It's not the size, it's the _GAP!_ Clearance of 1-2mm all-round will slow the magnet way more than 3-4mm. 👍😎 In your last video you can see how a thin plumber's pipe with a small gap to the magnet is MORE effective than a thicker copper pipe with a larger gap.

@GregorShapiro

3 ай бұрын

@Robinson Foundry Cast a new copper tube with a smaller inner diameter to fit one of the magnets (the big one) better, perhaps turn the ID to a gap tolerance of about 1 mm?

@subliminalvibes

3 ай бұрын

@@GregorShapiro I missed his reply... Was it informative?

@T_B

3 ай бұрын

So, what you are saying is.... mind the gap.

@markbernier8434

3 ай бұрын

Inverse square law at work.

@dingusbingus8554

3 ай бұрын

Came here to say this

A furnace made out of a keg?!!! Brilliant!!!

I use small neodymium magnets in projects all the time and keep a variety of them on hand. People are amazed at the power of a 1/2" disc X 1/4" thick N52 grade magnet when I demonstrate them. And I keep a 1" N52 sphere and a 4' length of 1 1/4" copper water pipe on hand to demonstrate Lenz's law also. Even being familiar with it it never ceases to amaze me at how long it takes to drop through. That 3" magnet you are playing with is a monster. Be vigilant with it especially around the other large magnet. By the time you realize you made a mistake you may have already lost a finger. I've had a 1" magnet bite me pretty good and it happens fast.

@tradde11

2 ай бұрын

I have a bunch of smaller ones. And you're right their pull is much more than one would expect. I don't want to mess around with big ones as I like having my fingers intact.

@akyhne

2 ай бұрын

The magnet in the video is tiny compared to what the KZreadr Brainiac75 has.

@Jonb173

Ай бұрын

It’s true I lost 2 fingers to magnets.

@tradde11

Ай бұрын

@@Jonb173I am sorry for your loss. Sometimes we don't realize how dangerous some things are that don't appear so.

@souljunkee33

3 күн бұрын

​@@Jonb173thank you for sharing😢 that's intense I have had a magnet bite me once that now I have rules. And I've told people does the big ones can take your fingers but I don't think they believe me... So I'm adding your anecdote and life experience to my spiel when I share and teach with magnets. So again thank you. I started this method of rulemaking after I was injured by a table saw from a kickback of MDF and it was actually a man that I worked with that had lost four of his 10 fingers to a saw in the shop that we worked at that cemented the ritual of rulemaking and rule rehearsal every time I turn on my saw!

Thanks for including the tube roll/levitation part! Clearly shows how the field acts like a fluid. Well done

Idea... Polish you copper tube really well so it will spin on bearings laying down like u shoeed at 8:30 , but power spin the copper tube via belt connected to a motor so the tube spins and plce the magnet inside and see how stable the levitation is

@erich_kubart

3 ай бұрын

I was going to suggest the same thing - spin the copper tube like rolling it on the table but in place to show the magnet hovering in the middle of the tube

@starechomic

3 ай бұрын

I bet there's a rock tumbler that would work perfectly for that application. Would be cool to see

@gorazd68

2 ай бұрын

This way you would end up building electric motor eventualy.

@sadface

2 ай бұрын

@@gorazd68 Or a generator, which might be worse...

i am glade you are being less camera shy and good job with all the videos.

@robinson-foundry

2 ай бұрын

Thank you!

@TUBETIMESHORTS

2 ай бұрын

Thanks For 11 subscribers 🎉

@germanengineer8134

2 ай бұрын

@@TUBETIMESHORTS ?

I have seen this Over a thousand times but like a moth to a flame I am ready to see it again

@douglasboyle6544

2 ай бұрын

I'm exactly the same way, it is just such a crazy thing to watch.

@brian8410

2 ай бұрын

Anton Petrov's channel just did a YT vid on why insects are drawn to light and it's probably not why you think...........in case you are interested.

Next time you should do this, try letting your copper cool naturally instead of quenching it. Your cystaline structure of the copper will be alot different, they will be alot tighter structure. Your eddy currents alot different.

@brnmcc01

25 күн бұрын

Cooling copper slowly hardens and crystallizes the internal structure. Quenching and cooling it as quickly as possible anneals and softens the copper, all copper wire is annealed. I'm not sure that this makes the wire a better conductor so much as helps prevent the wire from work hardening and fracturing which would definitely not be good for electrical wiring...

@ronaldweller7438

22 күн бұрын

😅😅

@cackles1005

22 күн бұрын

It is true that slowly cooling will improve conductivity, but only partially due to physical structure. Rapid cooling causes high internal strain, which can cause macroscopic cracks, but also produces crystalline shear and can even prevent crystallization, resulting in zones of amorphism. Generally speaking, improving crystalline ordering improves conductivity, so a slower and more consistent cooling should result in higher conductivity. Shoving the whole thing in a bucket of kieselguhr for a week or two would let it cool as slowly as reasonably possible via passive means - a tightly regulated programmable kiln could lengthen cooling time even further.

Really appreciate your efforts, time and expense ..for this experiment. Thanks👍👍

A suggestion for you from a guy who has (probably) no experience with any of this -- look at the video @5:25. You have placed a constraint on yourself by pouring into the smaller gap in the mold. I suggest you rotate the mold 90 degrees so you can pour into an opening several times larger. I follow this recommendation while pouring cement from a mix truck off a chute and into a foundation form. I guess I have many tons of experience with this sort of thing after all! Excellent video.

@robinson-foundry

2 ай бұрын

Haha yes I realized that while editing the video! Such a simple solution. Fortunately I had more than enough this time! Thank you!

@johnkemas7344

2 ай бұрын

Also lets you pour much faster to give a better fill quicker.

@deerazor8280

2 ай бұрын

Tons or tonnes

@hughtub

2 ай бұрын

I thought for several minutes trying to understand what you meant by rotating it 90 degrees. I think you're trying to describe positioning the pour such that, in the linear manner in which it sloshes, the slosh will be more along the arc, such that, as it's being poured here at the "3 oclock" position, keeping the molten pitcher in the same orientation but rather pouring into the 12 o'clock position means you have several inches of curve to catch drips rather than limited to the width of the hollow.

@AKG58Z

2 ай бұрын

I thought the same thing

Your molds are cracking because the plastic is expanding during the burnout, you can get 3-D printing, filament, specifically for burnouts.

@NightRunner417

2 ай бұрын

Also I think it would have fought him less if he'd printed more hollow, or totally hollow. A simple taper on the inside near the top and one could easily print it hollow with very thin walls. Bonus points for less overall material to eliminate.

@richardkelley1646

2 ай бұрын

Plastic shrinks when it's heated !

@NightRunner417

2 ай бұрын

@@richardkelley1646 Behavior isn't strict black and white like you want it to be. Anyone that works in plastics knows it has _stresses_ in it that cause it to _warp_ when heated past its glass transition temp, not just shrink. This is why casting plastic blanks into other materials is such a bitch. Take a simple model of whatever and heat it to say 210 and it won't just get smaller, it'll mutate in all kinds of crazy ways, bulging here and indenting there, and there's no telling where it will warp until it does. This is why low warp plastics are such a big deal in 3d printing. NOT LOW SHRINKAGE, low WARP.

@Ropetangler

Ай бұрын

I'm no expert on this subject, but could you use candle wax instead of plastic for your form , it should be easier to burn out without stressing your ceramic mold.

8:30 Put the copper tube sideways on a rock tumbler, that keeps the tube rotating, so the big metal disc magnet floats in it suspended for as long as the rock tumbler keeps rotating the copper tube.

@Metal_Master_YT

2 ай бұрын

nice idea!

@kevpatt

Ай бұрын

What's interesting too is _why_ the magnet floats in the center when the tube is rotating: When the magnet is off center, the copper rotating past the magnet is going thru a _gradient_ in the magnetic field. That is, imagine a point on the tube approaching the magnet. As this point rotates, it gets closer to the magnet, then as it continues rotating away, it gets further away from the magnet. So the strength of the magnetic field that this point of copper experiences is constantly changing, and it is this _changing_ magnetic field strength that actually induces the electric current (and opposing magnetic field) in the copper. This opposing field tends to push the magnet away, and any part of the tube that is closer to the magnet will also push it away in the same manner. Thus, the magnet gets pushed toward the center. If the magnet's poles are oriented coaxially with tube (as it is shown in the video), there is actually no current induced in the rotating copper tube if the magnet is perfectly centered, as the field is uniform all around. Of course, gravity pulls the magnet downward, so it is always a bit off-center toward the lower part of the tube, which constantly pushes it back upward toward center. All of this is the principle behind homopolar magnetic bearings.

NICE demonstration ！！！I believe this is the true beauty of experiments which you can never imagine with mere theories and excercises on the textbook!

You should try making a simple squirrel cage motor with this setup.

Here's a project and experiment for you. Take the magnet (ball, disk, bar,etc.) and a copper pipe/tube, wrap the copper pipe with transformer wire, connect the ends of the wire to an ammeter, and/or voltmeter and check for amps and voltage if generated and transferred from the coil to the meter. Turn the magnet over so that the magnetic field is reversed and see if the amps or voltage changes. LMK your findings!😊

I loved magnets since I was a very young child and have a large collection. I am now in my 60s and I was so excited when rare earth magnets became available. I have so many shapes and sizes and some that are to large to play with casually. Ive got bitten by some large magnets a couple of times. Luckily no broken bones but some massive blood blisters. Love your experiments.

9:27 YESSSS I was thinking that would be a super cool shot just a few seconds before you did it. Having the string fall down at normal gravity speed while the magnet just slowly meanders down the pipe, so cool

Awesome demonstration. Foundry skills galore.

Wonderful demonstration of your kiln work n magnetic magic

Wow! Really impressed w the way u did everything, such a cool effect

I would have to say you did a very good job of pouring that

Thank you for this great video Bro🙂🤝🤝🤝

Reluctance or, more commonly, reactance are the words you're looking for. It's the resistance to changes in magnetic and current direction. It's mostly used in inductors that are paired with capacitors for frequency regulation and filtration. Lenz's Law makes it so that the magnetic field generated by a current resists change in the current's strength. It stores magnetic energy like a capacitor stores electric energy. As a current drops, the magnetic field shrinks at 90° to the wire it's flowing through. As it does, it crosses the sections of wire next to the section it's coming from, generating electric current. As the strength/direction of the current changes, the resulting magnetic field will create an opposing current. Regular changes in the current (the frequency) simply create an imperceptible delay in direction, but irregular changes, such as signal noise, end up "blending" for lack of a better term, into the dominant/resonant frequency. This was an oversimplification of what is happening, but proper detail would and does require a solid 10-20 pages of theory, maths and examples... You know. Like you'd find in a textbook. Or at LEAST an hour video, but more like 4-6 hours like you get in a week of Electronics Engineering lectures and demonstration in college. Plus the additional hours spent practicing calculations, circuit experiments, doing homework, etc. Most of your first year of EE is spent learning this stuff, averaging one or two physical parts per week; the theory, maths, and application for each. Ah, the memories. I can still smell the blown caps and fried transistors almost 20 years later. 😊

@polosandoval

3 ай бұрын

Ah yes, the magic smoke...

@HangarQueen

3 ай бұрын

Came to the comments looking for the magic word, "reluctance" -- before posting it myself. TY. :-)

@marcmillis3867

2 ай бұрын

They didn't tell you about the "Energy carrier" .... A collapsible elastic solid... Magnetic energy= a rotation in a medium, électrostatic energy = a tension in a medium... So physical space is 1 positive tensionZ & 2 negative pressuresXY. And what we see is Weber's law of 1846....

You can use the same phenomenon to launch aluminum discs from the top of a flattened conductive coil when AC current is applied. A thin rod is usually placed in the middle of the setup to constrain the motion of the aluminum disc, otherwise it will tend to simply slide off to the side. Aluminum is better for this since the metal is less dense than silver or copper. The conductive coil can be made from some copper wire. Nothing fancy is needed, just a switch or a voltage controller and conventional residential wall power (standard 60 hz 120 v AC works fine).

Extra points for mic'ing yourself well, and for the good amount of provided light. Yay! I do wish you'd looked at Lenz's law more. Oh well.

Just mind-blowing. Wonderful.

Sweet - what a beautiful example!

I really like restoration videos. That, and a powerful case of OCD led me to suggest chucking the copper tube on a lathe, facing the ends, OD, and ID, and then polishing them. That would be so cool if you have the tools.

Gran video. Además de un laboratorio con muchos recursos, mucha valentía en realizarlo.

Amazing work Rob, love you

This is a really great concept to illustrate magnetic braking, or other principles that involve eddy currents. In magnetic braking, this concept is very similar to how actual magnetic braking works. I always like to show off this scientific concept to friends and family, as they are perplexed on how a magnet could slow down significantly on a copper plate due to resistance through the creation of eddy currents within the copper plate. Anyways nice video!

it gives hints and ideas to do some thing further

This is really interesting. Maybe you could suspend the larger copper tube onto a vee block with roller bearings as contact points and spin the copper tube to try and get the large magnet to float in the middle. Great video!

These eddy currents display a really cool effect

You share your mind . We learn from you thank you .❤

You should make a tall 10 foot clear plexiglass tube that sits on top of the copper. Drop the magnet in the tube see how much it slows it down

Super chill the copper and the magnet.

Nice enough to suggest where to skip ahead to... I subscribed immediately. Thanks

Thx for the video!

I enjoyed seeing this done at this larger scale. One thing I can think of is to put the copper tube horizontally on rotating rollers , then see if the magnet floats in the center.

Good usage of appropriate safety equipment 😁

I'm not boasting or anything and I know those magnets are massively powerful, but their power does not extend far from their surface. I used to be an MEI and CT Scanner engineer and we got to play with truly awesome magnets. We used to get the junior doctors to hold part of the aluminium safety rail and literally RUN at the magnet. They would never get there, because the magnet would slow them down to a crawl before they hit it. MRI's are fun, just a bit unforgiving.

It's been 10 years since I saw that, it's great!

Suggestions:- Degas the liquid copper. Buzz bars are made from Oxygen Free High Conductivity copper. Ensure the inside of the 3d print is vented to atmosphere before burning it out. Add a 3 to 4 inch diameter sprue on top of your 3d print where you poured the liquid in. This will help with pouring. Having a larger surface area to volume ratio it will remain liquid longer so keep feeding the part with liquid as the copper contracts and solidifies in the part. The hydrostatic head also helps with porosity. Add a similar diameter riser on the other side to vent the part while pouring and feed the part while solidifing. Chills are added to sand molds to make grains smaller. You want them bigger so wrap part and feeds in ceramic wool so it cools slower allowing the copper grains to grow big. Don't forget to cover sprue and vent after pouring. Cast at a higher temperature. Use molochite instead of silica from layer 2 or 3. It is a lot cheaper. If you are using E-glass cloth you could wrap the outside with it as it will soften and sinter at orange/yellow heat. As others have said reduce the air gap between the magnet and copper. See Ben's video on magnetic materials at Applied Science.

Thanks sir.. You clear my doubt of what actually magnet feels in copper tube... . I know that magnet get slows down in the copper tube... But i didn't know of what it actually feels to it... . And when you tell that it feel like viscous fluid.... I got clear of it.. 👌👌😇

I propose to create a Gauss gun, where using the casting method you can create a powerful induction coil with a relatively small number of turns but a large wire diameter. One formula that describes the inductance (L) of the coil is: L = (N^2 * μ * A) / l Where: L is the inductance in Henry (H), N is the number of turns, μ is the magnetic permeability of the medium (for an air coil, approximately equal to μ0, the permeability of vacuum), A is the cross-sectional area of the coil, l is the length of the coil. This formula shows that to achieve a higher inductance, you can either increase the number of turns (N), or compensate for fewer turns by increasing the cross-sectional area (A), which includes using wire with a larger diameter. Thus, increasing the wire diameter with a small number of turns helps create a powerful induction coil

Cool! I enjoyed the watch! you should definitely try to find a way to purify that silver, sterling silver isn't pure enough, and you need close to 100% purity to take advantage of the extra conductivity.

Fun video. If you were to rotate the mould through 90 degrees and pour along the length of the opening the casting process would be a little easier. Great video though, and good to see you onscreen!

Great work @

Definitely make the ID size more exact to the size of the OD of the magnet if you want to see the best results. The closer the better. That's why a magnet that's literally sitting on a copper sheet then sloped at a near 90° angle will move extremely slow.

Since the molds crack pretty much every time, why not use the fiberglass cloth while building up the layers? Not for every layer, certainly, but using that instead of the silica sand for one in the middle should help.

@cheebee2659

3 ай бұрын

yeh i was thinking that superslurry stuff is shite too :D

@iolithblue

3 ай бұрын

For what it's worth I agree, but it makes removal of the ceramic much harder after casting.

As others have suggested, matching the diameter of the tube closer to the diameter of the magnet yields more impressive results. I like to use a steel ball and a ball magnet of the same sizes in the copper plumber's tube as a fun demonstration.

Magnets are always fun. But this is super cool. Thank you from us without kilns and all that to try it ourselves.

@robinsonfoundry that is a really awesome project and demonstration! The amount of resistance or "coupling" between the magnet and the copper is obviously influenced by the strength and size of the magnet, but it is also a factor of the smallness of the gap between the magnet and the inside of the copper tube. If you have a cylindrical magnet whose diameter is very close to the inside diameter of the tube, the effect will be even more dramatic. You might consider re-casting your copper tube so the inside diameter is just a bit larger than your magnet, say 3.125".

I imagine you have seen some of the older vintage foundry films like British Pathe’s ‘Casting In Iron’ and such. I have always been fascinated by the large hand wheel and gear systems that factories use to pour molten metal. I have been thinking about trying to build one of those for a few years but just don’t think my little jewelers electric foundry is up to the task of justifying the build. I feel like a pouring frame for heavy crucibles might be just the ticket for you.

Awesome ... reminds of when I worked in a Gold Refinery !!!

I used an 18" length of aluminium tube and an N52 sphere with a couple of millimetres at either side between the sphere and the tube. The effect lasts longer thus more impressive. I used it at work as an ice breaker. It became known as Andy's Magic Pole.

Always get excited when you’ve uploaded

I’ve seen someone swing the magnet at a chunk of copper and before it crashes into it, at least what you’d think would happen, it’s like invisible brakes are applied to the magnet and it slows waaaayyyy down and just touches the copper. Looks really trippy, might be a neat effect to show. I found a small neodymium magnet at work and spent waaaayyy too much time dropping it down a 1/2 copper pipe. Took like 5 seconds to travel 2 feet.

Thanks, very interesting ! One cool thing would be to put your copper cylinder horizontaly on 4 rollers with 1 or 2 rollers powered by an battery drill so it can spin and with the magnet in the center, as far i can see with your short demonstration, i think the magnet will levitate into the copper cylinder. Would be cool and love to see that.

Excellent video! I'm now a fan and just subscribed. I noticed a few comments suggesting you put the copper tube on its side and rotate it in order to see just how well the magnet levitates -the rock tumbler idea sounds cool and very simple . Can we expect to see a video like that any time soon? Really great job!!!

I've heard about eddy currents. This is way cool on a grand scale!

A suggestion id like to see... If you put a hand scale on the rope and pulled the magnet through the copper to see the resistance in pounds/grams. I enjoyed the video and your effort😊 thanks 👍

It seems there must be a way to free energy along this thought process.

That is one dream hobby/DIY shop

It will be found possible to get more power out of a properly aligned and moving magnetic configuration than is put into the device. I have this from a good source, so dont give up on your playing and imagining using magnets. There is a lot left to be discovered from these forces and also don't minimize your own ability to intuit and discover new phenomena regarding these forces. Good luck man. It could be you that gets us to zero point! We are close!

excellent 👌 perform ❤ this is a future of our next generations technology 👈😊😊😊

To ease pourring, next time you can try to turn the mould 90 degrees so as to pour into the long edge.

@lawrencemanning

3 ай бұрын

I was thinking a small lip all around the od and id wouldn’t have complicated things much, but that’s probably better.

Years ago, I worked for a company by the name of Thomas & Skinner, we made transformers and magnets, a large neodymium magnet was on a workbench, ready to be packed for local shipping, a tow motor came too close and got slammed by it, very funny to see and scared the driver to death.

@user-nf7tt2uo1r

2 ай бұрын

Were you the driver?

@AdamosDad

2 ай бұрын

@@user-nf7tt2uo1r No I was a maintenance man that worked on a bench next to the magnet packer. Some things just make the work environment more fun.

Nice work brother!

I saw a video once of a guy heating up water with copper pipes and magnets. The magnets where on a sort of a rotor moving them past the copper pipes very fast. Resulting in the pipes getting hot. And that heated up the water. It would be cool if you could do something of that sort with the copper and magnets.

I like your Anheuser-Bush melting furnace!

Excellent video.

This would be an awesome re-design of the drop zone ride. Have one big long pipe with sections of copper and glass. When you hit the glass portion you drop fast, then the next portion is copper, so it slows you down. You could design it to speed up and slow down. The last section near the ground would be copper and bring you to a stop. It would be the safest ride in the world!!

Something that Ive always wanted to do is make a very tall shaft that you can attach the big magnet to with a very long string and or solid rod. Swing the magnet over a very long arch of copper runway and watch it start off vary fast and then glide to a nice soft stop. Or have a nice thick copper plate at the center point of the pengulu that arrest the magnet swing. Kind of a motion copper/magnet ART project.

AWESOME I want ANOTHER 20-30 years of LIFE TIME! I am TOO OLD to only be learning this NOW!

Great video! I really loved the part at 8:05

Thanks for sharing.

Amazing!

Great video, it could be fun to see if you cut the tube so it does not connect all the way around and then bridge the gap with different resistors, a LED, maybe graphite and other things.

I’ve heard but never seen done is stacking rings of conductor stacked insulated from each other to focus the field

Just a thought for you. When pouring it's easier to hit the target by positioning the spout left-right but not forward-backward, because the spout focuses the pour position L-R. The F-B accuracy is dependant on your flow control consistency, which is much poorer and especially if it's heavy. So pouring into an annulus should be done tangential not radial.

Great video Man! 👍 Top notch stuff... I'm not trying to one up you, but I thought I had heard of magnets stronger than n52's but wasn't sure So after a little searching I found this N55 magnets are the strongest grade of commercial neodymium magnets available today, rare earth neodymium magnets have a strength measurement range of 24 mgoe-55 mgoe, this powerful neodymium magnet is about 5-6% stronger than N52. Looking forward to your next video. Cheers

Really? If this is the kind of weird stuff you do…..I’m totally IN!

Get a magnetic ball to drop down and see if it behaves differently. Still going to recommend the magnetic slide from your last video - line up a bunch of bar magnets to form a slide and then let different metal disks slide down them to show the effect.

Nice experiment. It would be nice to see the copper suspended in space with the magnet spinning inside to see if the copper will also spin with it

Wtf, this video has been uploaded 15 hours ago but the first part of the video is a complete dejavou, including the crack and fiberglass. 😮

This was SOOOO COOL

YES!

Pour the molten metal, not radially into the mold but 𝙩𝙖𝙣𝙜𝙚𝙣𝙩𝙞𝙖𝙡𝙡𝙮, so that, although the sloshing makes the liquid go further from or closer to the crucible, more melt will end up in the mold.

Thanks

Can always try ur hand at making a John Searl Generator. The one thing no one else has managed, is getting the eddy currents just right for the rollers for zero physical resistance.

Now that is WAY COOL!!!

7:55 You have made an induction motor. Thank you for sharing.

@eswnl1

2 ай бұрын

Just need a rotating magnetic field.

Never knew about this effect. Its really weird !! 🤯

Nondescript sheared copper wire is my favorite type of wild natural copper you can find in the suburban wilds.

Cool as hell

That's cool 😎 as heck

grate work casting, use steel wire to reinforce the mold it will help stop the cracking

Nice video! Thank you. Cool stuff for sure. Wondering what effect if any submerging the tube in a bucket of high metallic “mineral” water may have on the drop.