about the Screwball makes it seem like it’s gonna be worth the wait.

Hopefully we can get them before Thanksgiving

@Vapvana Let me know if I can add expedited shipping

Thanks for the early support! And congrats on investing in your first desktop vape.

As long as you have a glass rig with an 18mm joint, you'll be ready to hit it running!

The bad news is it's starting to get slightly unrealistic about shipping out the kits before Thanksgiving...

The good news is I have everything prepared to get the orders out within ~24 hours of receiving the kits.... So my fingers are crossed that DHL can work some holiday magic

@purplenurple24 congrats on your first desktop! Have you ever hit one prior (ball)?If not, in for a real treat This will be my first diffuser style try .. stoked

Thanks for the early support!

It's always fun to add another device into the collection... and I think this will be a nice entry into the world of diffuser style vapes (but don't listen to me... I'm biased after all )

@Vapvana re: diffuser v injector; you're overcomplicating the discussion and oversimplifying your position on the outcome. All that matters is the interaction of the air and the material at interface. You could use a super long injector and run super high temps; if at the point of interface the air mix was at an ideal point for your desired extraction across the material, it will produce the desired results, including low temp deliciousness.

It's sort of like a golf swing, the only thing that actually matters is the physical interaction of the club face and ball at their interfacing point. The idea of a "good swing" is just establishing one particular set of steps some use to achieve a repeatable outcome to the club face/ball interaction. Heck, as a baseball pitcher you have to be able to see that there is more than one way to deliver a strike; none of them are "correct" or "better" in any objective measure.

I agree that regardless of the coil temp, the herb is being vaporized at the same point.

Depending on your vaporization goal, there are different ways to get to the end point (the final temp of your herb). You can go low and slow - aka 'session style'.... or hot and fast - aka 'one hit extractions'

With designing the SB, my goal was to focus on the variables in our control to operate at the lowest convection temps possible, while still reaching the desired end point/temp.

For one hit extractions, variables such as media type/size and distance from the heater to the herb don't make too big of an impact.

However, for session style vaping, these variables impact the heat transfer efficiency and change the experience.

I will take a deeper dive into the role of conduction for low temp vaping in my next post / update.

First, the DC PID probably has an offset, or a temperature that is meant as a proxy for the temp of the bowl, I believe. (one of mine seems to have the offset, another doesn't) I'm not sure what it is, I've seen 80 degrees and 100 degrees. In any case, your DC PID is probably fine.

Are the swings during the hit, or some other time?

@Pcloudy sorry to hear you've run into some issues with the PID. I forgot my DC & Auber PIDs in storage, and haven't been able to do any testing on compatible PIDs.

From speaking with a few other users, it seems like the DC PID has an offset of 80f-100f cooler than the provided PID. From my understanding, the offset is built to show the temp of the quartz banger surface, rather than the coil temp.

@Pcloudy - do you mind sharing how you're taking the temps of the coil? AFAIK, the provided PIDs only show the live coil temp when changing the set temp (I know other versions will show the live coil temp drop after inhaling).

Either way, can you please send an email to hi@vapvana.com with your issues/findings so I can get you situated with a coil/PID replacement if necessary.

Next Update​

Hoping to have a shipping update for y'all ASAP! And I appreciate everyones' patience throughout our startup process

My next update will focus on my theories around conduction heating, and the role it plays in low temp vaping

Talk soon,
Cal

 

[Zuhdj]

I like how this I geared towards a session with a desired end point temp. That's how I've been treating my z8. But the draw is too tight with a larger bowl and it won't vape the larger bowl evenly. Very much looking forward to the screwballs ability to even vape a large bowl with no fear of combustion, even if it is after thanksgiving haha. And especially if it's over a long period of time

 

[Pcloudy]

Sorry for the late response. The coil temp swings were happening while not being used. The most accurate thing I have for that temp range is my terpometer so we can take this with a grain of salt. I was just holding it onto the coil so I know I’m not working with any sort of scientific accuracy.
I will follow up this evening and see if I’m still getting the wild swings. It was just fine for weeks and weeks then one night boom, combustion.

 

[2pumpchump]

Sorry for the late response. The coil temp swings were happening while not being used. The most accurate thing I have for that temp range is my terpometer so we can take this with a grain of salt. I was just holding it onto the coil so I know I’m not working with any sort of scientific accuracy.
I will follow up this evening and see if I’m still getting the wild swings. It was just fine for weeks and weeks then one night boom, combustion.

My stock pid did something similar thing when I wile of sticking/swinging I took it to a friend's house it stopped doing it ...I just figured it nedd a jiggle and starting working .

 

[2pumpchump]

Is there anyone who owns the screwball already and also has a tko? I would love to hear how they compare.

Any body in hear have a tko and not not have a Screwball and have any other spare ball vape as well!!!! ??????? . Edit i love mine so much that I want to shear the experience with other people ... as wining the contest for names put me in a situation where all I can do is watch ... however theirs nothing says that I can't lend it to someone ..
Also keep open in classifieds .. to cover FC rules ....

 

[Zuhdj]

This wait has my VAS tingling. I WANT that flower kettle too lol.

Or maybe some new glass will satisfy

 

[purplenurple24]

This wait has my VAS tingling. I WANT that flower kettle too lol.

Or maybe some new glass will satisfy

Thick Ass Glass is having their Black Friday sale right now. 35% off. I’ve never used their stuff, but I’ve heard good things. Might be worth browsing the website.

 

[TedJones]

Thick Ass Glass is having their Black Friday sale right now. 35% off. I’ve never used their stuff, but I’ve heard good things. Might be worth browsing the website.

Yep, everything I’ve bought from them in the past year HERE, has been top quality and the glass is literally thick as ass !

 

[2pumpchump]

Thick Ass Glass is having their Black Friday sale right now. 35% off. I’ve never used their stuff, but I’ve heard good things. Might be worth browsing the website.

Merry Jane is 25% off if vas is to bad lot of sails on glass right now new rig for your screwball!
Do you prefer a dry or water rig @Zuhdj ????

 

[Zuhdj]

Merry Jane is 25% off if vas is to bad lot of sails on glass right now new rig for your screwball!
Do you prefer a dry or water rig @Zuhdj ????

I ended up with a sky glass lunar bubbler for 25% off. I read the airflow is very free and controllable. That's what I want. With my current bubblers, i can't pull slowly and smoothly like I want. My goo roo he 3 piece is just SO BIG. I've always wanted one nice medium small sized bubbler. This one is 12" tip to tip

It has curbed vas for now. Hopefully this screwball doesn't take much longer haha. I need to save for some things

 

[jbm]

I ended up with a sky glass lunar bubbler for 25% off. I read the airflow is very free and controllable. That's what I want. With my current bubblers, i can't pull slowly and smoothly like I want. My goo roo he 3 piece is just SO BIG. I've always wanted one nice medium small sized bubbler. This one is 12" tip to tip

It has curbed vas for now. Hopefully this screwball doesn't take much longer haha. I need to save for some things

You will be very happy with the lunar. I have it and the splash catcher and it’s very smooth and pleasant.

 

[Zuhdj]

You will be very happy with the lunar. I have it and the splash catcher and it’s very smooth and pleasant.

Do you have any other glass to compare to? Also, removable mouth piece or not? I chose the fixed one but I worry. I like the removable mouthpiece in case I have to replace it. But other than that, I'd mostly prefer the fixed one. I think. I don't like that the mouthpiece of the us bubbler can fall out. It feels unsettling and I like holding my pieces when I hit it

 

[jbm]

Do you have any other glass to compare to? Also, removable mouth piece or not? I chose the fixed one but I worry. I like the removable mouthpiece in case I have to replace it. But other than that, I'd mostly prefer the fixed one. I think. I don't like that the mouthpiece of the us bubbler can fall out. It feels unsettling and I like holding my pieces when I hit it

Yeah, I have a bunch of CC glass and it’s easily as good. I have the removable mouthpiece. It’s been very secure, but I also like that I can switch in a whip if I want. The craftsmanship is pretty great.

 

[coolbreeze]

I don't like that the mouthpiece of the us bubbler can fall out.

keck clip?

 

[Zuhdj]

keck clip?

Aesthetics.


Anyway, I keep trying to use my z8 like the screwball for sessions and it just won't work well. I can't wait for this thing.

 

[2pumpchump]

so the temp agility was a question of yours @Zuhdj
Hopefully my YouTube link is OK to post hear ????

 

[Slimjob Dopamine]

Been lurking for a bit but just put in my order and can’t wait to try it.

I just quit tobacco and combustion about a month ago with the help of a Dynavap M+ and while I love it, I decided take it up a level and was looking at ball vapes and I’m happy I found this page and the Screwball.

The reviews, lifetime warranty, pre sale discount and seeing that the creator is active in the community is what sold it for me. Also the chance to become a beta tester for future products is nice.

I’ve only just started this vaping journey but loving it so far and to me feels like being at the cutting-edge of bud (especially once I get the SB) and being part of that feels kinda cool too haha. I really can’t ever imagine going back to combustion besides being out with friends and I don’t have my Dynavap handy.

 

[coolbreeze]

Been lurking for a bit but just put in my order and can’t wait to try it.

I just quit tobacco and combustion about a month ago with the help of a Dynavap M+ and while I love it, I decided take it up a level and was looking at ball vapes and I’m happy I found this page and the Screwball.

The reviews, lifetime warranty, pre sale discount and seeing that the creator is active in the community is what sold it for me. Also the chance to become a beta tester for future products is nice.

I’ve only just started this vaping journey but loving it so far and to me feels like being at the cutting-edge of bud (especially once I get the SB) and being part of that feels kinda cool too haha. I really can’t ever imagine going back to combustion besides being out with friends and I don’t have my Dynavap handy.

That's a pretty good combo and a great way to start out. One's tethered the other completely free. Both can be powerful or light, one can be "pure convection" or hybrid; both can do conduction. One can be carried in a pocket, the other in a briefcase. ; ) Both can do sessions of various lengths, both can be on-demand. Both are pretty darn effective. Not a bad basic kit. Hope you enjoy it! : )

 

[2pumpchump]

That's a pretty good combo and a great way to start out. One's tethered the other completely free. Both can be powerful or light, one can be "pure convection" or hybrid; both can do conduction. One can be carried in a pocket, the other in a briefcase. ; ) Both can do sessions of various lengths, both can be on-demand. Both are pretty darn effective. Not a bad basic kit. Hope you enjoy it! : )

Actually the SCREWBALL Technically will fit in my cargo pocket if it is cool down and I can fit A j-hook in the other cargo pocket OTHER THAN A STAND!!! So other than your WP _ rig I would say it's actually more compact than a Briefcase..... still salty just joking man

Been lurking for a bit but just put in my order and can’t wait to try it.

I just quit tobacco and combustion about a month ago with the help of a Dynavap M+ and while I love it, I decided take it up a level and was looking at ball vapes and I’m happy I found this page and the Screwball.

The reviews, lifetime warranty, pre sale discount and seeing that the creator is active in the community is what sold it for me. Also the chance to become a beta tester for future products is nice.

I’ve only just started this vaping journey but loving it so far and to me feels like being at the cutting-edge of bud (especially once I get the SB) and being part of that feels kinda cool too haha. I really can’t ever imagine going back to combustion besides being out with friends and I don’t have my Dynavap handy.

Found my self in very similar situation and didn't really know what a desktop ball vapes was and swore I didn't want/ need something like that .. then the desktop ball vapes became a dream.. the FC and @Vapvana Made it come true even though the screwball is #not a ball vape

 

[coolbreeze]

even though the screwball is #not a ball vape

It's the only vape that gets me gem-stoned. ; )

 

[Kiwi Vapor]

Hey guys. 1st post on the forum here too. Have read thousands of posts on Ball Vapes and finally pulled the trigger. Couldn't go past this deal, and the Screwballs intuitive design. Also being from New Zealand, we don't have many options and saw they did international shipping was a bonus. Can't wait for this thing. It's my 1st Ball Vape too and I'm like a little kid at Christmas, checking my emails and the forums daily lol. So pumped to try. Cheers from New Zealand.

 

[Zuhdj]

THE 30th nears. It's cominnnngggggggg )))))

 

[LordKahel]

THE 30th nears. It's cominnnngggggggg )))))

The date was pushed back on the site. It says Dec 1 to dec 8 in the shipping info field. I don't know if it only applies to new pre-order.

 

[Vapvana]

Conduction: Friend or Foe for Flavor? [Part 1 of 3]​

This post is intended to explain my thought process and why I made various decisions designing the Screwball (aka my dream daily driver).

Intro​

Since a majority of my background with cannabis vaping is from concentrates, I had to take a deep dive researching the differences between convection and conduction DHVs.

Before jumping into my opinions, I'd like to quote @Alan from The Convection Thread

While 100% pure convection heating is an ideal goal, the reality is that conduction and radiant heat transfer are always a part of the equation, even though a smaller part.
The walls of the chamber and the basket screen holding the ground material absorb heat from the hot air stream. As they get hot, they conduct and radiate heat. The mass of ground herb also conducts and radiates heat. Some materials conduct / radiate heat at different rates and hold more heat than others. I find that wood conducts less heat and holds less heat than glass, steel, or silicone. More thermal mass of the container requires more heat to achieve the desired temperatures within the ground material.

The process can be thought of as a thermodynamic equation. The controllable factors in the equation for convective heating are temperature, pressure, surface area, mass, and flow rate.
The mass, shape, and density of the ground material is important to the equation. A puck shape, similar to that used when making espresso seems to work the best. If we want even extraction, the entire puck must be heated to the level needed to volatilize the desired plant oils.

Complete extraction also seems to be a tough point to define. The plant material contains a wide spectrum of oil densities. There are some heavy oils and tars within the plant material that we really don’t want to volatilize. Some are only released with the heat of combustion. The most flavorful oils are released at lower temperatures. It all depends upon how dense of oils you want to volatilize to determine your fully extracted point.

Temperature is a fairly straight forward factor to control. The wattage level of the heating coil controls the air temperature.

Pressure within the space containing the ground plant material can be controlled with the draw speed and physical air intake restrictions. A fast draw speed will drop the pressure within the chamber. A lower atmospheric pressure surrounding the puck, lowers the boiling point of the plant oils. This allows oils to be volatilized at a lower temperature. The lower the temperature, the better the flavor. A lower temperature air will also require less cooling before inhaling. The air temperature really only needs to be just hot enough to volatilize the plant oil. Applying too much heat, only requires it to be cooled back down to be comfortable.

Surface area is controlled by the grind of the material. A very fine grind will create a lot of surface area, but won’t be of help if he material packs down so that the hot air can’t reach the material. There is a happy medium in particle size. I find the best way to get good air flow through the material is to hand crush it. The moisture content should be such that the material falls apart after being crushed. If the material has too much moisture, all the water must be driven off before it will be able to achieve volatilization temperatures. The more mass of material contained within the puck, the more heat is required to raise the entire puck to the desired temperature. There should be an ideal puck size for even flow rate and fast heat up.

Flow rate of the air controls the rate of speed that heat is being added to the puck. Too slow and the heat can build up to the point of combustion. Too fast and the heat can be drawn through without reaching the desired temperature. Drawing too fast can also pack down the material in the puck, which reduces the air flow through it. There is a point where the benefit of a lower pressure from a fast draw speed, drops off because too much heat is being drawn away. Getting the draw speed just right can make a big difference in performance.

I think that coffee does provide some good parallels for convective heating and not just from the brewing aspect. The roasting of the green coffee is almost exactly like what is happening with our convective heating units. So much so, that I refer to the process as roasting rather than vaporizing. My units are called “Herbal Roasters”. Hot air corn poppers can be used for roasting green coffee beans, and it volatilizes so much oil that it must be done outside. Turns the beans from green to brown, just like we do with herbal material.

The normal flow of air in a chamber containing the herbal material has almost zero velocity at the perimeter. This makes it tough to get an even air flow rate through the entire puck. Most of the air wants to go through the center of the chamber. If you can force the hot air to enter the perimeter of the chamber/bowl, that would change the profile of the hot air going through the puck. That is what I am attempting to do with my slit end glass heater covers. It has been working well so far. Any brown spots that I do get are at the perimeter, so there is no need for stirring. Getting the air hot enough for a quick and complete extraction can create air that is uncomfortable for inhaling. Having the ability to also use conductive heat transfer at the very end of the roast is nice. The end of the glass tube is closed and round, so it can be used to contact the entire puck for a complete extraction without the need to stir.

Another thing I have been doing is to install a ss foil disc in the center of the heater screen (sandwiched between two screens) to force all of the hot air to the perimeter of the roasting bowl. The ss foil doesn’t have much mass to rob a lot of heat away from the roast. Never any center hot spotting.

To summarize.

Hand grind and puck shape for good air flow, draw speed to lower pressure and control heat rate, force hot air to perimeter, and adjust wattage to suit.

Treat the material as you would a marshmallow. Low heat, slow roast provides the best flavor roasted marshmallow.


Happy roasting

IMO, Alan did an excellent job explaining the different variables involved in the vaporization process (temperature, pressure, surface area, mass, and flow rate).

My goal is to use this post as a reference point to explain my personal opinions.

Let's dive in

100% Pure Convection​

After reading different threads, it seemed like the general consensus was that "100% convection vapes are best for flavor"

Even though it was deemed better for flavor, it seemed like 'pure convection' wasn't actually feasible.

While 100% pure convection heating is an ideal goal, the reality is that conduction and radiant heat transfer are always a part of the equation, even though a smaller part.
The walls of the chamber and the basket screen holding the ground material absorb heat from the hot air stream. As they get hot, they conduct and radiate heat. The mass of ground herb also conducts and radiates heat. Some materials conduct / radiate heat at different rates and hold more heat than others. I find that wood conducts less heat and holds less heat than glass, steel, or silicone. More thermal mass of the container requires more heat to achieve the desired temperatures within the ground material.

The Convection 'Green Ring of Doom'​

Because the air path and bowl also have to absorb heat from the convection airsteam, if the air isn't hot enough it won't be able to fully roast the herb near the perimeter.

Conduction Heaters vs Conduction Heating​

IMO, one of the common misconceptions is around the difference of a conduction heater vs conduction heating.

Conduction Heating​

According to the quote above, 100% of all convection vapes utilize conduction & radiant heating to roast your herb.

IMO, this is highlighted by how the Mighty is communicated - It utilizes hybrid heating via a convection heater.

Conduction Heaters​

Hybrid & Conduction vapes utilize a conduction heater to heat your herb bowl.

IMO, conduction has a bad rep from DHVs that only use a conduction heater. When the only heating element is around the bowl, it will lead to uneven heating around the perimeter and overcooking parts of the herb.

IMO, overcooking is what leads to bad flavor -> aka 'burnt popcorn taste'