Magician needs help building heating element

[Magician007]

I am looking to hide a heating device inside of a hat pin.

I’d like the tip of the hat pin to be able to ignite flash paper, which I believe lights at 150 F.

The battery and switch need to be small enough to be disguised by the design of the hat pin. Heres a picture for an approximate size.

If possible I’m trying to make the heating element able to start by a wireless remote which would be in my pocket.

I’ve investigated heating with nichrome but the batteries and the coil are both way too large.

Any ideas would be awesome and if someone is open to taking this on as a paid project too I would consider that! Thank you !!

 

[Magician007]

Here’s the hat pin picture.

 

[alec_t]

Welcome to ETO.
You might wan to edit your thread title (or ask a mod to do it)?

 

[JimB]

You might wan to edit your thread title (or ask a mod to do it)?

A passing friendly moderator sorted it.

JimB

 

[rjenkinsgb]

I am looking to hide a heating device inside of a hat pin.

I very much doubt that it would be possible to have anything self-contained and small enough to work by electrical heating of the metal pin itself, within the size of the hatpin.

If you duplicated the pin using a stainless steel capillary tube (like a hypodermic needle material), that would allow something to the inserted or threaded through it.

There are then a few possibilities -

A wire through, connected to one of these just beyond the tube tip (with the tube as ground return)
Something like a miniature PTC thermal fuse - 1.6mm long x 0.8mm square.
With the right voltage, that will heat up and self stabilise at an appropriate temperature.

https://www.digikey.co.uk/en/products/detail/murata-electronics/PRG18BC2R2MM1RB/2595387?s=N4IgTCBcDaIAoCUDiBGAHAIQMJgWAsvighiALoC%2BQA

It would need experimentation to find out what temperature it reaches with what voltage.


A wire through plus a spark generator (from a cheap piezo lighter?) if that has enough energy to light the paper.


Or chemical means - a stiff wire "plunger" that can push a bit of a catalyst or reactive material - smoke paste? - to the end of the "pin" ??

 

[ZipZapOuch]

1) Does the project have to be built on THAT hat pin or any hat pin?
2) does the heat have to be at the tip or can it be along the shaft somewhere.
3) how "hidden" does it have to be? (Will an audience member be handling it or will you just pull it out and use it?

 

[Magician007]

Welcome to ETO.
You might wan to edit your thread title (or ask a mod to do it)?

Appreciate it.

 

[Magician007]

1) Does the project have to be built on THAT hat pin or any hat pin?
2) does the heat have to be at the tip or can it be along the shaft somewhere.
3) how "hidden" does it have to be? (Will an audience member be handling it or will you just pull it out and use it?

1)It does not have to be built on that hat pin. I know I will probably have to build some sort of casing to hide the electronics. So the casing can definitely be a bit larger. Just needs to eventually be inconspicuous.

2)the heat should be toward the tip
3)it has to be completely concealed inside the decorative part of the needle. In the best case scenario, the audience member will handle it, and be holding it (from the decorative part) while it heats up the flash paper.

 

[Magician007]

I very much doubt that it would be possible to have anything self-contained and small enough to work by electrical heating of the metal pin itself, within the size of the hatpin.

If you duplicated the pin using a stainless steel capillary tube (like a hypodermic needle material), that would allow something to the inserted or threaded through it.

There are then a few possibilities -

A wire through, connected to one of these just beyond the tube tip (with the tube as ground return)
Something like a miniature PTC thermal fuse - 1.6mm long x 0.8mm square.
With the right voltage, that will heat up and self stabilise at an appropriate temperature.

https://www.digikey.co.uk/en/products/detail/murata-electronics/PRG18BC2R2MM1RB/2595387?s=N4IgTCBcDaIAoCUDiBGAHAIQMJgWAsvighiALoC%2BQA

It would need experimentation to find out what temperature it reaches with what voltage.


A wire through plus a spark generator (from a cheap piezo lighter?) if that has enough energy to light the paper.


Or chemical means - a stiff wire "plunger" that can push a bit of a catalyst or reactive material - smoke paste? - to the end of the "pin" ??

I tried something like the wire through using nichrome wire. It worked but not consistently, and the wire sticking out of the tip was not concealed at all.

I like this chemical idea but again, im guessing there would have to be a motor to automatically deploy the plunger when I’m ready.

 

[rjenkinsgb]

Have a look at the "TCC Incendio" - an igniter built in to a working sharpie marker pen:

Incendio by TCC - Trick

Incendio by TCC - Trick

www.saturnmagic.co.uk

The mechanism in that may be adaptable??

 

[Magician007]

This is very cool.

 

[Magician007]

Have a look at the "TCC Incendio" - an igniter built in to a working sharpie marker pen:

Incendio by TCC - Trick

Incendio by TCC - Trick

www.saturnmagic.co.uk

The mechanism in that may be adaptable??

This is awesome, I’ve never heard of this product.

Seems like it could be adaptable.

The part I’m trying to get over is how thin a needle is. If it’s too thick it will be obvious, so I’m thinking maybe it needs a different method than heating up.

I was considering a laser inside a hollow needle but this seemed too complicated and dangerous.

 

[Lightium]

What temperature is your goal?

 

[Lightium]

Heating of an element:

V * I * t * efficiency = specific heat of the element * mass in Kg * difference of temp in Celsius.


Have a look here:

Cooling and Heating Equations

Latent and sensible cooling and heating equations - imperial units.

www.engineeringtoolbox.com

And here:

Electric Heating of Mass

Electric heating of an object or mass - temperature change vs. energy supplied.

www.engineeringtoolbox.com

 

[Magician007]

What temperature is your goal?

I believe it is 150 C or 300 F to light flash paper.

 

[ZipZapOuch]

Have a look here:

Cooling and Heating Equations

Latent and sensible cooling and heating equations - imperial units.

www.engineeringtoolbox.com

And here:

Electric Heating of Mass

Electric heating of an object or mass - temperature change vs. energy supplied.

www.engineeringtoolbox.com

This is really easy on paper but the radiant and convective heat loss to the surroundings goes up by a non-linear amount as your difference from ambient temperature increases. Especially difficult for high surface area per volume objects (like a needle).

 

[camerart]

Hi M,
Would a piezo spark work?
C.

 

[Lightium]

Hi M,
Would a piezo spark work?
C.

Maybe an igniter from a BBQ grill, but that be too hard to trigger with on hand.

 

[tepalia02]

What about something like these?

HEAT-O - Wearable Heating System

Deal with the cold like a boss in the most extreme environment. | Check out 'HEAT-O - Wearable Heating System' on Indiegogo.

www.indiegogo.com

A Wearable Heating System with a Controllable e-Textile- Based Thermal Panel

Flexible textile heating systems present great advantage due to their ability to bend and hence could ensure uniform heating for irregular geometries. In cooler outer environment, the user requires his/her body to be kept warm for monitoring vital body functions within realistic thermal body...

www.intechopen.com

 

[camerart]

Maybe an igniter from a BBQ grill, but that be too hard to trigger with on hand.

Hi L,
Perhaps true?
C.