Gravity locked, print in place, vertical hinge

EDIT 2025/03/02 : Thanks to @DrLambda that helped with numerical analysis, the designed has been optimized for more stiffness.

The original “Very strong” profile has been deleted as this one is better

EDIT 2025/02/13  :  I've added a stronger version with tighter tolerances. (=> “Very strong version” print profile)

Hi !

I loved making this first print in place hinge and wondered what could the second version bring.

=> Gravity lock !

Concept :

This hinge is perfect for extending a table.

Once the hinge is in its contracted position, the geometry of the linkages locks the hinge in this position.

Once in this position, gravity keeps the hinge locked.

For the moment, the hinge sags a bit but I'm working on this.

I made a tool to help marking the  holes at the right position, you can find it here.

Slicing :

If you don't want to use my 3MF, don't forget to : 

• us adaptative layering, 
• use normal, snug, on build plate, supports

Printing :

Please calibrate your extrusion flow multiplier as printing in place demands a well calibrated printer.

Post-printing :

1. Remove the external supports

   

2. Firmly hold each part and separate them to break the system loose.

   It can be a little hard to break. Don't be shy and use all force needed.

   

3. Once you broke the system loose, there is 3 little internal supports to remove. (They should break once you play a little with the hinge)

   

Installing the hinge :

Use the tool to mark the position of the holes. Drill the hole to help guide the screw

First install the hinge on the “mobile” side. A hole allow the screwdriver to reach the screw

Then screw the other part to the fixed part of your furniture. You might need a second pair of hand.