FINDMAG 100Pcs Strong Neodymium Magnets Bar, Heavy Duty Rare Earth Magnets, Rectangular Magnetic Bar, Small Powerful Magnetic Bar for Crafts Kitchen DIY Tool Storage Science Office – 10x5x2mm

These are the magnets that I got: https://www.amazon.com/dp/B0B6PBXBVJ?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_2 and the core is just regular 3d printed petg. I would understand if this was an issue about the core itself, but I can't figure out why the video i linked works all good since I am pretty sure a 3d printed core is also what he uses without any special material. I am not convinced it's the material tho. That's cuz when i bring the stator core near magnets I can feel it vibrating and there's like a clear increase in vibration as I increase the amperage.

https://a.co/d/0cD5rHo0 Just stacked a couple of these. Still holds strong with some epoxy