Final Considerations Before Printing
Before printing, it is important to examine the wall thickness throughout the core for consistency & correction, ensuring there are no entrapped supports.
Other recommended inspection tools:
- GOM Inspect: used to validate that you uniform/desire wall thicknesses in your part
- Synopsys or Ansys Additive: used to check for build errors, discretion, etc.
Post-Processing Considerations
- Surface finishing processes of the internal core can remove a substantial amount of material — understand how much your post-processing removes so that you can add stock material to the digital model
- Powder-removal considerations: Two primary considerations regarding powder are
- Time/Ease of removal
- Permanently entrapped regions
- Wire EDMwon’t interfere with the powder. This will help preserve the wire’s longevity and cleaning process.
- Planning with these and other powder considerations in mind during the design process can go a long way. Often if we are designing for fluid flow, the powder may ‘naturally’ drain out. We can also add turrets/drain holes at the structure’s base or the Inlet/Outlet ports. See Image 1 below.
Image 1: A designed and printed heat exchanger with ‘drain turrets’ at the base. These drain ports allowed for the majority of the powder to ‘naturally’ drain before the wire EDM removed the part from the build plate.
- Internal support removal
- A common technique would be to utilize the AFM, solvent, or slurry we use for surface finishing. This technique often removes ‘x’ amount of material from the walls. If you make the contact point between the support and the structure less than ‘x,’ the support will dislodge.
- Be mindful that the support structures have a route out of the heat exchanger. Know the weight of the support structure as designed and weigh what is extracted to ensure it is removed.
- External support removal
- While external support removal is often less technically challenging than internal, consider the process and adjust geometry as needed.