Are escape holes obligatory? (polyamide MJF)

For powder printing in polyamide (MJF) it is recommended to hollow out my 3D model and put escape holes in the model. I’ve hollowed out the model but escape holes would mess with my design. So can I omit the escape holes and just leave the excess powder inside the model?

The model exists of four quarters of a sphere (6 cm in diameter).


Escape holes are required for hollow parts produced with MJF. In case adding holes is not an option for your design, then we recommend 3D printing it solid.

Hi Dmitri,

Thank you for your advice.
Indeed, clearance holes are not an option for my design so I’ll exclude them and leave my object solid.

There is maybe an option for clearance holes but I don’t know if it will suffice.
At the hinges there is a clearance of 0.5 mm. I can connect this clearance with
the hollow inside of the model. At the other side there are holes with a diameter of 5.3 mm that also can be connected with the hollow inside. The connections are straight, so no ducts. This is much smaller then your recommended size of clearance holes so I think I already know your advice :wink:
Also, I think it isn’t worth the trouble nor the price difference between hollow and solid (I’ll have to check)…