Has anyone tried...

[TommyDee]

This could be a fun thread for all those "I wonder if it's been done before?" brain fart moments we all have just moments after a fresh daze passes over us as the vape clears the room. From what I gather, many great moments in history were preceded by an 'alternate perspective'. Not that many expound on what that spark of genius was truly all about.

Okay, so this was my brain fart after finally getting to my daily dose...

Picture this;
Glass tube.
A 14mm long thin stainless steel tube suspended within the glass tube with a fair gap to the wall.
IH coil and driver on the OD of the glass tube.
Screen and load as per usual.
Kick on the induction heater.
Draw

I'm picturing a perfectly clear path in a tube with a passive heater core suspended in the air-path. No wires or other BS materials. The IH should just roast that stainless tube in seconds and put out heat to no end. Even better would be to have the tube encapsulated in glass (halogen housing minus the legs with tube inside) <orders safety glasses> Some of you have played with the IH. I know there are limitations. How badly does this idea suck?

Anyway... What absolutely 'amazing' idea did your last rip present to you? And how long did it take to subside?

 

[TheThriftDrifter]

I like this idea, I have wondered about it myself. I'm sure I've seen it mentioned before. Can't recall who or where though. All glass vapor path would be mint! Quick heat up. Both portable or desktop. Nice Idea.

 

[Ramahs]

Sounds like an induction heater powered G43.

 

[KeroZen]

If the SS tube is in the air path, then it's unclear what the difference with a standard SS heater would be. You heat the metal via a direct current or via a magnetic flux induced current, but in both cases it's the same (and I would guess the later would be maybe less efficient)

Now if it's encapsulated in glass... yes why not. But then why not just using an halogen bulb and spare the bulky electronics of the IH heater, with its capacitors begging to fail over time due to the heat proximity, its fragile second hand FETs from the Shenzhen market, and.... well you get the idea.

 

[TheThriftDrifter]

@KeroZen. With the capacitors, is it because they are close together, that they degrade due to the heat? How far apart would they need to be to lessen or stop the heat proximity issue?

 

[KeroZen]

Yeah I don't know, I somehow assumed it would be in a portable or at least compact form factor, and thus heat proximity couldn't be avoided. But if you get enough space and/or manage to shield the caps from the generated heat...

It's just that electrolytic caps have an intrinsic tendency to dry up and heat accelerates the process. That being said circuits I've seen were using other types of capacitors that might not be so sensitive (ex: plastic film) so it's perhaps a moot point?

But if you design a circuit from the ground up (as seen in another thread of this subforum IIRC) and you source good components... could work. It's just that the drive circuit will always be much bulkier than what is needed to just directly drive a coil or bulb. That plus the efficiency question would be negative points for a portable, but for a desktop we don't care much.

 

[TommyDee]

@KeroZen I said it was a brain fart didn't I? LOL ... but yes, the difference is no wires; [copper], tin, silver, teflon, brass, beryllium, tungsten... etc.

But it brings up the question; per unit volume, does titanium get just as hot as stainless or is it mass based?
Oh, even cooler... it could be a porous metal presenting much more surface area! Something like a metal concentrate pad... which of course leads to the next obvious conclusion... CONCENTRATE! Crap, direct heating of concentrate in a sintered puck in the IH coil! Damn, another fart!

Not worried about the circuit. I am on a kick to make this a belt unit with extra circuitry anyway so quality components is a simple wish on the wish list.


@Ramahs thanks for the connection. Haven't found references yet but a good place to look. TY

@KeroZen. With the capacitors, is it because they are close together, that they degrade due to the heat? How far apart would they need to be to lessen or stop the heat proximity issue?

These capacitors are doing a lot of work. Think of them as batteries being charged and dumped at whatever frequency this RC circuit defines. When perfectly balanced, there is no current, but when things get off-balance, the circuit works to correct it. That work function is converted to heat in the end. But the components in the circuit take a beating. This is where you have to hit the specifications to know if your parts are being maintained within their operating parameters.

 

[KeroZen]

But by all means, please do try it! Don't want to discourage you whatsoever. Just trying to point out the potential short-comings. Even if it's only a desktop unit, people could be interested.