Switchable Magnet | Strength Test

https://youtu.be/9dUOA32Bdhw

The switchable magnets is the most satisfactory project I have built to date.


What makes it so special is the fact I used the Nikola Tesla handwritten notes, which I followed despite they didn't seem to follow the common logic or sense. And towards my great surprise, the switchable magnet works and it exceeded my expectations.


8 1 cubic centimeter NeoDymium magnets are the heart of this device, combined with 2 1 square centimeter profile iron bars, around 7 cm long, serving as a frame and the magnetic field loops conductor and amplifier.
The Nikola Tesla design is different from the most popular switchable magnets on the market, and the magnets arrangement is totally different, which is why it didn't make a scientific sense at first glance. Now I do fully understand how it works, and I take my hat off to the genius of Sir Nikola Tesla. His handwritten notes were a bit cryptic as well, but I'm happy to have figured them out, and after numerous prototypes and thorough testing, I found the best proportions and configuration, to achieve the best magnetic field amplification.


A single switchable magnet can lift up to 6 kg = 13.2 lbs. And it can withhold the force at 90 degrees on the steel surface (table saw / bandsaw / drill press) up to 6.7 kg = 15 lbs. Of course combining more switchable magnets will multiply the holding force capabilities.


In this video I demonstrate the real life test results, both of the lifting and 90 degree resistance to sliding on the steel surface.


I also listed quite a number of possible applications for this amazing tool.


Because it is fully made out of metal: aluminum, stainless steel, mild steel bars, neodymium magnets, these switchable magnets are welding friendly, which expands their functionality even further than just woodworking machinery assistance, such as jigs / fixtures / magnetic fences / feather boards / miter gauges / stop blocks / cut delimiters and whatever your imagination brings to your mind.


IF you don't have time or tools to make them, you can buy them off the shelf on:
https://tigertoolspro.com/product/sw...net-twin-pack/


Alternatively you can purchase the build plans in PDF exported from Sketchup, showing in details every angle, profile, dimensions, components used, assembly instructions and so on:
TigerToolsPro.com


The full build video is coming at the end of January 2022, so depending on when you are reading this description, it might be already available.


I truly enjoyed this project, as it brought limitless satisfaction to me.


I spent a lot of time and resources while prototyping this build and making the final product, so your purchase of the build plans is greatly appreciated.


Thank you so much for watching and your support!

I went to TigerToolsPro.com and searched for magnets but did not find anything.

Would you let me know when they are available?
The magnets and the .PDF.
Ralph

Thanks for your interest in the switchable magnets.

I've added the switchable magnets to the TigerToolsPro.com
https://tigertoolspro.com/product/sw...net-twin-pack/

I've just released the Strength Test video, and now editing the Full Build video, which will be released in 3rd week of Jan 2022.

I'll add the build plans to TigerToolsPro.com website by 16 Jan 2022, as I need to edit them to reflect the final dimensions and changes to the last prototype. They will be USD9.99 until June 2022, and then USD19.99

You should be able to build it by just watching the upcoming build video, but the plans purchases are welcome to support my research and help me cover my expenses on the tools and materials.

Please subscribe to Tiger Carpenter on YouTube and you will be notified when the build video is published.

Cheers!

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Thanks tiger carpenter! We've added your Switchable Magnets to our Miscellaneous category,
as well as to your builder page: tiger carpenter's Homemade Tools. Your receipt:

<div id="blocks"> <div class="block b1 pngfix"> <div class="bimg"> <div> <a href="https://www.homemadetools.net/homemade-switchable-magnets"> <img src="/uploads/253000/homemade-switchable-magnets.jpeg"/> </a> </div> </div> <div class="head pngfix"></div> <div class="left pngfix"></div> <div class="right pngfix"></div> <div class="blockover b1 pngfix"> <div class="title"> <a href="https://www.homemadetools.net/homemade-switchable-magnets">Switchable Magnets</a> <span> by <a href="https://www.homemadetools.net/builder/tiger+carpenter">tiger carpenter</a></span> </div> <div class="tags">tags: <a href='https://www.homemadetools.net/tag/magnet'>magnet</a> </div> </div> </div> </div>
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I've just added the Switchable Magnet Build Plans:
https://tigertoolspro.com/product/sw...t-build-plans/

The claim about multiplication of the magnetic flux makes this worth looking into and I like the addition of sandpaper. Also, according to Pierson Workholding.com the sandpaper (friction) greatly improves lateral holding force exponentially! (I have zero affiliation with anyone)

Tiger's website appears to be a work-in-progress. Very nicely done but the link to the privacy policy (on the shopping cart check out page) is broken. He is straight forward about privacy so I assume it is a small detail that will get fixed soon. 99% of online users don't care (or read) the policy so I am posting this for the 1%ers. :)

Note to admin: I could not insert the link to the bold italic text above without it displaying in full screen mode taking over this entire post so I have unlinked it. The part about sandpaper appears at 3:37 in one of the vacuum-plate videos. It is good information for those interested in a holding technique requiring friction. The Pierson link works fine. The difference is the 2nd link was a video and I copied the URL at the time point in the video to save viewers from scrolling through the whole thing and maybe missing the important part.

Thanks for your comments!
I measured the sandpaper gains of the lateral holding force, and it was only 15% improvement, so it's not exponential but worth doing anyway.

I think if we measured the forces while dragging, the friction = lateral holding force gains would be bigger (again not exponentially but few times, especially when comparing the slippery hockey ice platform like sliding on the skates to walking on ice with good grip shoes), but we are after that borderline / initial movement moment after which the magnet or fence moves. Once it moves, we consider it as a failure, because the accuracy of the cut depends on the immobilised setup.

So the sandpaper gave me 15% improvement, which is fair enough but I admit I was hoping it would be more than that.

PS
I will make an update video, when I add the sandpaper to the whole length of the magnetic fence's base (under the aluminum extrusion). Definitely it will help, but let's not be overly optimistic to avoid disappointment.

Quote:

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Originally Posted by Ralphxyz

I went to TigerToolsPro.com and searched for magnets but did not find anything.

Would you let me know when they are available?
The magnets and the .PDF.
Ralph

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K & J magnets will probably have them.

I've added the Switchable Magnets to the TigerToolsPro.com
https://tigertoolspro.com/product/sw...net-twin-pack/

I've added the Switchable Magnet Build Plans to the TigerToolsPro.com
https://tigertoolspro.com/product/sw...t-build-plans/

Nobody else will sell them because I designed them from scratch and I manufacture them as well.

I'm not sure but doesn't magnetism decrease as the square of the distance? 1 mm thick sandpaper will lower your magnetic strength compared to metal-to-metal contact. But since you found increased force with added friction it is certainly worth it. The link I referenced was about increasing the lateral holding force of a vacuum plate. Basically, reacting the lateral force when milling with an vertical end mill. Since the vacuum plate is using atmospheric pressure x area, the force will not change by adding some frictional thickness under it. Again, I'm not sure but maybe Pierson's vacuum tests produced a stronger force than you experienced with magnetism. I agree, "exponential" is a very strong word to be using but the test parameters are also totally different. Doesn't friction increase with weight or force? There may be a point using vacuum plate that area can increase to such a point we might be seeing exponential values.

I tried to edit my post above again, to provide a direct link to the vacuum plate suggestion. I will put it in a separate post.

This video has suggestions on improving vacuum plate holding force on a milling machine. My apologies, I have worked on this for an hour to try and provide a cleaner way to get to the information. I am only offering this as support information on the use of sandpaper.

Go to 3:33

here:

300 grit waterproof abrasive sheet is 0.1 mm thick (I've just measured it) + ~0.03 mm glue (maybe)

Adding the sandpaper increased the holding force by 15%, which means it was the right move (for the lateral applications mostly in woodworking). For welding applications, you can remove the 0.13 mm sandpaper to gain that "little" extra of magnetic flux.

Obviously the magnetic field weakens when we increase the distance, but it is insignificant in this case.

Quote:

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Originally Posted by Saltfever

edit . . . Tiger's website appears to be a work-in-progress . . . link to the privacy policy (on the shopping cart check out page) is broken.

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The broken link is fixed. Much better than others and nicely done. Very easy to read.

Thanks for pointing the broken links.

In fact the pages were ready long ago but saved as Draft, and I didn't realise they weren't published. Thanks again for your help!

Damm!! I just ordered the magnets and the .pdf. Then I saw the shipping $99.00 I di not see the shipping until I had ordered.

Please CANCEL the order! I do not know how else to cancel the order.

Ralph

Quote:

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Originally Posted by Ralphxyz

edit . . . I do not know how else to cancel the order.Ralph

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You might try contacting him here:

info[at]tigertoolspro.com

It is listed in the "Refunds and returns" description.

He came through with a much better shipping price! I just received the magnets today. I am not particularity impressed the the magnets holding power.
They are rather easy to move with the magnet(s) engaged, if you just bump them they move.

Ralph

I'm glad the magnets reached you so fast.

I clearly demonstrated the magnets strength both when the vertical and horizontal forces were applied, and it is around 6kg = 13.5 lbs per magnet.
It works perfectly well in woodworking applications such as magnetic fences or jig holders. It also works fine for welding jobs to align the parts at the right angle.

I don't like to talk bad about the competition but since you brought this topic, if you are familiar with MagSwitch 150 which claims cosmic magnets breakaway point at 150 lbs = 68 kg, and they can't even hold the featherboard on the table saw.

The bumping force that is capable of moving my magnets must be bigger than 6 kg per magnet. In my video I showed how hard it is to move my magnets with the scale, in the so called typical use, where you don't knock them abruptly.

I will buy the MagSwitch and make a comparison video side by side to clear the waters around MagSwitch strength.

PS
Please add info[at]tigertoolspro.com to your contacts, as Gmail is blocking all of our communication. Even though my email is a reply to your email, it still says it is unsolicited email. There goes Alphabet monopolistic practices, trying to suppress every small business.
I emailed you the Build Plans (which most customers download using the link you are redirected to upon completing the payment) several times from various email addresses, and your Gmail seems so paranoid that it blocks all the emails sent to you.
Please look in your Spam folder, and update me if you found all my old emails, or Gmail blocked them and didn't even Spam them.

Thanks, I have MagSwitch magnets so one of these days I might get around to comparing them.

Ralph

Please share the comparison results. I'm also interested whether MagSwitch can withhold 150lbs as they claim. We both know the answer, but it would be interesting to actually measure their puppies.

I use the Magswitch magnets on a fence for my bandsaw, they hold really good.
I just played with your magnets for a couple of minutes not doing any work just lifting and pushing them around.
So I will have to work with them to really judge the holding strength and to compare them with Magswitch.

Ralph

Ralph:
The holding power of a magnet is affected by many variables. Anything less than optimum and the loss of holding power is significant! The picture is the chart attached to my 800lb lifting magnet. Note, the thickness of the steel and the air gap are significant! What is not pictured is how material properties also affect holding power. Carbon steel has the highest power and some of the stainless steels are lowest. Cast iron is not as good as steel. If you are comparing magnets be sure all variables are the same for each. For example, your band saw table is likely a precision ground cast iron surface. The grind, or surface finish, has a big effect on magnetism. Be sure to compare the magnets in the same way.

Attachment 41624

Deleted. Question already answered.

I just remembered I do have a pull scale somewhere in my shop so I could do some measurements if I find it.

Ralph