A metal weldment consisting of a counterdrilled plate, a centrally mounted housing tube, and four structural support fins.

// Counterdrilled Weldment
// A metal weldment consisting of a counterdrilled plate, a centrally mounted housing tube, and four structural support fins.
// Categories: Manufacturing, Construction

// Set units
@settings(defaultLengthUnit = in)

// Define parameters
boltSpacingX = 5
boltSpacingY = 3
boltDiameter = 1 / 4
counterdrillDiameter = 7 / 16
counterdrillDepth = 3 / 16
tubeInnerDiameter = 1 + 1 / 4
tubeThickness = 0.115
tubeHeight = 2
stockThickness = .5

// Calculate the dimensions of the block using the specified bolt spacing. The size of the block can be defined by adding a multiple of the counterdrill diameter to the bolt spacing
blockLength = boltSpacingX + boltDiameter * 6
blockWidth = boltSpacingY + boltDiameter * 6

// Draw the base plate
plateSketch = startSketchOn(XY)
  |> startProfile(at = [-blockLength / 2, -blockWidth / 2])
  |> angledLine(angle = 0, length = blockLength, tag = $rectangleSegmentA001)
  |> angledLine(angle = segAng(rectangleSegmentA001) + 90, length = blockWidth, tag = $rectangleSegmentB001)
  |> angledLine(angle = segAng(rectangleSegmentA001), length = -segLen(rectangleSegmentA001), tag = $rectangleSegmentC001)
  |> line(endAbsolute = [profileStartX(%), profileStartY(%)], tag = $rectangleSegmentD001)
  |> close()
  |> subtract2d(tool = circle(center = [0, 0], radius = tubeInnerDiameter / 2))

// Define hole positions (face-local: note X/Y swapped vs world XY)
holePositionsSwapped = [
  [-boltSpacingY / 2, -boltSpacingX / 2],
  [-boltSpacingY / 2, boltSpacingX / 2],
  [boltSpacingY / 2, -boltSpacingX / 2],
  [boltSpacingY / 2, boltSpacingX / 2]
]

// 1) Extrude plate
plateTopExtrude = extrude(plateSketch, length = stockThickness, tagEnd = $plateTop)

// 2) Chamfer perimeter (separate from extrude)
plateChamfered = chamfer(
  plateTopExtrude,
  length = boltDiameter * 2,
  tags = [
    getNextAdjacentEdge(rectangleSegmentB001),
    getNextAdjacentEdge(rectangleSegmentA001),
    getNextAdjacentEdge(rectangleSegmentC001),
    getNextAdjacentEdge(rectangleSegmentD001)
  ],
)

// 3) Hole pattern (separate statement for readability)
plate = hole::holes(
  plateChamfered,
  face = plateTop,
  cutsAt = holePositionsSwapped,
  holeBottom = hole::flat(),
  holeBody = hole::blind(depth = stockThickness, diameter = boltDiameter),
  holeType = hole::counterbore(diameter = counterdrillDiameter, depth = counterdrillDepth),
)

// Drill a small pin hole in the side of the tube (separate extrude)
pinholeSketch = startSketchOn(YZ)
  |> circle(center = [0, 2.2], radius = 0.125)
pinhole = extrude(pinholeSketch, length = -10)

// Model the central tube and subtract the pin hole (separate extrude)
centralTubeSketch = startSketchOn(offsetPlane(XY, offset = stockThickness))
  |> circle(center = [0, 0], radius = tubeInnerDiameter / 2 + tubeThickness)
  |> subtract2d(tool = circle(center = [0, 0], radius = tubeInnerDiameter / 2))
centralTubeSolid = extrude(centralTubeSketch, length = tubeHeight)
centralTube = subtract([centralTubeSolid], tools = [pinhole])

// Inline fins (no extrude piping)
// Diagonal plane helper for i = 1
finDiagPlane1 = {
  origin = [0.0, 0.0, 0.0],
  xAxis = [
    boltSpacingX / 2 * 1,
    boltSpacingY / 2,
    0.0
  ],
  yAxis = [0.0, 0.0, 1.0]
}

finProfile1 = startSketchOn(finDiagPlane1)
  |> startProfile(at = [
       tubeInnerDiameter / 2 + tubeThickness,
       stockThickness
     ])
  |> xLine(endAbsolute = sqrt((boltSpacingX / 2) ^ 2 + (boltSpacingY / 2) ^ 2) - counterdrillDiameter)
  |> yLine(length = 0.15)
  |> line(endAbsolute = [
       profileStartX(%) + 0.15,
       stockThickness + tubeHeight * .8
     ])
  |> xLine(length = -0.15)
  |> line(endAbsolute = [profileStartX(%), profileStartY(%)])
  |> close()
finSolid1 = extrude(finProfile1, length = tubeThickness, symmetric = true)

// Pattern to opposite side around Z axis
finPair1 = patternCircular3d(
  finSolid1,
  instances = 2,
  axis = [0, 0, 1],
  center = [0, 0, 0],
  arcDegrees = 360,
  rotateDuplicates = true,
)

// Diagonal plane helper for i = -1
finDiagPlane2 = {
  origin = [0.0, 0.0, 0.0],
  xAxis = [
    boltSpacingX / 2 * -1,
    boltSpacingY / 2,
    0.0
  ],
  yAxis = [0.0, 0.0, 1.0]
}

finProfile2 = startSketchOn(finDiagPlane2)
  |> startProfile(at = [
       tubeInnerDiameter / 2 + tubeThickness,
       stockThickness
     ])
  |> xLine(endAbsolute = sqrt((boltSpacingX / 2) ^ 2 + (boltSpacingY / 2) ^ 2) - counterdrillDiameter)
  |> yLine(length = 0.15)
  |> line(endAbsolute = [
       profileStartX(%) + 0.15,
       stockThickness + tubeHeight * .8
     ])
  |> xLine(length = -0.15)
  |> line(endAbsolute = [profileStartX(%), profileStartY(%)])
  |> close()
finSolid2 = extrude(finProfile2, length = tubeThickness, symmetric = true)

// Pattern to opposite side around Z axis
finPair2 = patternCircular3d(
  finSolid2,
  instances = 2,
  axis = [0, 0, 1],
  center = [0, 0, 0],
  arcDegrees = 360,
  rotateDuplicates = true,
)


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counterdrilled-weldment