SME
Manufacturing Processes · Problem type
The stair-step error on a sloped face
Use this for “0.2 mm layers on a face at 30° from the build plate. How high is the cusp?”
Diagram
c = t cos θ = 0.2 mm × cos 30° = 0.173 mm: how far each step stands off the face.
Steps enlarged; θ is measured from the build plate.
This is an example. Type your own values to start a new problem.
c (mm)
=
t (mm)
×
cos(
θ
°)
Formulas
c
=
t
×
cos(
θ
°)
0.1732 = 0.2 × cos(30°)
Assumptions
•
Each layer’s edge meets the true face at its lower corner; the upper corner stands off it.
•
θ is the face’s angle from the build plate: 90° is a vertical wall, with no cusp.
•
The cusp c is measured square to the true face.
Step-by-step
WE KNOW
t = 0.2 mm, θ = 30°
FIND
cusp height (c)
Step 1 · Find cusp height (c)
Use c = t × cos(θ°)
Each
step’s
riser
t
stands
at
θ
to
the
face’s
normal,
so
its
corner
sits
t
cos
θ
off
the
face.
c
=
0.2
×
cos(30°)
c
=
0.2
×
0.866
c
=
0.1732
mm
Check
Put the numbers back in. Both sides should match.
0.1732 = 0.2 × cos(30°) ✓
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.
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