Sphere Magnets: Easy to Handle, High Pinning/Holding Power
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Sphere magnets work best for holding/pinning things with significant thickness in place. That’s because their point force is very high, which compresses the material and allows for a much stronger grip for the same rated holding power versus a cylinder or block magnet, which will have a much larger surface area, and thus might not be able to anchor itself as close to the underlying steel, since the material won’t compress as much.
Size and holding power
For sphere magnets, go no smaller than 3/4-inch diameter, which work very well, but are still a bit small for my fingers. Still, the 3/4" size is very cost effective with high holding power.
Exception: 1/4", 3/8", 1/2" magnets (many of them) can be used to pin light fabric or curtains along a wall. These can be gold or nickel or black, and might be desirable for decorative effect. They can also be used in rings or chains for fun purposes.
For peak holding power, choose 1-inch diameter N52-grade sphere magnets. These are extremely powerful and with a much better grip. Even so it is difficult to separate two N52-grade 1-inch sphere magnets; put a piece of 3/16" foam between them when storing, or similar. Consider also putting a small piece of gaffer’s tape @AMAZON on each pole for a bit of cushioning when attaching directly to metal.
For example as shown below, a sphere magnet easily flattens the air bubbles in the Reflectix for powerful contact with the sheet metal of the van (it wll be a shame if Mercedes ever switches to an aluminum hull).
Magnets holding on exterior shade panels
Over the windshield, four one-inch grade N52 nickel-coated sphere magnets from KJMagnetics.com hold the Reflectix @AMAZON in place, even with moderate wind so long as the material is snugly stretched (so it cannot become a sail). For the side panel only 3 magnets are shown; use four if windy.
Use great care in handling these magnets, such as when taking the shade off. I recommend emptying pockets so that a single magnet can go into each pocket prior to storage. If allowed to snap together hard, they almost certainly will shatter, which can be a huge mess if any steel is nearby. Consider wrapping them fully in gaffer’s tape, or at least covering the pole areas for a little cushioning.
Choose high quality N52 grade 1-inch sphere magnets for powerful “pinning” purposes because the pulling force is needed to keep the Reflectix in place and without movement (which would scratch the paint). Moderate-strength magnets are no good—even a mild wind will drag them around and maybe rip the shield off entirely.
Below, N52-grade 1-inch sphere magnet holds the Reflectix @AMAZON in place.
Tip: put a small piece of bright green gaffer’s tape on the Reflectix in order to place the magnet the same place each time, once the best position is found.