MVT 2

[mistvaporizer]

Been thinking about this for a while now and finally started to work on it. First prototype is nice, I'm really happy with the look, feel and performance.
The big changes are:
1. The touch pad is gone and replaced with a button, internally this eliminates the circuit board and makes assembly easier.
2. The corners have a larger radius so it is more comfortable in the hand.
3. The unit is 1/8" narrower, which isn't much but it is noticeable.
4. The coil is a bit cooler, the abv is golden brown and I didn't combust yet.
5. There is no polarity so the battery can be inserted either way.

the button is recessed

there it is

button rated at over 1,000,000 clicks

and the port holes are still here to view the glowing coil.
I ran a couple bowls through this one yesterday and I liked it a lot. Hope to get a few of these out to testers next week and we'll let the fun begin.

 

[Abysmal Vapor]

Looks cool ! What type of coil is it ? SS316 L wire/mesh or else ? What kind of wood is this ? )
Do the coils glow in operation ?

 

[mistvaporizer]

This is very similar to the MVT. The coil is SS 316L formed in the stacked pancake style. You can hit it when the coils are glowing but as you inhale the air flow cools the coil.
Haven't used it enough to report on battery life. There is the possibility of using a 20700 battery but this one has the 18650
The wood is quilted maple, I used some "scrap" pieces. If you look close there is a line running up and down through the middle. I glued two pieces of 1.25" x 1.25" together for the betas.

 

[Fat Freddy]

 

[sixstringsmash]

Love it! My original MVT is a great little unit so any improvements that can be made on it would be even better!

Got one question in regards to the SS316L, I've heard from a couple different people that when it gets red hot that it tends to oxidize and has a chance of ruining the coil. Is there any reason why we wouldn't be able to use a different material like kanthal or nichrome other than SS316L? Or is it the coil getting red hot a non issue even if it still is SS?

 

[mistvaporizer]

@sixstringsmash the air flow keeps the coil from getting too hot. Also the SS tends to handle the heat nicely. It's been around two years since the Touch came out and i haven't had a burned out coil yet.
I could use nichrome but when i designed the Touch every one wanted SS
The basics of the MVT 2 are coming along nicely and there are three beta units on the bench. Working on the airflow now. The base for the heater has been modified and I have tried a couple of layouts for the air intake and it just keeps getting better. I'll post some abv pics from last nights testing later.

 

[sixstringsmash]

Thanks for the response @mistvaporizer much appreciated.

Since the addition of the button also means the removal of the circuit board would it be safe to say that we can consider the MVT2 to be a full mechanical unit now? This sounds like great news if so because the removal of a circuit board sounds like that's just one less part now that might fail. If we take care of this thing it has the possibility to last us for a very very long time!

Looking forward to those ABV pics! I'd have to say the only real complaint I had with the original MVT unit was it required a lot of stirring. With the funnel and the stir tool it's really easy to stir though so it's not really a big complaint, but if you can get the ABV to a an even brown without the need to stir this would be a complete game changer. Looking forward to what's gonna come out of this thread!

 

[mistvaporizer]

This is some Kushage, a pleasant strain.
The abv is after 3 stirs and a bunch of hits. I could of pushed it a bit more but I was done, totally happy.

The MVT2 takes three hits to produce vapor but great taste in hits 1 & 2. You can ride the lower temps easily. Not sure what battery life is like yet, I expect not as good. My batteries are old so they aren't lasting long. I have new ones on order.
I've a unit in the works that will have greater air flow as an experiment.
@sixstringsmash the electronics are gone but I haven't had any of those fail in the Touch production units so I would say reliability is comparable. The MVT2 will be easier to service and button replacement wouldn't be that hard.
I have tried to simplify the design somewhat but still make it as bullet proof as I could.

 

[mistvaporizer]

The airflow still needs to be nailed down. I redesigned the "chimney holder" which is the part that holds the coil and the female stem (which is like a chimney in this case). These are scrap parts but show how it fits together.

That's the chimney in place.

Here is the chimney holder without the chimney.
It is a wood piece with a circle cut out for the chimney to fit into and holes for electrodes and airflow. The airflow holes are in a "manifold" configuration that lets me tie all the air inlet holes to one intake.
You can see the one hole in the lower right, you can't see the cross holes but those lighter things sticking out from the top and bottom are toothpicks to show where the holes are. That ties all the holes together and gives me a place to valve the inlet.
On the flip side of this piece I have a hole that connects to a slide valve.
The screw in the lower left is one of two that hold the chimney holder in place. Then there is an upright connector that you can see in the pics on the right.
By sliding the block you can change the airflow significantly.

With the valve closed there are still air leaks so you can vape but it is very restricted. With it totally open there is plenty of flow. With it wide open you can combust if you heat the coil very hot and hit it. With the valve closed and a very hot coil it is hard to combust.
Anxious to get this to @paytonpenn so he can put it through its paces.
It took me a while to figure out how to do the valve, now I have to figure out how to have it on the side of the vape. Not the great on the bottom. Any suggestions for valve placement?

 

[Fat Freddy]

Wow! Nice innovation!
Don't have any suggestions on the design but I'm sure many here will. Keep at it!

 

[GetLeft]

Any suggestions for valve placement?

Did you explain how the valve will be adjusted? Mechanically (a little dial perhaps - that would be cool!)? Electronically? Either way, it would seem that having the valves closer to the inlets beats having them farther away from the inlets. But I'm about as far from an engineer there could ever be.

 

[mistvaporizer]

@GetLeft It's mechanical. See the block that is in a different location in each pic? That is the adjustment piece or slider.
I was asking for input on where the slider would be easy to get to. I'm going to go with the side of the unit, around button height.
I just tested this design and i like it a lot. For the first hit i can go hot and wide open and get vapor quickly. Then throttle it down as the glass heats up. Makes it very easy to be consistent throughout the load

 

[Fat Freddy]

Question: the power button seems a bit low on the side of the unit; is it comfortable to depress the power button with one's ring finger? I would think that it would not be so comfortable to use one's pinky finger though.

.

 

[mistvaporizer]

Question: the power button seems a bit low on the side of the unit; is it comfortable to depress the power button with one's ring finger? I would think that it would not be so comfortable to use one's pinky finger though.

.

Ring finger is what i use. Pinky isn't that comfortable but ok.

 

[PPN]

I agree with Fat Freddy the button placement is not the best, I would not call confortable to use the ring finger to depress the button.

 

[mistvaporizer]

I agree with Fat Freddy the button placement is not the best, I would not call confortable to use the ring finger to depress the button.

Actually the button is very comfortable to use with the ring finger. No matter where the button is I don't think using the pinky would be comfortable. Here is a pic of the Touch next to the MVT2, button and touch pad are in the same position. Also the button only depresses about 1.5 mm so you don’t have to press hard. The corners are rounded with a 9.5 mm radius (3/8") so it is very comfortable to hold and the width is 3 mm narrower (1/8") than the Touch.
The height is about 12mm higher than the Touch.
With the valve (or maybe better to call it a carb hole?) and the more comfortable profile this is one of my favorite vapes.

 

[mistvaporizer]

I think I forgot to mention that since the circuit board is gone the polarity of the battery doesn't matter. I've been inserting it negative pole up.

Here is a prototype MVT2 with the slider valve installed on the side.

and a close up of the valve

The slider part will evolve to be more aesthetic but this approach works great. It does add some complexity but not too much extra work and the flexibility you get is wonderful.

 

[Fat Freddy]

@mistvaporizer -- Do you think that over time the slider will get too loose from general wear to allow it to function as intended? Also, the groove seems much wider than necessary for the slider to "regulate" the air port adequately?

.

 

[mistvaporizer]

@Fat Freddy the actual hole placement is based on the heater placement and electrode position, so for now it has to be where it is. The slot that allows getting the slider into position has a lot of dead space on the left side. That is why it is so big.
Still working on the aesthetics. Came up with a better slider piece, SS sheet.

All the space to the right of the inlet hole shouldn't have been cut out. This is a prototype but I'm nailing down the details for the some test units.
As far as durability I'm not sure but think it should hold up well, you only move the slider about an eight of an inch maximum and most of the time you are just tweaking it.
One or two of these should go out next week.

 

[mistvaporizer]

update on the slider valve, I'm not happy with how it is used. A bit too clumsy but damn effective. Today I am working on a new valve design that will involve a thumb wheel and screw. That should look better and be more precise.
I find that without the valve I can overheat the herb if I'm not careful but with the valve adjusted to minimal air flow I can heat all I want, well almost. I haven't combusted with the valve yet.
Stay tuned.

 

[mistvaporizer]

I did a threaded valve with a coco bolo handle

The square space to the left is left over from the slider valve, also this could be recessed but I didn't do that extra work since it is still experimental.
Heres another view

This works very nicely but it is a bit clumsy because it is two handed and it takes several full turns to go from totally open to totally closed. I'm working on another design that will be a half turn to go from totally open to totally closed.
Battery life seems to be good. I got some new batteries but haven't tracked how many stems I get per charge. I'll do some tests next week and post about it.
And the abv

This is one stir and I turned the stem often.
I start with the valve wide open and then turn it down as the unit and stem warmed. I'm really happy with the way it is working.

 

[mistvaporizer]

I think I have the winner. This goes from fully open to fully closed in a half a turn

The center hole is the inlet path. The cut out to the left is from the earlier slide valve build. This has two telescoping brass tubes, the one connected to the "dial" is the inner tube. I'll post some pics of the details later. The dial sticks out a little bit

This is easy to use and effective. I'll put a couple of these together this week and send some off for testing.

 

[mistvaporizer]

Here is the latest proto

The recess on the side that holds the dial for air flow regulation. I haven't decided how I want the dial finished so in this pic it is just lightly sanded, this one is blood wood. It sticks out just a bit, maybe 1.5 mm.
Here is the valve assembly together with the chimney holder.

The other side of the blocks get the heating coil and female 14/23 joint. All the intake ports are feed by the hole in the bottom of the chimney holder. On the right is the chimney holder, on the left is a chimney holder with a maple tube going up and a horizontal piece on top.
This mounts into the frame of the MVT2 like so

On the bottom is the button. On top is the cross bar which directs air in.
The top piece is a maple rod that has a hole drilled almost all the way through. A metal tube (here I used brass but production will probably be SS) with a hole in the side fits into the wood and then another metal tube with a hole slides into that.
I didn't think that metal on wood as the valve would be durable. So for about 22mm of tubing I can add the inner tube and rest assured that valves aren't going to be failing.
The wood dial gets fixed to the inner metal tube.
Here are parts less the wood dial.

I have two prototypes in testing and as soon as I'm happy with them I'll be shipping them out.

 

[Fat Freddy]

The recess on the side that holds the dial for air flow regulation. I haven't decided how I want the dial finished so in this pic it is just lightly sanded, this one is blood wood. It sticks out just a bit, maybe 1.5 mm.

So will the recess on the side have yet another piece on top of it, to allow it to protrude more for a better grip?

.

 

[GetLeft]

Thanks for the updates. Fun to see.
Great work with the dial. That's how I was imagining it from the beginning. Little thumb twirly dial. Looking nice!