I purchased magnets from Amazon to hold down warped plywood in my laser engraver and the tops were too tall, but without them it was difficult to lift and position the magnets. This design allows you to leave the magnet flat on the honeycomb bed without having to angle it losing contact surface area. The 1/8 in material hold down has a 3mm gap to give a snug fit and the ¼ inch material hold down has a 6mm gap. The 1/8 did work on ¼ material with a slight angle / tilt. The magnets I used are shown in the photos and I'll include the link. The photo is incase the link for some reason no longer works.

the magnets I ordered are the 100lb magnets and the nuts I used are 8-32 nuts

Amazon link: https://www.amazon.com/dp/B08VD2W2G4?psc=1&ref=ppx_yo2ov_dt_b_product_details

Since not everyone has a printer, if someone wants these, feel free to print them for others. I only ask you charge only materials and time and not sell these in an etsy or similar store.

If you feel so inclined, buy me a coffee : Coffee