# Bearing Housing Or Seat Planning Skill

## When to use

- The request describes a bearing housing, bearing seat, bearing support, bearing block, pillow-block-like support, bushing seat, shaft support, or retainer body.
- The central functional feature is a precise coaxial bore, pocket, sleeve, shoulder, or counterbore that locates a bearing or bushing.
- The part is a single machined component that supports a shaft or bearing, not the rolling bearing assembly itself.

## Do not use when

- The user asks for a complete bearing with balls, rollers, cage, inner race, and outer race.
- The bearing word is only speculative and there is no bore, seat, sleeve, pocket, or retaining geometry.
- The part is mainly a flange, washer, simple tube, or rectangular plate with unrelated holes.
- The task requires an assembly of shaft, bearing, seals, fasteners, and housing together.

## Recognition features

- Coaxial shaft clearance bore through the body.
- Larger bearing pocket or counterbore with controlled depth.
- Shoulder, step, retaining lip, snap-ring groove, or cover seat to locate the bearing axially.
- Mounting base, side lugs, flange, bolt holes, ribs, or bosses can appear, but they support the bearing axis rather than define the part family.
- Chamfers at bore entrances and seat edges guide assembly.

## Core invariants

- Bearing seat diameter, shaft clearance diameter, housing outside diameter, and cover features share one axis.
- Separate the bearing outer-diameter seat from the shaft clearance bore; they are not the same feature.
- Leave a shoulder or defined depth when the bearing must stop axially.
- Build enough housing material before cutting the bearing pocket.
- Add mounting holes and ribs after the main bore/seat relationship is established.
- Do not model balls or rollers unless the prompt explicitly asks for a bearing assembly.

## Parameter roles

- `bearing_outer_diameter` defines the pocket or seat diameter.
- `shaft_clearance_diameter` defines the through bore.
- `seat_depth` defines how far the bearing is inserted.
- `shoulder_height` or `shoulder_diameter` defines axial retention.
- `housing_wall_thickness` controls material around the bearing pocket.
- `mounting_hole_pattern`, `base_length`, `base_width`, and `base_thickness` define attachment to the frame.
- `rib_thickness` and `rib_height` define optional support ribs.

## Construction sequence

1. Define the bearing axis and choose the housing form: block, flanged seat, sleeve, pedestal, or bracketed support.
2. Create the main housing/body with enough wall thickness around the bearing axis.
3. Cut the through shaft clearance bore on the main axis.
4. Cut the bearing pocket/counterbore to its seat depth, leaving a clear shoulder where needed.
5. Add retaining grooves, cover recesses, set-screw holes, oil holes, or alignment features only if requested.
6. Add base mounting holes, bolt pads, ribs, and bosses using datum-driven positions.
7. Finish with bore lead-in chamfers, outside chamfers, and small fillets.

## Common failures

- Generating a bearing assembly instead of a housing or seat part.
- Making the bearing seat and shaft clearance the same diameter.
- Missing the shoulder/depth that locates the bearing.
- Off-axis mounting of bore, pocket, or outer sleeve.
- Turning every bearing support into a flange even when the evidence suggests a block or pedestal.
- Adding decorative ribs or fasteners that obscure the bearing pocket.

## Evidence summary

- Current library evidence: 24 previously reviewed SCAD58 bearing housing/seat descriptions.
- Latest run evidence: accepted insights for central bore alignment, bearing/bushing-like cylindrical seats, coaxial features, counterbores, mounting holes, and chamfered bore entries.
- Frequent operations in the latest run: Extrusion, Revolution, Cut, RevCut, HoleWzd, Chamfer, Fillet.
- Source: CAD-SkillX offline review of SCAD58 descriptions, STEP summaries, and SolidWorks feature evidence.

## Retrieval metadata

Triggers:
- `bearing housing`
- `bearing seat`
- `bearing support`
- `bearing block`
- `bushing seat`

Secondary triggers:
- `bearing bore`
- `bearing pocket`
- `shaft clearance`
- `retaining shoulder`
- `coaxial seat`
- `pillow block`

Operation triggers:
- `cut coaxial bore`
- `counterbore bearing seat`
- `create shoulder`
- `add mounting base holes`
- `chamfer bore entry`

Exclusions:
- `complete rolling bearing`
- `plain washer`
- `flange only`
- `simple tube`
- `shaft only`