Printing 3D Parts

Hello,
I need your helps.Can you advice infill rate? I want it to be solid.
Bonjour,
J’ai besoin de vos aides. Pouvez-vous conseiller le taux de remplissage? Je veux que ce soit solide.

Hey

I printed all the parts for Ergo Jr at not more than 35%, apart from the bolt on the pen holder, I made that 50%. Seems strong enough

Ian