TRYMAG Small Rare Earth Magnets, Black, 400 Pcs, 3 Different Sizes, Tiny Mini for Crafts, Small Round Refrigerator Magnets for Miniatures, Refrigerator, Office, Kitchen, Cabinet

They’re smaller than what I first thought but that’s good, I didn’t want them to be so big. They’re VERY magnetic, hard to pull the magnets apart so that shows how good they are.

Hung a 32" steel decorative sign on a metal front door. Put all 100 of these on the back. It holds very well and gives the appearance that the sign was glued on without any damage to the paint

It wasn’t that strong and lost the power of attraction very quickly.

Works well but very tiny. Not sure what I was thinking.. wanted 7x1mm.

I picked up this 60-piece pack of TRYMAG Strong Rare Earth Magnets to use for latch mechanisms, modular component connectors, and removable panels on my 3D printing projects. Having previously tested various budget craft brands, I was specifically looking to see if these could maintain tight dimensional tolerances and a high-quality surface finish. They completely met my expectations. Why these magnets are a solid addition to a maker's hardware kit: Vibrant and Tough Nickel Coating: The triple-layer Ni+Cu+Ni coating on these discs is exceptionally clean and smooth. Budget magnets often arrive with minor chips or a flaky finish that compromises the surface contact, but these rolls are flawlessly plated, allowing mating 3D printed parts to sit completely flush against one another. Dependable Structural Pull: For their compact size, the magnetic force is highly impressive. They click together sharply and offer plenty of structural holding power to secure heavy printed enclosure doors, tool panels, or modular hobby displays without letting go under vibration. Uniform Sizing: I checked several of these randomly with a digital caliper, and they are highly uniform in both diameter and thickness. This consistency is absolutely critical when you are designing press-fit pockets in CAD, as a variance of even 0.1mm can result in cracked plastic layer lines or loose magnets that fall out. Makerspace & Engineering Tips: Perfect CAD Tolerances: When designing a socket or recess to hold these for a pure press-fit, aim to model your hole diameter roughly 0.1mm larger than the magnet's physical size. This provides just enough clearance to press them home securely using the flat side of a pair of pliers without splitting your printed walls. Securing with Adhesives: If your model has a bit of loose play, opt for a thick Cyanoacrylate (Super Glue) or a quick-cure 2-part epoxy. As a rule of thumb, avoid using a hot glue gun anywhere near neodymium material, as the high heat can instantly and permanently degrade the magnetic alignment fields. Check Your Polarization: Before permanently gluing matching pairs into your 3D assemblies, mark one side of the magnet stack with a marker. This ensures you don't accidentally embed a disc backward and end up with joints that actively repel each other. In the end, this TRYMAG set provides a fantastic balance of high-grade pull strength, dependable manufacturing tolerances, and pristine plating. They interact beautifully with rigid plastics and heat-set inserts, making them an excellent choice for any engineering or modeling workbench.