Parametric cat clamp hook

A slim, flat-printed hook that clips over any shelf edge, counter rim, sink divider, or raised rail — no drilling, no adhesive. A stretching cat silhouette rides the clamp gap, visible from both sides once installed.

How it works

The hook has five straight segments that form a C-clamp profile. Two segments (L1 and L2) grip the rim from behind and from the front; L3, L4, and L5 extend below as the hanging arm. Because every length is a parameter you set before printing, one file fits almost any rim.

Sizing guide — measure these three things first

What to measure	Maps to
Depth of the recess behind the rim (how far back the hook reaches)	L1
Thickness of the rim itself (face-to-face)	L2 base value
How far below the rim you want the hook arm to extend	L4

L1 and L2 are both inner (clear) dimensions — set them to your actual measured values and add 0.5–1 mm clearance. You do not need to compensate for wall thickness; the Customizer handles that automatically.

Quick start with defaults (L1 = 15, L2 = 20):

Fits a rim up to 20 mm thick with a 15 mm back recess.
Prints flat at roughly 40 × 54 × 4 mm. No supports needed.

All parameters

Hook geometry

Parameter	Basis	Description	Default
L1	INNER	Back arm clear — set to the recess depth behind your rim	15 mm
L2	INNER	Clamp gap — set to rim thickness + 0.5–1 mm clearance	20 mm
L3	OUTER	Hook drop below rim (must be > L1 + 2 × wire_d)	40 mm
L4	OUTER	Hook arm that extends outward	30 mm
L5	OUTER	Hook tip — points upward to retain hung items	20 mm
wire_d	—	Ribbon width of the flat wire profile	4 mm
plate_d	—	Extrusion height (print thickness)	4 mm

Constraint: L3 must be greater than L1 + 2 × wire_d or the hook gap closes. With defaults, that minimum is 23 mm; the default L3 of 40 mm gives a 17 mm opening.

Cat motif

Parameter	Description	Default
cat_width_mm	Head-to-tail length of the cat in the mounted orientation. Keep ≤ L2 to fit within the clamp gap.	16 mm
cat_lift_mm	Gap between the wire and the cat's base, revealing the paw/belly silhouette. Exceeding wire_d/2 fully disconnects the cat.	1.0 mm
cat_line_extra_mm	Extra outline thickness per side — increase if the line art looks too thin after printing	0.5 mm
mirror_cat	Flip which side the body bulges toward	false
show_cat	Show or hide the cat motif entirely	true

Print settings

	Recommended
Orientation	Flat on bed (XY plane) — no rotation needed
Supports	None required
Layer height	0.1–0.2 mm
Perimeters	3 or more for a clean cat outline
Infill	40 %+ for grip strength
Material	PLA, PETG, or ABS — anything stiff enough to hold the rim
Print time	~20 min at 0.2 mm layer height (default size)

Tips

Tight fit vs. easy removal: Set L2 = rim thickness + 0.5 mm for a snug grip, or + 1.0 mm if you want to slide it on and off frequently.
Heavier loads: Increase wire_d (try 5–6 mm) and plate_d (try 5 mm) for a beefier cross-section.
Cat too faint after printing? Increase cat_line_extra_mm to 0.8–1.0 mm.
Two-color printing: Pause at layer 1 and swap filament to make the cat silhouette a different color from the hook body.
No cat: Set show_cat = false and you get a clean minimal clamp hook.

Files

File	Description
cat_clamp_hook_v2.scad	Fully parametric OpenSCAD source — open in MakerWorld Customizer

Artwork: stretching cat line illustration vectorized via Inkscape, simplified to 153 points (Douglas-Peucker tol 1.2) and embedded directly in the SCAD file — no external SVG dependency.