Mysterion999

Well-Known Member
I will confidentially state it is all a matter of volts and amps AND resistance.

Ohmmm.....
I didn't think about ohms, which is why I'm trying to learn by asking.

Is there a formula or can it it be explained to a layman? I really appreciate any help with this. Even if it's something I couldn't build, it would be nice to understand how it works. I understand volts and amps, how does resistance come into play with it all?

I just checked the current draw (?) using my cheap multi meter on my Maud Dib and if I did it right it was showing a draw at the highest of 4.41.

With the meter set at 200 I get an ohm reading of .9 at the 200 setting I get a reading of 2 on my LB. the reason I used the Maud Dib for current is I can't reach the rods with the PS connected on the LB.
 
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Tranquility

Well-Known Member
I didn't think about ohms, which is why I'm trying to learn by asking.

Is there a formula or can it it be explained to a layman? I really appreciate any help with this. Even if it's something I couldn't build, it would be nice to understand how it works. I understand volts and amps, how does resistance come into play with it all?

@OF has seen the thread and he may be able to answer you. He's one of the forum experts on electrical things. From this layman, Ohm's law is V=IR. That is, Voltage equals Current times Resistance.

https://www.physicsclassroom.com/class/circuits/Lesson-3/Ohm-s-Law

I just checked the current draw (?) using my cheap multi meter on my Maud Dib and if I did it right it was showing a draw at the highest of 4.41.

With the meter set at 200 I get an ohm reading of .9 at the 200 setting I get a reading of 2 on my LB. the reason I used the Maud Dib for current is I can't reach the rods with the PS connected on the LB.

If you use your magic computer powers, I suspect you will find many answers around here:

http://fuckcombustion.com/threads/the-magic-flight-box.750/page-1026#post-880733
 

OF

Well-Known Member
Is there a formula or can it it be explained to a layman? I really appreciate any help with this. Even if it's something I couldn't build, it would be nice to understand how it works. I understand volts and amps, how does resistance come into play with it all?

Current (in Amps), voltage (in Volts), and resistance (in Ohms) are linked by "Ohm's Law". Such that voltage divided by current yields Ohms. Likewise, by algebra, Voltage divided by resistance equals current or current times resistance equals voltage. Knowing any two allows you to calculate the third.

https://en.wikipedia.org/wiki/Ohm's_law
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmlaw.html
https://www.electronics-tutorials.ws/dccircuits/dcp_2.html

Like knowing the MPH of your car and how far can tell you how long it takes to get there. Or, knowing how long in time and miles gives you your average speed. Distance, rate and time like voltage, current and resistance.

In the case of LB the actual voltage (considering all the drops) is about 15 Amps at .75 Volts, so the screen part of the box is about (.75 divided by 15), .05 Ohms (1/20 of an Ohm), very close to a short circuit. One of the big issues is there's nearly as much other losses (due to resistance) internally to the 'battery' and connections. And the actual resistance of the SS screen changes with temperature some (goes up a bit).

In most cases resistance determines the current for a given voltage. This is why the same 100 Watt light bulb works on the same outlet a 1500 Watt toaster does. The bulb just has a higher resistance (and therefore lower current). Here, voltage (in Volts) times current (in Amps) gives power in Watts.

Ready for the test?

You can probably do OK with a current limited supply at about 15 Amps with a limit if say 2 Volts? Not an easy task, really. Add to that that you should use fairly thick wires (say 14 AWG) from the supply to the box for such currents and it rapidly becomes a tough job mechanically.

I got some fair results with attaching a D cell with short leads. It tends to hammer them hard, but you can get close to an hour heating under ideal conditions, most of it usefully hot. Using NiCd rechargeables gave shorter run times but rechargeable. The NiMH I tried didn't work due to internal resistance (there's resistance inside), so I used a NiCd from a rechargeable tool I had handy.

All in all I thing MF has done a very credible job. I abandoned my attempts and went with theirs.

Regards to all.

OF

Edit: To expand a bit on this, the Navy used to use 'the water example'. Here pressure (voltage in the electrical world) is measured in PSI typically. Flow rate (current) is in 'Gallons per minute' and resistance (small pipes and other constrictions) determines how many GPM you get for a given PSI. Raise the pressure, or lower the resistance (bigger/shorter pipes) and the flow rate goes up?

Perhaps that help? Prolly not.

OF
 
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Mysterion999

Well-Known Member
Once again OF, I thank you for your time and help. May I ask how often you use your LB? I can't agree with MF doing a credible job with their PS as I have gone through 6 of them in about two years. Some have failed almost immediately and others have slowly degraded to the point that it doesn't heat the trench enough for a good hit. Is it the design of the MF PS that is flawed and pushes the components past their abilities, or is it that they use cheap parts that don't last and fail?

So even starting with a 12v 30 amp PS I can't make something work? Is it because anything that will easily drop the voltage, will also drop the amperage needed to power it?

I still don't understand how the MF PS has such little wires but something I would make needs about a 14 gauge wire. It would be nice to understand this stuff, but I fear it will never happen.
 
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Mysterion999,
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OF

Well-Known Member
May I ask how often you use your LB? I can't agree with MF doing a credible job with their PS as I have gone through 6 of them in about two years.

So even starting with a 12v 30 amp PS I can't make something work? Is it because anything that will easily drop the voltage, will also drop the amperage needed to power it?

I still don't understand how the MF PS has such little wires but something I would make needs about a 14 gauge wire. It would be nice to understand this stuff, but I fear it will never happen.

My usage varies. It might sit for months, then get used several times a day for weeks. Same a VM and others that aren't 'in regular use'. I have one quite worn box, at two others (one one of the first Walnut ones) that don't get used much.

It's a good effort for things like you point out, small wires in the cable? I think what's going on is they send high voltage (probably as AC) and convert right at the contacts. It's sometimes called 'distributed regulation' in big computer systems, with 5 or 3.6 bring created where the load it. A similar scheme is used to get power to your house (or any other 'end user'). Power is conducted at high voltage (and therefore low current for the same power) most of the way. This means very tall (steel) towers with massive insulators to support the hundreds of thousands of Volts. This is reduced (using Tesla's AC over Edison's DC which can't use transformers) to 12,000 Volts (sometimes a bit less) on the tops of the power poles to be further reduced with the 'garbage can' transformers under them to the lines that serve the houses on the street locally. Thus the high current part (due to lower voltage) is short (and less expensive. The same thing happened when we shifted cars from 6 to 12 Volts back around WWII. Doing so made for more expensive batteries (true batteries here since there's more than one cell 'working together') going from 3 cells to 6 but each took something like 2 pounds of copper out due to smaller wires needed. Build a few thousand cars a month, that adds up.

As to home made stuff, I think I just said:

You can probably do OK with a current limited supply at about 15 Amps with a limit if say 2 Volts? Not an easy task, really. Add to that that you should use fairly thick wires (say 14 AWG) from the supply to the box for such currents and it rapidly becomes a tough job mechanically.

I'm still of that opinion, hours later........

Good questions without simple full answers. I've explained what I found, you're welcome to carry on.

OF
 

Mysterion999

Well-Known Member
Again I thank you.

I was hoping I could drop the voltage on my 30A 12VDC supply and add a potentiometer to make it somewhat variable. I wouldn't mind using a heavy gauge wire to run it, but I guess this is not possible.

So when this PS dies, the LB goes in the garbage. It's a shame because I made a really nice looking Orbitor for it and I do like how it performs, but as I've said before, batteries don't cut it for as much as I use it when I have a supply.
 

OF

Well-Known Member
Again I thank you.

I was hoping I could drop the voltage on my 30A 12VDC supply and add a potentiometer to make it somewhat variable. I wouldn't mind using a heavy gauge wire to run it, but I guess this is not possible.

You're welcome.

If you insist you can experiment with your idea. IIRC auto headlights are about 60 Watts each. Five Amps times 12 Volts? We need something like 15 Amps, so 3 such lamps in parallel would draw this amount, give or take. Tweaking the supply voltage up and down would let you fine tune it. A rheostat, not a potentiometer (look each up, there's a very big difference, one has 2 leads, the other 3) to do this is not really the way to go as long as you can adjust voltage. If we want the resistance value it's going to be 12 minus .75 Volts (for the box) divided by 15 Amps, .75 Ohms. The major reason this is not a good idea is while the box needs (15 Amps times .75 Volts) 11.25 Watts to run, 168 Watts or so (15 Amps times 11.25 Volts). Not very efficient, a bit over 5%, while giving you an excellent chance of burning your skin or setting the couch on fire should you get careless.

For the third time, I suggest a current (not voltage) limited supply if you want to play with it.

Or try some headlamps (much cheaper than a one Ohm 200 plus Watt rheostat (closest standard value) dialed down a bit. You might get by with this one if you didn't hold the power on too long (and let it cool between hits:
https://www.electronicsurplus.com/tru-ohm-r150-1r-rheostat-1-ohm-150w

New you'd have to order one from Ohmite (at a bit more bucks):
https://www.ohmite.com/power-controls-rheostats/

You could go with a custom, or use say two 100 Watt units in parallel (or series for that matter I guess) but keep the adjustments close to the same for power sharing.

I advise against it, of course, but it's your call.

OF
 

Mysterion999

Well-Known Member
Thanks again.

I am smart enough to take the advise of someone who knows what they are talking about over my desires to keep my LB as a usable vape. As I said, when this PS dies, so does my desire to use the LB. With that said, maybe this PS will last longer than a month or two once I get back to using it.
 

OF

Well-Known Member
After some thought I decided to dig out my PA (second model) and enjoy a trench or two while poking a bit with what's happening.

This unit has a marked dial, 3 different size 'moons' that rise and set one after the other as you rotate the dial. I use mine with the dial showing the middle moon 'just fully rising', that is the full dot just shows at the left end of the opening. A bit under half way. Here it's 'not too hot' for my tastes, about what I'd expect from a freshly charged battery. The bulb (it's not a LED.....) brilliance confirms this as well as vapor production (which can get pretty subjective real fast.

So the normal 12.2 Volt supply I'm using has a lot of thin cables getting to me so the voltage 'sags' down to 10 or so under load (going in to the box). At my setting it draws about 2.5 Amps, from .75 to 3.4 being possible 'end to end'. From that I'm not sure the 'moon scale' is linear, but close?

2.5 Amps at (times) 10 Volts is 25 Watts. That's going in. The 'switching' supply being used to convert the 12 (or so) Volts coming in to the high current/low voltage needs of the box is probably very close the 90% efficient (ideally over 95 in some cases, seldom much less or heat generation would cause problems. Meaning we probably have 20 plus Watts to deliver?

The numbers 'from MF' are 15 Amps at .75 Volts (a lot of power is 'wasted' self heating the battery) closer to 11 Watts. The PA seems able to 'go colder' than this at 6 Watts or so minimum but close to 30 Watts 'full blast'.

Not an easy task, even without the added burden of putting it into such a tiny, pretty package.

So I think, if we want to make a substitute, we should shoot for a CC (Constant Current) supply in say the 15 to 20 Amp range (perhaps a bit more for the truly serious).

Regards to all.

OF

Edit: I just realized I 'misread' the dial above. Half way would be with the 'middle size moon' straight up, instead the dial as I'm using it is turned further toward 'big moon'......so I'm probably at say 60% not 40?

OF
 
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Mysterion999

Well-Known Member
My sweet spot on a fresh box and PA is 40-50%, more than that and I risk combustion.

Does the amperage output of the supply to the MF PA make a difference if indeed the unit is working properly? Using a 12vdc 2a (which is the rating of the wallwart from MF) supply my older unit barely heats, but if I use a 6a supply it works fine.
 
Mysterion999,

OF

Well-Known Member
Does the amperage output of the supply to the MF PA make a difference if indeed the unit is working properly? Using a 12vdc 2a (which is the rating of the wallwart from MF) supply my older unit barely heats, but if I use a 6a supply it works fine.

"It depends".......doesn't it always. My original unit is on loan (I think) but based on the above tests I'm using more than two Amps, so yes a 2 Amp supply would limit power.

There's always a chance that this is intentional, that is MF is using the 12 Volt current limit to limit power. That is defeating this by using a more powerful source could lead to overheating/failure of the PA?

FWIW I don't recall not having enough power with the first PA model, although I'm currently running hotter that I used to.

OF
 

Mysterion999

Well-Known Member
"It depends".......doesn't it always. My original unit is on loan (I think) but based on the above tests I'm using more than two Amps, so yes a 2 Amp supply would limit power.

There's always a chance that this is intentional, that is MF is using the 12 Volt current limit to limit power. That is defeating this by using a more powerful source could lead to overheating/failure of the PA?

FWIW I don't recall not having enough power with the first PA model, although I'm currently running hotter that I used to.

OF
I had asked you about that a while back explaining that I was under the impression that an electronic component would only draw what it needs. You agreed and that is why I went with the 6 amp supply. As the tool man would say "AR Ar Ar, more power!"
 

OF

Well-Known Member
I had asked you about that a while back explaining that I was under the impression that an electronic component would only draw what it needs. You agreed and that is why I went with the 6 amp supply. As the tool man would say "AR Ar Ar, more power!"

I didn't lie, or at least I'm claiming electricity still works the same way.

I'm suggesting there's a slim chance MF might have intended the 'wall wort' they supplied to limit the maximum power input (and therefore available output) to the PA. Even then Ohm's law still counts because the Voltage collapses to not exceed that current typically. Many 'bench supplies' have this feature, you dial up the Voltage you want, then short circuit the output (generally discouraged) and set the maximum current limit. When you reach that limit, the Voltage is reduced to stay within Ohm's law.

FWIW I doubt that's what MF was doing, but it's possible?

As we used to say in the dynamite business, "If some's good, more's better".

OF
 

Mysterion999

Well-Known Member
I didn't lie, or at least I'm claiming electricity still works the same way.

I'm suggesting there's a slim chance MF might have intended the 'wall wort' they supplied to limit the maximum power input (and therefore available output) to the PA. Even then Ohm's law still counts because the Voltage collapses to not exceed that current typically. Many 'bench supplies' have this feature, you dial up the Voltage you want, then short circuit the output (generally discouraged) and set the maximum current limit. When you reach that limit, the Voltage is reduced to stay within Ohm's law.

FWIW I doubt that's what MF was doing, but it's possible?

As we used to say in the dynamite business, "If some's good, more's better".

OF
I'm not accusing you of anything, I hope you didn't take it that way. You have been nothing but helpful to me
 

Choices

Well-Known Member
Sorry if this is against board etiquette, but I want give a Page 1 “bump” to my first vape. I don’t do it the justice an old and dear friend deserves, but I’m going to be purposaful in using it more often. I know that in many ways it is like when I made myself set aside time to play my long neglected vinyl collection. It made me practice patience in something I enjoy which I think enhances the total experience mindwise. Now for pain relief that can be a different story. When you want GHWW (Grasshopper when working) speed to feel better fast, the ritual aspect can be a frustration....

But it will always be my MFLB. I will never think of it going away if I thin the herd of extra vapes not used much! Long live MFLB!!!!
 

Ramahs

Fucking Combustion (mostly) Since February 2017
Sorry if this is against board etiquette, but I want give a Page 1 “bump” to my first vape. I don’t do it the justice an old and dear friend deserves, but I’m going to be purposaful in using it more often. I know that in many ways it is like when I made myself set aside time to play my long neglected vinyl collection. It made me practice patience in something I enjoy which I think enhances the total experience mindwise. Now for pain relief that can be a different story. When you want GHWW (Grasshopper when working) speed to feel better fast, the ritual aspect can be a frustration....

But it will always be my MFLB. I will never think of it going away if I thin the herd of extra vapes not used much! Long live MFLB!!!!

I couldn't agree more. It was my first vape, and I think more people should be forced to learn to use a vape like this as their first, because it teaches you a bit (or, forces you to learn a bit) about how the process works.

I still try to recharge my glyphs once in a while and pull out this lovely, simple little vape. I never want to be without one in my collection.
 

SpudBob

Well-Known Member
I couldn't agree more. It was my first vape, and I think more people should be forced to learn to use a vape like this as their first, because it teaches you a bit (or, forces you to learn a bit) about how the process works.

I still try to recharge my glyphs once in a while and pull out this lovely, simple little vape. I never want to be without one in my collection.
DITTO!!!
 

vapirtoo

Well-Known Member
Years ago I gave a friend my first beta power supply as I got a newer beta from Magic flight.
Well the new power supply would only work intermittently, but I still use it. I asked my friend if he was still using the original, and he hadn't seen it in years. He finally found it and was going to return it until he tried it. Now he is back on the LB train saying how different and special the effects are! WTF!
 

Mangu

Well-Known Member
Years ago I gave a friend my first beta power supply as I got a newer beta from Magic flight.
Well the new power supply would only work intermittently, but I still use it. I asked my friend if he was still using the original, and he hadn't seen it in years. He finally found it and was going to return it until he tried it. Now he is back on the LB train saying how different and special the effects are! WTF!
I feel like this is very possible with one of those power supplies. It’s toughfinding one online nowadays. I kinda hate using the standard battery.
 

Ramahs

Fucking Combustion (mostly) Since February 2017
The PA's great, like having a fully charged glyph all the time, but you are tethered to an outlet. You can get DC adapters to run it off a cigarette lighter though.

I know, it's supposed to be great...I just don't need it.
Maybe I'll get a used one from r/entexchange or something, if a good deal on one pops up or something one day down the road.
Might as well have one in my collection though, whether or not I use it, to go alongside my MFLB in the ol' medicine cabinet.
 
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