# How would you design a bookmark using rare earth magnets? **URL:** \ **Category:** Factual Questions\ **Created:** [July 19, 2008, 9:26pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090 "2008-07-19T21:26:13Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![BarnOwl](https://avatars.discourse-cdn.com/v4/letter/b/e95f7d/32.png) [@BarnOwl](https://boards.straightdope.com/u/BarnOwl)\ **Post date:** [July 19, 2008, 9:26pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090/1 "2008-07-19T21:26:13Z")
What inspired the question: I saw this woman in a doctor’s office. She used a clip like this: > **[Amazon.com: Binder Clip, Steel, Assorted Sizes (Mini, Small, Medium),...](https://www.amazon.com/Binder-Assorted-Medium-Silvertone-CEB35062/dp/B000TGTF3I)** > > Reusable tub includes: 12 Mini, 6 Medium and 12 Small Binder Clips. Tempered-Steel clip handles fold flat for storage, flip up for easy hanging, easily removed for binding. Perfect for business presentations. Silvertone To hold her place in a paperback book she was reading. She turned out to be a wonderful person to talk to and explained how this innovation of hers enables her to read with just one hand on the book, but also to mark her place when she puts it down. So, I have similar clips and tried them with a Crossword Puzzle book, and another for a Bonsai book. Both are paperbacks. But they (the books) are so thick that the clips won’t work when I get deeper into the books. So, I’d like to see what could be done with neodymium magnets like those at… > **[Strong rare earth neodymium magnets | K&J Magnetics](https://www.kjmagnetics.com/)** > > Vast selection of super strong permanent rare earth neodymium magnets at low prices. Huge stock, fast shipping, great customer support. …et al. Why those magnets? You can get very strong neodymium for relatively cheap. And it might be a fun project. I’m aware of the pitfalls and dangers of these things, so I’d be very careful. Any ideas? ---
**Author:** ![Tastes\_of\_Chocolate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tastes_of_chocolate/32/3232_2.png) [@Tastes\_of\_Chocolate](https://boards.straightdope.com/u/Tastes_of_Chocolate)\ **Post date:** [July 21, 2008, 4:39pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090/2 "2008-07-21T16:39:30Z")
We have a couple of magnetic book marks. They are 2" by 4" pc of paper, folded so each side is 2x2" Then one side has a piece of metal and the other has a magnet on it. Looks kind of like a matchbook cover. Maybe a variant on that? You’d want to have the magnet on the outside and the metal on the inside, or you won’t be able to close your book. ---
**Author:** ![BarnOwl](https://avatars.discourse-cdn.com/v4/letter/b/e95f7d/32.png) [@BarnOwl](https://boards.straightdope.com/u/BarnOwl)\ **Post date:** [July 21, 2008, 6:26pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090/3 "2008-07-21T18:26:12Z")
[QUOTE=Tastes of Chocolate] We have a couple of magnetic book marks. They are 2" by 4" pc of paper, folded so each side is 2x2" Then one side has a piece of metal and the other has a magnet on it. Looks kind of like a matchbook cover. Maybe a variant on that? You’d want to have the magnet on the outside and the metal on the inside, or you won’t be able to close your book. [/QUOTE] Very good idea!!! Thanks a lot **Tastes of Chocolate** , I’ll use it. If I may ask… Do you use strong neodymiums? If so, could you recommend the one you use? ---
**Author:** ![jayjay](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jayjay/32/6765_2.png) [@jayjay](https://boards.straightdope.com/u/jayjay)\ **Post date:** [July 21, 2008, 6:56pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090/4 "2008-07-21T18:56:32Z")
You could also use the design that I’ve seen for weighted bookmarks…a long strip of leather/cloth with weights or magnets sewn inside. The weighted version would just sit on the open book, holding the pages down. The magnet version could be made with a “bridge” roughly 3" long, which should span at least half the pages of any normal-size novel. It’s basically just two larger ends with the magnets sewn inside (though how you’d use a metal needle anywhere near a rare earth magnet, I have no idea, now that I think of it), connected by a bridge or strip of the same material. ---
**Author:** ![BarnOwl](https://avatars.discourse-cdn.com/v4/letter/b/e95f7d/32.png) [@BarnOwl](https://boards.straightdope.com/u/BarnOwl)\ **Post date:** [July 21, 2008, 7:51pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090/5 "2008-07-21T19:51:54Z")
[QUOTE=jayjay] You could also use the design that I’ve seen for weighted bookmarks…a long strip of leather/cloth with weights or magnets sewn inside. The weighted version would just sit on the open book, holding the pages down. The magnet version could be made with a “bridge” roughly 3" long, which should span at least half the pages of any normal-size novel. It’s basically just two larger ends with the magnets sewn inside (though how you’d use a metal needle anywhere near a rare earth magnet, I have no idea, now that I think of it), connected by a bridge or strip of the same material. [/QUOTE] Maybe I shouldn’t use rare earth magnets at all. Here are just some of the caveats from: > **[Neodymium Magnet Safety | K&J Magnetics](https://www.kjmagnetics.com/neodymium-magnet-safety.asp)** > > How to stay safe when handling neodymium magnets and how to prevent damage to your magnets. The strong magnetic fields of neodymium magnets can also damage magnetic media such as floppy disks, credit cards, magnetic I.D. cards, cassette tapes, video tapes or other such devices. They can also damage televisions, VCRs, computer monitors and other CRT displays. Never place neodymium magnets near electronic appliances. Children should not be allowed to handle neodymium magnets as they can be dangerous. Small magnets pose a choking hazard and should never be swallowed or inserted into any part of the body. Never allow neodymium magnets near a person with a pacemaker or similar medical aid. The strong magnetic fields of the magnet can affect the operation of such devices. They could probably damage my wrist watch, as well (much less someone’s pacemaker!!). ---
**Author:** ![Tastes\_of\_Chocolate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tastes_of_chocolate/32/3232_2.png) [@Tastes\_of\_Chocolate](https://boards.straightdope.com/u/Tastes_of_Chocolate)\ **Post date:** [July 21, 2008, 10:09pm UTC](https://boards.straightdope.com/t/how-would-you-design-a-bookmark-using-rare-earth-magnets/457090/6 "2008-07-21T22:09:54Z")
[QUOTE=BarnOwl] If I may ask… Do you use strong neodymiums? If so, could you recommend the one you use? [/QUOTE] Actually, I’ve never made one. We have a couple that my MIL brought back from a vacation. They have touristy pictures on the outsides. These aren’t nearly as strong as you are looking at. They will hold the bookmark through a handfull of pages, which keeps the bookmark from falling out of the book, but not from the cover to the center, like you seem to be looking for.