ffsshhttiikk What I do
- Create 3D geometric models using CAD software
- Generate CNC toolpaths for manufacturing
- Program CNC machines using G-code and CAM software
- Design for additive manufacturing (3D printing)
- Perform toolpath simulation and verification
- Optimize machining parameters for efficiency
- Convert CAD models to manufacturing formats
- Verify tool collision and machine limits
When to use me
When creating 3D models, generating CNC toolpaths, programming CNC machines, or designing parts for additive manufacturing.
Core Concepts
- Solid modeling (CSG, B-rep)
- Surface modeling and NURBS
- Feature-based modeling
- Toolpath strategies (contour, pocketing, drilling)
- CNC programming (G-code, M-code)
- Feed and speed calculations
- Tool geometry and compensation
- Additive manufacturing processes (FDM, SLA, SLS)
- Build orientation and support generation
- Post-processing for different machine controllers
Code Examples
G-Code Generation
from dataclasses import dataclass
from typing import List, Tuple
import math
@dataclass
class GCodeCommand:
code: str
x: float = None
y: float = None
z: float = None
f: float = None
s: float = None
def rapid_move(x: float, y: float, z: float) -> str:
"""Generate G0 rapid move command."""
return f"G0 X{x:.4f} Y{y:.4f} Z{z:.4f}"
def linear_move(x: float, y: float, z: float, f: float) -> str:
"""Generate G1 linear move command."""
return f"G1 X{x:.4f} Y{y:.4f} Z{z:.4f} F{f:.1f}"
def circular_move(
i: float, j: float, x: float, y: float,
direction: str = "clockwise",
f: float = 100
) -> str:
"""Generate G2/G3 circular move."""
g_code = "G2" if direction == "clockwise" else "G3"
return f"{g_code} X{x:.4f} Y{y:.4f} I{i:.4f} J{j:.4f} F{f:.1f}"
def drill_cycle(
x: float, y: float,
z_start: float,
z_depth: float,
z_retract: float,
f_plunge: float,
f_rapid: float
) -> List[str]:
"""Generate G81 drilling cycle."""
return [
rapid_move(x, y, z_start),
f"G81 R{z_retract} Z{z_depth} F{f_plunge}",
f"G80",
rapid_move(x, y, z_retract)
]
def canned_cycle(
cycle: str,
x: float, y: float,
r: float, z: float,
q: float = None,
f: float = 100
) -> str:
"""Generate canned cycle command."""
if q:
return f"{cycle} R{r} Z{z} Q{q} F{f}"
return f"{cycle} R{r} Z{z} F{f}"
# Example: Simple part program
gcode = [
"G90 G21 G40", # Absolute, mm, cancel compensation
"G54", # Work coordinate system 1
"M6 T1", # Tool change to tool 1
"M3 S3000", # Spindle on clockwise 3000 RPM
rapid_move(0, 0, 5),
linear_move(10, 0, -2, 100),
linear_move(10, 10, -2, 100),
linear_move(0, 10, -2, 100),
linear_move(0, 0, -2, 100),
"M5", # Spindle off
"M30" # Program end
]
for line in gcode[:5]:
print(line)
Toolpath Generation
from typing import List, Tuple
import numpy as np
def offset_polygon(
vertices: List[Tuple[float, float]],
offset: float,
corner_style: str = "round"
) -> List[Tuple[float, float]]:
"""Generate offset contour for tool radius compensation."""
offset_vertices = []
n = len(vertices)
for i in range(n):
p1 = vertices[i]
p2 = vertices[(i + 1) % n]
p0 = vertices[(i - 1) % n]
v1 = np.array(p2) - np.array(p1)
v0 = np.array(p1) - np.array(p0)
angle1 = math.atan2(v1[1], v1[0])
angle0 = math.atan2(v0[1], v0[0])
if corner_style == "round":
radius = offset
center = np.array(p1) + np.array([
radius * math.cos((angle0 + angle1) / 2),
radius * math.sin((angle0 + angle1) / 2)
])
# Generate arc points
for t in np.linspace(0, 1, 9):
angle = angle0 + (angle1 - angle0) * t
offset_vertices.append((
center[0] + radius * math.cos(angle + math.pi/2),
center[1] + radius * math.sin(angle + math.pi/2)
))
else:
# Miter join
bisector = (angle0 + angle1) / 2
offset_vertices.append((
p1[0] + offset * math.cos(bisector + math.pi/2),
p1[1] + offset * math.sin(bisector + math.pi/2)
))
return offset_vertices
def raster_toolpath(
bbox: Tuple[float, float, float, float],
stepover: float,
direction: str = "x"
) -> List[Tuple[float, float]]:
"""Generate raster (zigzag) toolpath."""
xmin, xmax, ymin, ymax = bbox
path = []
if direction == "x":
for y in np.arange(ymin, ymax, stepover):
if (y - ymin) / stepover % 2 == 0:
path.extend([(xmin, y), (xmax, y)])
else:
path.extend([(xmax, y), (xmin, y)])
else:
for x in np.arange(xmin, xmax, stepover):
if (x - xmin) / stepover % 2 == 0:
path.extend([(x, ymin), (x, ymax)])
else:
path.extend([(x, ymax), (x, ymin)])
return path
def spiral_toolpath(
center: Tuple[float, float],
start_radius: float,
end_radius: float,
angle_per_step: float = 0.1,
z_feed: float = 0.01
) -> List[Tuple[float, float, float]]:
"""Generate spiral toolpath for drilling/milling."""
path = []
r = start_radius
theta = 0
while r <= end_radius:
x = center[0] + r * math.cos(theta)
y = center[1] + r * math.sin(theta)
z = -r / end_radius * 5 # Example z-depth
path.append((x, y, z))
r += 0.05
theta += angle_per_step
return path
def trochoidal_milling(
center: Tuple[float, float],
radius: float,
slot_width: float,
stepdown: float,
total_depth: float
) -> List[Tuple[float, float, float]]:
"""Generate trochoidal milling toolpath."""
path = []
current_depth = 0
while current_depth < total_depth:
current_depth += stepdown
if current_depth > total_depth:
current_depth = total_depth
angle = 0
while angle < 2 * math.pi:
x = center[0] + (radius + slot_width/2 * math.cos(angle)) * math.cos(angle/2)
y = center[1] + (radius + slot_width/2 * math.cos(angle)) * math.sin(angle/2)
z = -current_depth
path.append((x, y, z))
angle += 0.2
return path
# Example: Raster toolpath
bbox = (0, 100, 0, 50)
path = raster_toolpath(bbox, 10, "x")
print(f"Generated {len(path)} path points")
Feeds and Speeds
@dataclass
class ToolParameters:
diameter: float # mm
num_flutes: int
material: str
hardness: float # HRC
@dataclass
class MaterialProperties:
name: str
hardness: float # HB or HRC
tensile_strength: float # MPa
machinability_rating: float
def calculate_spindle_speed(
cutting_speed: float,
tool_diameter: float
) -> float:
"""Calculate spindle RPM."""
return (1000 * cutting_speed) / (math.pi * tool_diameter)
def calculate_feed_rate(
spindle_speed: float,
feed_per_tooth: float,
num_flutes: int
) -> float:
"""Calculate feed rate mm/min."""
return spindle_speed * feed_per_tooth * num_flutes
def calculate_material_removal_rate(
width: float,
depth: float,
feed_rate: float
) -> float:
"""Calculate MRR mm³/min."""
return width * depth * feed_rate
def calculate_power_requirement(
mrr: float,
specific_energy: float
) -> float:
"""Calculate cutting power kW."""
return mrr * specific_energy / 60000
def estimate_feeds_speeds(
material: str,
tool_diameter: float,
num_flutes: int,
operation: str
) -> dict:
"""Estimate feeds and speeds based on material and operation."""
material_data = {
"aluminum": {"vc": 200, "fz": 0.08, "se": 600},
"steel": {"vc": 100, "fz": 0.04, "se": 1500},
"stainless": {"vc": 70, "fz": 0.03, "se": 1800},
"titanium": {"vc": 50, "fz": 0.02, "se": 2500}
}
modifiers = {
"roughing": {"vc_mult": 1.2, "fz_mult": 1.2},
"finishing": {"vc_mult": 1.5, "fz_mult": 0.5},
"slotting": {"vc_mult": 0.6, "fz_mult": 0.8}
}
m = material_data.get(material, material_data["steel"])
op_mod = modifiers.get(operation, {"vc_mult": 1.0, "fz_mult": 1.0})
vc = m["vc"] * op_mod["vc_mult"]
fz = m["fz"] * op_mod["fz_mult"]
n = calculate_spindle_speed(vc)
vf, tool_diameter = calculate_feed_rate(n, fz, num_flutes)
return {
"spindle_speed_rpm": n,
"feed_rate_mm_min": vf,
"chip_load_mm_tooth": fz
}
# Example: Feeds and speeds
settings = estimate_feeds_speeds("aluminum", 10, 4, "roughing")
print(f"Spindle speed: {settings['spindle_speed_rpm']:.0f} RPM")
print(f"Feed rate: {settings['feed_rate_mm_min']:.1f} mm/min")
Additive Manufacturing
@dataclass
class AMBuildSettings:
layer_height: float # mm
infill_percentage: float
infill_pattern: str
build_temperature: float # C
bed_temperature: float # C
print_speed: float # mm/s
support_type: str
def estimate_build_time(
num_layers: int,
layer_area: float,
print_speed: float,
travel_speed: float = 150,
layer_change_time: float = 5
) -> float:
"""Estimate total build time in hours."""
print_time = (num_layers * layer_area) / print_speed / 60
travel_factor = 0.3
layer_time = num_layers * layer_change_time / 60
return (print_time * (1 + travel_factor) + layer_time) / 60
def calculate_material_usage(
volume_mm3: float,
infill_percentage: float = 20,
support_percentage: float = 10
) -> float:
"""Calculate required material in grams."""
density = 1.24 # PLA g/cm³
volume_cm3 = volume_mm3 / 1000
total_volume = volume_cm3 * (1 + infill_percentage/100) * (1 + support_percentage/100)
return total_volume * density
def optimize_build_orientation(
surface_area: float,
build_volume: Tuple[float, float, float],
min_surface_roughness: bool = True,
max_strength: bool = False
) -> Tuple[float, float, float]:
"""Optimize part orientation for 3D printing."""
x, y, z = build_volume
if min_surface_roughness:
return (x, y, 0.1) # Largest flat surface down
elif max_strength:
return (0.1, y, z) # Layer lines perpendicular to load
return (x, y, z)
def generate_support_structure(
overhang_angle_threshold: float = 45,
support_density: float = 0.2
) -> List[dict]:
"""Generate support structure parameters."""
return [{
"angle_threshold": overhang_angle_threshold,
"density": support_density,
"style": "tree" if support_density < 0.15 else "grid"
}]
# Example: Build estimation
build = AMBuildSettings(
layer_height=0.2,
infill_percentage=20,
infill_pattern="grid",
print_speed=60
)
time = estimate_build_time(100, 50*50, 60)
material = calculate_material_usage(100*100*100, 20, 10)
print(f"Estimated build time: {time:.1f} hours")
print(f"Material required: {material:.1f} g")
CAM Post-Processing
@dataclass
class PostProcessorConfig:
machine_type: str
control_system: str
output_format: str
arc_output: str
tool_change_mcode: str
coolant_mcodes: Tuple[str, str]
def generate_post_processor(
config: PostProcessorConfig
) -> dict:
"""Generate post-processor configuration."""
return {
"header": [
f"O1234 ({config.machine_type} program)",
"G90 G21 G40",
f"G54 (Work coordinate: {config.control_system})"
],
"tool_change": f"M6 T#{{TOOL_NUMBER}} ({config.tool_change_mcode})",
"coolant_on": config.coolant_mcodes[0],
"coolant_off": config.coolant_mcodes[1],
"arc_format": config.arc_output,
"footer": ["M5", "M30"]
}
def interpolate_gcode(
input_points: List[Tuple[float, float, float]],
tolerance: float = 0.01
) -> List[Tuple[float, float, float]]:
"""Interpolate toolpath with tolerance."""
output = [input_points[0]]
for i in range(1, len(input_points)):
p1 = input_points[i-1]
p2 = input_points[i]
dist = math.sqrt(
(p2[0]-p1[0])**2 +
(p2[1]-p1[1])**2 +
(p2[2]-p1[2])**2
)
num_points = max(2, int(dist / tolerance))
for j in range(1, num_points):
t = j / num_points
output.append((
p1[0] + (p2[0]-p1[0]) * t,
p1[1] + (p2[1]-p1[1]) * t,
p1[2] + (p2[2]-p1[2]) * t
))
return output
def verify_toolpath(
toolpath: List[Tuple[float, float, float]],
machine_limits: dict
) -> List[str]:
"""Verify toolpath against machine limits."""
warnings = []
for i, (x, y, z) in enumerate(toolpath):
if x < machine_limits["x_min"] or x > machine_limits["x_max"]:
warnings.append(f"Point {i}: X={x:.3f} out of range")
if y < machine_limits["y_min"] or y > machine_limits["y_max"]:
warnings.append(f"Point {i}: Y={y:.3f} out of range")
if z < machine_limits["z_min"] or z > machine_limits["z_max"]:
warnings.append(f"Point {i}: Z={z:.3f} out of range")
return warnings
# Example: Post-processor
config = PostProcessorConfig(
machine_type="Haas VF-2",
control_system="Fanuc",
output_format="XYZ",
arc_output="IJ",
tool_change_mcode="M6",
coolant_on="M8",
coolant_off="M9"
)
post = generate_post_processor(config)
print("Header:", post["header"][1])
print("Footer:", post["footer"][1])
Best Practices
- Always verify toolpaths before cutting using simulation
- Use proper work coordinate systems and origin points
- Consider tool deflection and vibration in feed/speed calculations
- Use appropriate stock allowances for finish passes
- Verify machine limits and tool lengths before running programs
- Optimize toolpaths for reduced cycle time
- Use proper fixturing to minimize vibration
- Consider tolerances and shrink factors in CAD models
- Document CAM settings and post-processor configuration
- Test programs with air cuts before production runs