Hi! In my latest video I made ferripaste. A cheap homemade alternative to ferrofluid. But how well do the two compare? In this video, I'll do some experiments
with them and even set them on fire. Just to see how they compare... This time I'll have fun with magnetism and fire. Please don't let fire have fun with you... Also be aware of how messy
any type of ferrofluid will be. Let's start by looking at
how funnythey are to play with. Ferrofluid is amazing to play around with but you quickly realize it is very uniform. It forms either a blob or spikes. It may vary between a lot of
small spikes or a few larger ones. But always a blob or spiked. Except under the right conditions
where you may see some thorned spikes. Ferripaste is a better shapeshifter.
It can form spikes... cell walls... plates... ridges... et cetera... You can't really predict
what it will end up looking like. Since this level of variation will make me play with ferripaste for longer periods of time Ferripaste scores the point
for playability - in my opinion. On a more serious note
ferrofluid has some practical uses. For example as a seal
around shafts in hard disk drives. Or as a coolant in voice coil gaps in loudspeakers. The voice coil is heated by the power
from the amplifier passing through it. By applying the right ferrofluid
in the voice coil gap it will help cool the voice coil and even dampen unwanted vibrations - sound -
giving the speaker a clearer sound. It is mostly used in tweeters
but I'm using a woofer because I want to see if the
ferrofluid will stay in the gap. Even when the bass is bumping... The ferrofluid I have is not for loudspeakers. It will evaporate over time
and gum up in the gap. Especially when heated by the voice coil. It may even catch fire
at full volume during a party. It also has very low viscosity
so it may splatter all over the place. Lets' see. No? No, it is doing well. The magnetic field is strong enough
to hold the liquid firmly in place. Even the ribbed coil pumping
hard in it will not make it splatter. Impressive.
Let's try with ferripaste. At first, it looks promising. It reacts like ferrofluid. Except for the brown liquid forming... It seems to separate and it no
longer looks promising at all... When I assembled the speaker for test again There was a clear problem. The cone wasn't springy anymore. The separated magnetite was locking
the coil in any position I pressed it down to. Nevertheless, I tried playing some music on it. There's still no splatter. However, it clearly wasn't working well. No matter the polarity,
when hooked up to the amplifier The coil would always sink down and stay low. I tried taking the cone off and test
in free air with a separate magnet. But it only got worse... The ferripaste does NOT like
the heat coming from the voice coil. I tried turning the volume
down a bit, but little did it help. Well, that's the weirdest clip
you'll see from me for a while... *Cough, cough*
"Oh god, that smells." Obviously, ferrofluid wins here. It has some unique practical uses,
that ferripaste simply can't match. The next test will be how well
they can detect tiny magnetic fields. I have shown earlier how ferrofluid will visualize the magnetic
stripe on a credit card. Here's another obsolete credit card. The trick is to get a thin layer, and... There you go. Ferrofluid easily shows the two
magnetic stripes on this card. Ferripaste, on the other hand is too thick and granular
to show such small details. I tested ferrofluid on a low-capacity HDD too. But didn't see anything. On a VHS tape it shows the pulsed control
track at the lower edge of the magnetic tape. I didn't see the analog video and audio tracks. The smallest tracks, I saw with ferrofluid were on a good old floppy disk. They are barely visible with the naked eye. But zoomed in you can see the circular tracks. Since only ferrofluid is
able to show tiny fields it's another win for it. The clean-up? Aaarrggghhh...
The clean-up.... They are both horrible in this respect. Ferrofluid can seem impossible
to control and contain. It will find and hide its nano-
particles in cracks and creases you didn't even know exist. Ferripaste is like a motor oil based paint. Imagine playing with
that in your living room... Honestly, they both lose a point in this category. Shame on both of them! How about storage? This commercial ferrofluid must
be kept in an airtight container since the petroleum will evaporate if left in the open for a prolonged time. But the magnetite and carrier fluid will not separate. The temperature alone is
enough to suspend and mix the tiny magnetite particles by brownian motion. To my knowledge the ferripaste will not evaporate. But I haven't had it for enough time to be sure. However, the magnetite particles are bigger and will slowly sink to the bottom. You will need to mix ferripaste
again after long storage. Since ferrofluid will never separate and always is ready for action out of the bottle it wins in storage. Just make sure it is in an
airtight and spill-proof container. Yeah, uhm, I've always
wanted to see how ferrofluid burns so - for safety reasons? - we'll
test how easily they catch fire... At first I tried directly on
top of a sphere magnet. I thought I could get away with using a tiny amount of ferrofluid forming spikes on the top pole. It didn't work as planned
but for a failure it is quite interesting. Notice what happens when I try to set it on fire. There seems to be
some form of convection. I wasn't able to light it on fire,
so let's try a different setup. For something flammable,
I was expecting a bigger blaze... Have some patience.
I will not give up! *Loud flame from a gas burner* The ash is mostly magnetite and still
useful for detecting a magnetic field. Ferripaste should be even more
difficult to ignite based on the flash points. But with higher spikes and without convection I may be able to ignite it. Oh... Okay...
It just lights up like a candle... Once again, the magnetite is left behind This time as some crumbly spikes. Don't use any of these near
a candle or your smoking uncle. But ferrofluid seems to be the
hardest to ignite in small quantities And wins the point. Last, but not least the price is an easy win for the ferripaste. It is around 30 times as cheap! The bottle of ferrofluid,
donated by supermagnete.com is worth over 400 euros. While I made 1 kg of ferripaste
for around 150 danish kroner. Equal to around 20 euros. Ferripaste takes the last point
and it's time for my conclusion. In the seven categories I have chosen ferrofluid is a safe winner on points. 3 to 1. Still, price and playability may matter the most so ferripaste isn't a total loser. I'll place links in all the usual places to the video about how to make it. Thanks for watching. I hope you liked it enough
to click the thumbs up button. And maybe subscribe
because in an upcoming video I will unbox something very special
for all you big magnet lovers out there. There's a new monster in my house...
