Mechanical structure and force loop
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Frame and primary structure
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- Welded steel box-section construction
- Two rectangular frames:

  - lower frame
  - upper frame
- Frames connected by four vertical steel legs
- Box sections sized for stiffness via geometry, not mass
- Welding limited to areas where deformation is acceptable

Frame bracing
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- Steel tension members used for frame bracing
- Implementation:

  - threaded steel rods
  - or steel tubes with internal threads
- Bracing applied on both diagonals
- Members preloaded to pull frame into square
- Bracing is:

  - non-moving
  - serviceable
  - not part of damping strategy

X gantry structure
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- Two parallel horizontal box-section beams
- Beams span the upper frame
- Beams support:

  - spindle tower
  - X-axis motion
- Beams connected to linear bearing blocks on upper frame rails
- Beam spacing sized to accommodate:

  - spindle plate
  - Z-axis rails
  - spindle housing

Spindle tower
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- Constructed from steel plates (approx. 10 mm thickness)
- Plates bolted together (not welded)
- Alignment procedure:

  - tower aligned perpendicular to table
  - fasteners torqued
  - holes drilled and reamed
  - dowel pins inserted to fix alignment
- Tower rigidly connects spindle plate to X gantry beams

Force loop definition
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- Explicit force path during cutting:

  - tool
  - spindle
  - spindle housing
  - spindle mounting plate
  - spindle tower
  - X gantry beams
  - frame
- Structural elements outside this loop are not considered load-bearing

Table and Y-axis support
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- Steel table plate (approx. 10-15 mm thickness)
- Four linear bearing blocks mounted under table
- Bearing blocks positioned near table corners
- Primary loading of bearing blocks in Z direction
- Two Y-axis rail support beams:

  - bolted to lower frame
  - parallel to frame sides
- Rail support beams are removable and alignable

Optional table stiffening
-------------------------

- Shallow steel ribs or profiles may be added under table plate
- Attachment method:

  - adhesive bonding
  - bolting
- No welding to table plate