5x2mm Disc Magnet Hole Tester

thingiverse

I'm testing a small block with varying hole sizes to determine the optimal size for my disc magnet models, ensuring a secure fit when printed. I'm currently using 5x2 mm magnets but can easily adjust the CAD model on Onshape: https://cad.onshape.com/documents/6b3954c6c5ec6e5c690a5d29/w/59b4fd7f81be094b582ee74b/e/1e8a4d3f75e408a6198c0d83. I've made the block thicker than necessary to accommodate warping, and it has holes with different diameters (+0.1mm, +0.2mm, +0.3mm, +0.4mm). The magnet hole depths are all 2.2mm, with an additional 0.2mm for flush mounting. With a 0.2mm layer height print and the holes on top, I find that magnets fit snugly in the +0.3mm holes but can be forced into those with smaller diameters. However, flipping the model so it's printed with the holes on the side yields different results: magnets must be forced into all holes, and may not even fit into the 0.1mm hole. In conclusion, I've found that a magnet width of +0.3mm provides a secure, snug fit for both top and side holes. Using Loctite 401 should ensure a strong bond between the magnet and block.