Pétanque/Boules Jack

This is a Pétanque Jack that prints in two halves, to ensure it prints cleanly without supports on an FDM printer.  No extra hardware or glue is required - the two halves screw together using the printed stud.

The jack is the regulation 30mm in diameter, and if printed with 100% infill it will print with the regulation weight of between 10g and 18g (PLA/PETG comes out at ~15g, ABS ~12g).

Just don't print it in Grass Green if you're planning to play in a campsite field ;)  I created this model to replace such a green jack that was lost in the grass.

Print Settings

Print the stud with a layer height of 0.2mm, and the jack halves with 0.2mm up to a height of 10mm, then 0.1mm for the top 5mm to minimise the steps between layers where the hemisphere flattens at the top.  A 5mm brim for the stud will prevent it from falling over during a fast IS print - give the brim a 0.2mm separation gap to make it easy to remove.

I have included a 3MF file that includes these settings.  I have reduced the filament ‘Extrusion multiplier’ to 0.9 to ensure there are no problems with the 100% infill.

The top surface of the female thread in the jack half will bridge quite easily without supports, and the thread is deep enough that a small amount of filament sagging will not prevent the stud from screwing in far enough.

I have also included the OpenSCAD script that I used to produce this model.  It uses Ryan Colyer's OpenSCAD ‘Threads’ module.