This is a small hold down clamp I design from a photo, used for clamping material down to my cnc router, need a low profile clamp for clearance.

Print all parts, I use small pieces of filament for the joints, you might have to clean the holes up with a small drill for the filament to slide in, cut the pieces of filament a little longer than needed, then take a solder iron to melt the ends. print with whatever material you like, I use glass reinforced PETG and they are strong. I use a 8-32 screw with for the hold down end with nut and wing nut for adjustment. as shown in image,

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