Grabby, the watch stand

A stand for a single wristwatch or smartwatch that automatically grabs the watch using its own weight and holds it regardless of the type of bracelet or strap used. The main idea is that you don't have to mess with the strap, fasten it around anything etc., just lift the tray, the paws will spread, place the watch on the tray a let the tray slide down, closing the paws and grabbing the watch. 

Print instructions

Assembly video and function demo:
 

Besides the printed parts, you will need:

90pcs 4mm loose ball bearings (87 to be exact)

2pcs M5x20mm allen head bolts
(I recommend one regular DIN 912 and one button head ISO 7380)

optionally 2pcs M5 washers (DIN 125 5.3x10x1mm)

About the pritned parts:

Only the upper paw needs supports (under the long straight part), the rest should be fine without supports (the upper tray is printed upside down, the rest "as is" - see the picture)

The grooves for ball bearings printed upside down may need a bit of cleanup after printing (or supports in the worst case)

For the threaded parts (Base and Tray upper), you can choose either the variant with a modelled thread ("_thread") and try to print it in place, or the variant with a 4mm hole ("_hole") and tap it to M5

The paws are provided in three sizes of the gap between the paws and the tray (3, 5 and 7mm), you can choose depending on the thickness of your strap (or if you want to glue some padding/gripping material to the paws...)

The bottom paw is provided in both signed and unsigned versions

When printing the base, you can pause the print (e.g. using the color change option in PrusaSlicer) before the bottom platform is closed on the top and fill the base with sand or something to make it heavier (make sure to use an infill pattern that is open from the top, like rectilinear)

Successfully tested – it works!