1.1. Orienting Parts for Assemblies
Before making design alterations it is important to have a strategy for the build
orientation. Orientation of the mating components can affect the fit of the
assembly and will determine the necessary clearances.
To achieve the most accurate fit, it is critical to position all mating components
in the same manner relative to the XYZ axis (Figure 2). Choose an orientation
for the entire assembly and build all components in the same orientation, as if
they were assembled. Orient the mating surfaces in the X/Y plane whenever
possible. The X/Y plane is the most accurate plane and is thus the best plane
to orient critical mating surfaces.
Once the build orientation has been selected, the proper clearance can be
designed into the part. This can be accomplished with the use of 3D computer-aided design (CAD) software, STL editing software, or Insight™ software.
There are different clearance requirements based upon the FDM system and
the alignment of the assembly features in the build.
2.1. Assemble and Export the 3D CAD Model
STEP 1: Determine the orientation of the assembly.
STEP 2: Arrange components to create an assembly. Ensure the orientation
matches the desired build orientation (Figure 2).
NOTE: Ensure support material can be removed if using a break-away
STEP 3: Confirm individual part clearances are in accordance with the
information listed in Tables 1 and 2. Make any necessary changes.
NOTE: Use appropriate clearances (radial or diametrical) where appropriate.
STEP 4: Save all components of the assembly in a single STL file.
1) Check for interferences between parts.
2) Faceting can affect part-to-part clearances. For details, see the
Best Practice: CAD to STL.
3) Take note of the scale used when exporting. This will have to be
matched when importing into the Insight software.
2.2. Confirm Clearances
STEP 1: Configure the modeler.
NOTE: Import using the appropriate scale.
STEP 2: Open and orient the STL. Confirm that the assembly is oriented as
it was designed.
1) Do not scale a complete assembly in Insight software as this will also modify the clearances.
2) Do not rotate a complete assembly in Insight software (so that it is in different orientation than when it was designed) because the clearances were designed for a specific build axis.
STEP 3: Click to create part curves using the current parameters.
Click to create supports for the current job.
Click to create toolpaths.
STEP 6: Under the Toolpaths menu, select Shade toolpaths (Figure 3).
STEP 7: Right click anywhere in the viewport and select Snap-Measure
from the menu. Drag the cursor to measure the clearance between
model toolpaths (Figure 4).
STEP 8: Confirm that the clearances are in accordance with the clearances
listed in Table 3.
STEP 9: View the individual layer slices by clicking on the icon to view
the layers from the front.
STEP 10: Confirm that a support layer exists between model layers (Figure 5).
STEP 11: If the clearances and support layers are correct, proceed to step 12.
If the clearances are incorrect, modify the 3D CAD model
accordingly and repeat procedures 2.1. and 2.2.
STEP 12: Assemblies procedure complete.
3. TOOLS & SUPPLIES
• 3D CAD software
• Insight software (Document developed with Insight 9.0)