steve/inch-flat-washer

Plain washer, inch: ASME B18.21.1 / B18.22.1 Type A (SAE narrow N / USS wide W) and fender washers, #0 to 1/2 in.

v1.1.0 Latest STEVE MIT 0

Open in STEVE

Isometric

Parameters

Preset20 sizes

Size26 options

Screw size and series: N narrow (SAE), W wide (USS), F fender.

Material3 options

steel: carbon steel, zinc plated; stainless-18-8 (304) or stainless-316.

Defaults built

part.py 70 lines · Python · STEVE runtime · checked

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"""Plain washer, inch series, Type A preferred sizes of ASME B18.21.1-2009 (formerly B18.22.1-1965; narrow N and wide W

series), for #0 to 1/2 in screws; and fender washers (F) for #0 to 1/2 in screws as step.parts' published models draw

them (no standard covers fender washers).

Envelope model: a flat ring (inside diameter ID, outside diameter OD, thickness T, nominal values). It sits on the

XY plane, centred on the origin, axis along +Z. The model is in millimetres (1 in = 25.4 mm).

"""

from steve import Model

size = "1/4 N" # Washer size (screw size, series)

material = "steel" # Material

# Inches. Type A plain washers, preferred sizes: size: (inside diameter ID, outside diameter OD, thickness T), basic

# values. ASME B18.21.1-2009 (R2016), which took over B18.22.1-1965 unchanged, as reproduced at

# https://amesweb.info/Fasteners/Washers/Type-A-Plain-Washers-Dimensions-Chart.aspx (sizes No. 0, 2, 4 named there);

# same values in B18.22.1-1965 (R1998) at https://engineersedge.com/plain_washers.htm and

# https://www.globalfastener.com/standards/detail_1111.html (Table 1A).

WASHERS = {

"#0": (0.078, 0.188, 0.020),

"#2": (0.094, 0.250, 0.020),

"#4": (0.125, 0.312, 0.032),

"#6": (0.156, 0.375, 0.049),

"#8": (0.188, 0.438, 0.049),

"#10": (0.219, 0.500, 0.049),

"1/4 N": (0.281, 0.625, 0.065),

"1/4 W": (0.312, 0.734, 0.065),

"5/16 N": (0.344, 0.688, 0.065),

"5/16 W": (0.375, 0.875, 0.083),

"3/8 N": (0.406, 0.812, 0.065),

"3/8 W": (0.438, 1.000, 0.083),

"7/16 N": (0.469, 0.922, 0.065),

"7/16 W": (0.500, 1.250, 0.083),

"1/2 N": (0.531, 1.062, 0.095),

"1/2 W": (0.562, 1.375, 0.109),

}

# Fender washers (F), mm: measured on step.parts' models asme_fender_washer_<size>_simple (MIT; their bore and outside

# cylinder radii and their thickness, read from the faces). No standard covers fender washers; these models are

# proportional (OD 3.2 d, ID 1.08 d, T 0.18 d with d the screw's nominal diameter, T at least 0.45 mm).

# size: (inside diameter ID, outside diameter OD, thickness T)

FENDER = {

"#0 F": (1.646, 4.8768, 0.45),

"#2 F": (2.3592, 6.9901, 0.45),

"#4 F": (3.0724, 9.1034, 0.5121),

"#6 F": (3.7856, 11.2166, 0.6309),

"#8 F": (4.4988, 13.3299, 0.7498),

"#10 F": (5.212, 15.4432, 0.8687),

"1/4 F": (6.858, 20.32, 1.143),

"5/16 F": (8.5724, 25.4, 1.4287),

"3/8 F": (10.287, 30.48, 1.7145),

"1/2 F": (13.716, 40.64, 2.286),

}

# material choice: (STEVE material library id, appearance colour)

MATERIALS = {

"steel": ("steel-generic", "#b8bcc2"), # carbon steel, zinc plated

"stainless-18-8": ("stainless-304", "#c9ccd0"),

"stainless-316": ("stainless-316", "#c9ccd0"),

}

INCH = 25.4

ID, OD, T = FENDER[size] if size in FENDER else (v * INCH for v in WASHERS[size])

material_id, colour = MATERIALS[material]

model = Model()

with model.sketch("washer_sketch", on="XY", name="Washer") as sk:

sk.circle("outside", (0, 0), OD / 2)

sk.circle("inside", (0, 0), ID / 2)

model.extrude("washer", "washer_sketch", distance=T, name="Washer")

model.material(material_id, color=colour)

result = model.result()

"""Plain washer, inch series, Type A preferred sizes of ASME B18.21.1-2009 (formerly B18.22.1-1965; narrow N and wide W
series), for #0 to 1/2 in screws; and fender washers (F) for #0 to 1/2 in screws as step.parts' published models draw
them (no standard covers fender washers).

Envelope model: a flat ring (inside diameter ID, outside diameter OD, thickness T, nominal values). It sits on the
XY plane, centred on the origin, axis along +Z. The model is in millimetres (1 in = 25.4 mm).
"""
from steve import Model

size = "1/4 N"  # Washer size (screw size, series)
material = "steel"  # Material

# Inches. Type A plain washers, preferred sizes: size: (inside diameter ID, outside diameter OD, thickness T), basic
# values. ASME B18.21.1-2009 (R2016), which took over B18.22.1-1965 unchanged, as reproduced at
# https://amesweb.info/Fasteners/Washers/Type-A-Plain-Washers-Dimensions-Chart.aspx (sizes No. 0, 2, 4 named there);
# same values in B18.22.1-1965 (R1998) at https://engineersedge.com/plain_washers.htm and
# https://www.globalfastener.com/standards/detail_1111.html (Table 1A).
WASHERS = {
    "#0": (0.078, 0.188, 0.020),
    "#2": (0.094, 0.250, 0.020),
    "#4": (0.125, 0.312, 0.032),
    "#6": (0.156, 0.375, 0.049),
    "#8": (0.188, 0.438, 0.049),
    "#10": (0.219, 0.500, 0.049),
    "1/4 N": (0.281, 0.625, 0.065),
    "1/4 W": (0.312, 0.734, 0.065),
    "5/16 N": (0.344, 0.688, 0.065),
    "5/16 W": (0.375, 0.875, 0.083),
    "3/8 N": (0.406, 0.812, 0.065),
    "3/8 W": (0.438, 1.000, 0.083),
    "7/16 N": (0.469, 0.922, 0.065),
    "7/16 W": (0.500, 1.250, 0.083),
    "1/2 N": (0.531, 1.062, 0.095),
    "1/2 W": (0.562, 1.375, 0.109),
}
# Fender washers (F), mm: measured on step.parts' models asme_fender_washer_<size>_simple (MIT; their bore and outside
# cylinder radii and their thickness, read from the faces). No standard covers fender washers; these models are
# proportional (OD 3.2 d, ID 1.08 d, T 0.18 d with d the screw's nominal diameter, T at least 0.45 mm).
# size: (inside diameter ID, outside diameter OD, thickness T)
FENDER = {
    "#0 F": (1.646, 4.8768, 0.45),
    "#2 F": (2.3592, 6.9901, 0.45),
    "#4 F": (3.0724, 9.1034, 0.5121),
    "#6 F": (3.7856, 11.2166, 0.6309),
    "#8 F": (4.4988, 13.3299, 0.7498),
    "#10 F": (5.212, 15.4432, 0.8687),
    "1/4 F": (6.858, 20.32, 1.143),
    "5/16 F": (8.5724, 25.4, 1.4287),
    "3/8 F": (10.287, 30.48, 1.7145),
    "1/2 F": (13.716, 40.64, 2.286),
}
# material choice: (STEVE material library id, appearance colour)
MATERIALS = {
    "steel": ("steel-generic", "#b8bcc2"),        # carbon steel, zinc plated
    "stainless-18-8": ("stainless-304", "#c9ccd0"),
    "stainless-316": ("stainless-316", "#c9ccd0"),
}
INCH = 25.4

ID, OD, T = FENDER[size] if size in FENDER else (v * INCH for v in WASHERS[size])
material_id, colour = MATERIALS[material]

model = Model()
with model.sketch("washer_sketch", on="XY", name="Washer") as sk:
    sk.circle("outside", (0, 0), OD / 2)
    sk.circle("inside", (0, 0), ID / 2)
model.extrude("washer", "washer_sketch", distance=T, name="Washer")
model.material(material_id, color=colour)
result = model.result()

pypart.toml 169 lines · TOML

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name = "steve/inch-flat-washer"

version = "1.1.0"

runtime = "steve"

license = "MIT"

summary = "Plain washer, inch: ASME B18.21.1 / B18.22.1 Type A (SAE narrow N / USS wide W) and fender washers, #0 to 1/2 in."

description = """Type A plain washer of ASME B18.21.1-2009 (formerly B18.22.1-1965, same table), narrow (N, the "SAE" series) and \

wide (W, the "USS" series), for #0 to 1/2 in screws. A flat ring at the table's nominal inside diameter, outside diameter and thickness. \

Also fender washers (F, large outside diameter) for #0 to 1/2 in screws, measured from step.parts' published models (MIT): \

no standard covers fender washers.

It sits on the XY plane, centred on the origin (the model is in millimetres). Dimensions from the Type A preferred sizes table \

(see the README)."""

changes = "Fender washers (F) for #0 to 1/2 in screws added, measured from step.parts' published models (MIT); Type A sizes unchanged."

tags = ["fastener", "washer", "flat-washer", "plain-washer", "fender-washer", "sae", "uss", "asme-b18-22-1", "asme-b18-21-1", "inch"]

[parameters.size]

type = "choice"

default = "1/4 N"

choices = ["#0", "#2", "#4", "#6", "#8", "#10", "1/4 N", "1/4 W", "5/16 N", "5/16 W", "3/8 N", "3/8 W", "7/16 N", "7/16 W", "1/2 N", "1/2 W", "#0 F", "#2 F", "#4 F", "#6 F", "#8 F", "#10 F", "1/4 F", "5/16 F", "3/8 F", "1/2 F"]

label = "Size"

description = "Screw size and series: N narrow (SAE), W wide (USS), F fender."

[parameters.material]

type = "choice"

default = "steel"

choices = ["steel", "stainless-18-8", "stainless-316"]

label = "Material"

description = "steel: carbon steel, zinc plated; stainless-18-8 (304) or stainless-316."

[[presets]]

id = "no0"

title = "#0 plain washer"

params = { size = "#0" }

aliases = ["#0 SAE washer", "#0 flat washer", "#0 plain washer Type A", "ASME B18.21.1 #0 washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "no2"

title = "#2 plain washer"

params = { size = "#2" }

aliases = ["#2 SAE washer", "#2 flat washer", "#2 plain washer Type A", "ASME B18.21.1 #2 washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "no4"

title = "#4 plain washer"

params = { size = "#4" }

aliases = ["#4 SAE washer", "#4 flat washer", "#4 plain washer Type A", "ASME B18.21.1 #4 washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "no6"

title = "#6 plain washer"

params = { size = "#6" }

aliases = ["#6 SAE washer", "#6 flat washer", "#6 plain washer Type A", "ASME B18.21.1 #6 washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "no8"

title = "#8 plain washer"

params = { size = "#8" }

aliases = ["#8 SAE washer", "#8 flat washer", "#8 plain washer Type A", "ASME B18.21.1 #8 washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "no10"

title = "#10 plain washer"

params = { size = "#10" }

aliases = ["#10 SAE washer", "#10 flat washer", "#10 plain washer Type A", "ASME B18.21.1 #10 washer", "#10 plain washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "1-4-N"

title = "1/4 N narrow (SAE) plain washer"

params = { size = "1/4 N" }

aliases = ["1/4 SAE washer", "1/4 flat washer", "1/4 plain washer Type A", "ASME B18.21.1 1/4 washer", "1/4 N narrow (SAE) plain washer", "ANSI-ASME B18.22.1 SAE Std Plain Washer 1 4"]

standard = "ASME B18.22.1"

[[presets]]

id = "5-16-N"

title = "5/16 N narrow (SAE) plain washer"

params = { size = "5/16 N" }

aliases = ["5/16 SAE washer", "5/16 flat washer", "5/16 plain washer Type A", "ASME B18.21.1 5/16 washer", "5/16 N narrow (SAE) plain washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "3-8-N"

title = "3/8 N narrow (SAE) plain washer"

params = { size = "3/8 N" }

aliases = ["3/8 SAE washer", "3/8 flat washer", "3/8 plain washer Type A", "ASME B18.21.1 3/8 washer", "3/8 N narrow (SAE) plain washer"]

standard = "ASME B18.22.1"

[[presets]]

id = "1-2-N"

title = "1/2 N narrow (SAE) plain washer"

params = { size = "1/2 N" }

aliases = ["1/2 SAE washer", "1/2 flat washer", "1/2 plain washer Type A", "ASME B18.21.1 1/2 washer", "1/2 N narrow (SAE) plain washer"]

standard = "ASME B18.22.1"

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[[presets]]

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id = "no0-fender"

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title = "#0 fender washer"

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params = { size = "#0 F" }

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aliases = ["#0 fender washer", "#0 large OD washer", "#0 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "no2-fender"

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title = "#2 fender washer"

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params = { size = "#2 F" }

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aliases = ["#2 fender washer", "#2 large OD washer", "#2 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "no4-fender"

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title = "#4 fender washer"

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params = { size = "#4 F" }

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aliases = ["#4 fender washer", "#4 large OD washer", "#4 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "no6-fender"

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title = "#6 fender washer"

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params = { size = "#6 F" }

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aliases = ["#6 fender washer", "#6 large OD washer", "#6 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "no8-fender"

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title = "#8 fender washer"

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params = { size = "#8 F" }

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aliases = ["#8 fender washer", "#8 large OD washer", "#8 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "no10-fender"

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title = "#10 fender washer"

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params = { size = "#10 F" }

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aliases = ["#10 fender washer", "#10 large OD washer", "#10 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "1-4-fender"

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title = "1/4 fender washer"

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params = { size = "1/4 F" }

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aliases = ["1/4 fender washer", "1/4 large OD washer", "1/4 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "5-16-fender"

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title = "5/16 fender washer"

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params = { size = "5/16 F" }

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aliases = ["5/16 fender washer", "5/16 large OD washer", "5/16 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "3-8-fender"

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title = "3/8 fender washer"

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params = { size = "3/8 F" }

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aliases = ["3/8 fender washer", "3/8 large OD washer", "3/8 penny washer"]

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standard = "step.parts fender washer model"

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[[presets]]

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id = "1-2-fender"

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title = "1/2 fender washer"

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params = { size = "1/2 F" }

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aliases = ["1/2 fender washer", "1/2 large OD washer", "1/2 penny washer"]

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standard = "step.parts fender washer model"

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name = "steve/inch-flat-washer"
version = "1.1.0"
runtime = "steve"
license = "MIT"
summary = "Plain washer, inch: ASME B18.21.1 / B18.22.1 Type A (SAE narrow N / USS wide W) and fender washers, #0 to 1/2 in."
description = """Type A plain washer of ASME B18.21.1-2009 (formerly B18.22.1-1965, same table), narrow (N, the "SAE" series) and \
wide (W, the "USS" series), for #0 to 1/2 in screws. A flat ring at the table's nominal inside diameter, outside diameter and thickness. \
Also fender washers (F, large outside diameter) for #0 to 1/2 in screws, measured from step.parts' published models (MIT): \
no standard covers fender washers.

It sits on the XY plane, centred on the origin (the model is in millimetres). Dimensions from the Type A preferred sizes table \
(see the README)."""
changes = "Fender washers (F) for #0 to 1/2 in screws added, measured from step.parts' published models (MIT); Type A sizes unchanged."
tags = ["fastener", "washer", "flat-washer", "plain-washer", "fender-washer", "sae", "uss", "asme-b18-22-1", "asme-b18-21-1", "inch"]

[parameters.size]
type = "choice"
default = "1/4 N"
choices = ["#0", "#2", "#4", "#6", "#8", "#10", "1/4 N", "1/4 W", "5/16 N", "5/16 W", "3/8 N", "3/8 W", "7/16 N", "7/16 W", "1/2 N", "1/2 W", "#0 F", "#2 F", "#4 F", "#6 F", "#8 F", "#10 F", "1/4 F", "5/16 F", "3/8 F", "1/2 F"]
label = "Size"
description = "Screw size and series: N narrow (SAE), W wide (USS), F fender."

[parameters.material]
type = "choice"
default = "steel"
choices = ["steel", "stainless-18-8", "stainless-316"]
label = "Material"
description = "steel: carbon steel, zinc plated; stainless-18-8 (304) or stainless-316."

[[presets]]
id = "no0"
title = "#0 plain washer"
params = { size = "#0" }
aliases = ["#0 SAE washer", "#0 flat washer", "#0 plain washer Type A", "ASME B18.21.1 #0 washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "no2"
title = "#2 plain washer"
params = { size = "#2" }
aliases = ["#2 SAE washer", "#2 flat washer", "#2 plain washer Type A", "ASME B18.21.1 #2 washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "no4"
title = "#4 plain washer"
params = { size = "#4" }
aliases = ["#4 SAE washer", "#4 flat washer", "#4 plain washer Type A", "ASME B18.21.1 #4 washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "no6"
title = "#6 plain washer"
params = { size = "#6" }
aliases = ["#6 SAE washer", "#6 flat washer", "#6 plain washer Type A", "ASME B18.21.1 #6 washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "no8"
title = "#8 plain washer"
params = { size = "#8" }
aliases = ["#8 SAE washer", "#8 flat washer", "#8 plain washer Type A", "ASME B18.21.1 #8 washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "no10"
title = "#10 plain washer"
params = { size = "#10" }
aliases = ["#10 SAE washer", "#10 flat washer", "#10 plain washer Type A", "ASME B18.21.1 #10 washer", "#10 plain washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "1-4-N"
title = "1/4 N narrow (SAE) plain washer"
params = { size = "1/4 N" }
aliases = ["1/4 SAE washer", "1/4 flat washer", "1/4 plain washer Type A", "ASME B18.21.1 1/4 washer", "1/4 N narrow (SAE) plain washer", "ANSI-ASME B18.22.1 SAE Std Plain Washer 1 4"]
standard = "ASME B18.22.1"

[[presets]]
id = "5-16-N"
title = "5/16 N narrow (SAE) plain washer"
params = { size = "5/16 N" }
aliases = ["5/16 SAE washer", "5/16 flat washer", "5/16 plain washer Type A", "ASME B18.21.1 5/16 washer", "5/16 N narrow (SAE) plain washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "3-8-N"
title = "3/8 N narrow (SAE) plain washer"
params = { size = "3/8 N" }
aliases = ["3/8 SAE washer", "3/8 flat washer", "3/8 plain washer Type A", "ASME B18.21.1 3/8 washer", "3/8 N narrow (SAE) plain washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "1-2-N"
title = "1/2 N narrow (SAE) plain washer"
params = { size = "1/2 N" }
aliases = ["1/2 SAE washer", "1/2 flat washer", "1/2 plain washer Type A", "ASME B18.21.1 1/2 washer", "1/2 N narrow (SAE) plain washer"]
standard = "ASME B18.22.1"

[[presets]]
id = "no0-fender"
title = "#0 fender washer"
params = { size = "#0 F" }
aliases = ["#0 fender washer", "#0 large OD washer", "#0 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "no2-fender"
title = "#2 fender washer"
params = { size = "#2 F" }
aliases = ["#2 fender washer", "#2 large OD washer", "#2 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "no4-fender"
title = "#4 fender washer"
params = { size = "#4 F" }
aliases = ["#4 fender washer", "#4 large OD washer", "#4 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "no6-fender"
title = "#6 fender washer"
params = { size = "#6 F" }
aliases = ["#6 fender washer", "#6 large OD washer", "#6 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "no8-fender"
title = "#8 fender washer"
params = { size = "#8 F" }
aliases = ["#8 fender washer", "#8 large OD washer", "#8 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "no10-fender"
title = "#10 fender washer"
params = { size = "#10 F" }
aliases = ["#10 fender washer", "#10 large OD washer", "#10 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "1-4-fender"
title = "1/4 fender washer"
params = { size = "1/4 F" }
aliases = ["1/4 fender washer", "1/4 large OD washer", "1/4 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "5-16-fender"
title = "5/16 fender washer"
params = { size = "5/16 F" }
aliases = ["5/16 fender washer", "5/16 large OD washer", "5/16 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "3-8-fender"
title = "3/8 fender washer"
params = { size = "3/8 F" }
aliases = ["3/8 fender washer", "3/8 large OD washer", "3/8 penny washer"]
standard = "step.parts fender washer model"

[[presets]]
id = "1-2-fender"
title = "1/2 fender washer"
params = { size = "1/2 F" }
aliases = ["1/2 fender washer", "1/2 large OD washer", "1/2 penny washer"]
standard = "step.parts fender washer model"

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Plain washer, inch (ASME B18.21.1 / B18.22.1 Type A)

Type A plain washer for inch screws, narrow series N (the "SAE" washer) and wide series W (the "USS" washer), #0 to 1/2 in; and fender washers (F) for #0 to 1/2 in screws. Presets cover the catalogue's flat washers (the narrow washer for each screw size) and its fender washers.

Geometry

A flat ring at the table's nominal inside diameter ID, outside diameter OD and thickness T. It sits on the XY plane, centred on the origin.

Parameters

Parameter	Meaning
`size`	Screw size and series: `1/4 N` (narrow, SAE), `1/4 W` (wide, USS), ...; `#0` to `#10` have one series; `#0 F` to `1/2 F` fender washers
`material`	`steel` (carbon steel, zinc plated), `stainless-18-8` (304), `stainless-316`

Source

Type A plain washers, preferred sizes: inside diameter, outside diameter and thickness, basic values.

ASME B18.21.1-2009 (R2016), Washers: Helical Spring-Lock, Tooth Lock, and Plain Washers (Inch Series), Type A plain washers, preferred sizes, as reproduced at https://amesweb.info/Fasteners/Washers/Type-A-Plain-Washers-Dimensions-Chart.aspx. This edition names the three smallest rows No. 0, No. 2 and No. 4.
The same values in ANSI/ASME B18.22.1-1965 (R1998), Plain Washers, Table 1A: https://engineersedge.com/plain_washers.htm, https://www.globalfastener.com/standards/detail_1111.html (that edition leaves the size column of the 0.078, 0.094 and 0.125 in rows blank).
B18.22.1 was consolidated into B18.21.1 (ASME: https://www.asme.org/codes-standards/find-codes-standards/b18-21-1-washers-helical-spring-lock-tooth-lock-plain-washers). The presets name ASME B18.22.1, the designation the catalogue uses; the values are those of both editions.

Inch values as in the table; the model converts them to millimetres (1 in = 25.4 mm).

Size	ID	OD	T
#0	0.078	0.188	0.020
#2	0.094	0.250	0.020
#4	0.125	0.312	0.032
#6	0.156	0.375	0.049
#8	0.188	0.438	0.049
#10	0.219	0.500	0.049
1/4 N	0.281	0.625	0.065
1/4 W	0.312	0.734	0.065
5/16 N	0.344	0.688	0.065
5/16 W	0.375	0.875	0.083
3/8 N	0.406	0.812	0.065
3/8 W	0.438	1.000	0.083
7/16 N	0.469	0.922	0.065
7/16 W	0.500	1.250	0.083
1/2 N	0.531	1.062	0.095
1/2 W	0.562	1.375	0.109

Changed in this audit: the sizes "#2 (3/32)" and "#4 (1/8)" are now "#2" and "#4" (the B18.21.1-2009 names; "3/32" and "1/8" were in no source), and the No. 0 row (#0 screws) was added from the same table.

Sources: fender washers

No standard covers fender washers, and suppliers sell several outside diameters and thicknesses for each screw size. The fender sizes' geometry was measured from the published reference models below (each model's bore and outside cylinder radii and its thickness, read from its faces) and is checked preset by preset against them (bounding box within 0.05 mm, volume within 2 %).

step.parts, asme_fender_washer_<size>_simple for #0-80 to 1/2-13 (https://www.step.parts, repository https://github.com/earthtojake/step.parts, commit c6113328, catalog/step/): step.parts' own "analytic simplified" models, original project material under the repository's MIT licence (© 2026 earthtojake).

The models are proportional to the screw's nominal diameter d: OD 3.2 d, ID 1.08 d, T 0.18 d (at least 0.45 mm). Note that ID 1.08 d is a close clearance; check a supplier's washer where the fit matters. The catalogue's 5/16-24, 3/8-24 and 1/2-20 fender models are drawn for a 1/8 in screw (OD 0.4 in, bore smaller than the named screw) and are not presets.

Size, mm:

Size	ID	OD	T
#0 F	1.646	4.8768	0.45
#2 F	2.3592	6.9901	0.45
#4 F	3.0724	9.1034	0.5121
#6 F	3.7856	11.2166	0.6309
#8 F	4.4988	13.3299	0.7498
#10 F	5.212	15.4432	0.8687
1/4 F	6.858	20.32	1.143
5/16 F	8.5724	25.4	1.4287
3/8 F	10.287	30.48	1.7145
1/2 F	13.716	40.64	2.286

Preset list: sizes of the step.parts catalogue (MIT), see library/NOTICE.md.

# Plain washer, inch (ASME B18.21.1 / B18.22.1 Type A)

Type A plain washer for inch screws, narrow series N (the "SAE" washer) and wide series W (the "USS" washer), #0 to

1/2 in; and fender washers (F) for #0 to 1/2 in screws. Presets cover the catalogue's flat washers (the narrow washer

for each screw size) and its fender washers.

## Geometry

A flat ring at the table's nominal inside diameter **ID**, outside diameter **OD** and thickness **T**. It sits on

the XY plane, centred on the origin.

## Parameters

| Parameter | Meaning |

|---|---|

| `size` | Screw size and series: `1/4 N` (narrow, SAE), `1/4 W` (wide, USS), ...; `#0` to `#10` have one series; `#0 F` to `1/2 F` fender washers |

| `material` | `steel` (carbon steel, zinc plated), `stainless-18-8` (304), `stainless-316` |

## Source

Type A plain washers, preferred sizes: inside diameter, outside diameter and thickness, basic values.

- ASME B18.21.1-2009 (R2016), *Washers: Helical Spring-Lock, Tooth Lock, and Plain Washers (Inch Series)*, Type A

plain washers, preferred sizes, as reproduced at

<https://amesweb.info/Fasteners/Washers/Type-A-Plain-Washers-Dimensions-Chart.aspx>. This edition names the three

smallest rows No. 0, No. 2 and No. 4.

- The same values in ANSI/ASME B18.22.1-1965 (R1998), *Plain Washers*, Table 1A:

<https://engineersedge.com/plain_washers.htm>, <https://www.globalfastener.com/standards/detail_1111.html> (that

edition leaves the size column of the 0.078, 0.094 and 0.125 in rows blank).

- B18.22.1 was consolidated into B18.21.1 (ASME:

<https://www.asme.org/codes-standards/find-codes-standards/b18-21-1-washers-helical-spring-lock-tooth-lock-plain-washers>).

The presets name ASME B18.22.1, the designation the catalogue uses; the values are those of both editions.

Inch values as in the table; the model converts them to millimetres (1 in = 25.4 mm).

| Size | ID | OD | T |

|---|---|---|---|

| #0 | 0.078 | 0.188 | 0.020 |

| #2 | 0.094 | 0.250 | 0.020 |

| #4 | 0.125 | 0.312 | 0.032 |

| #6 | 0.156 | 0.375 | 0.049 |

| #8 | 0.188 | 0.438 | 0.049 |

| #10 | 0.219 | 0.500 | 0.049 |

| 1/4 N | 0.281 | 0.625 | 0.065 |

| 1/4 W | 0.312 | 0.734 | 0.065 |

| 5/16 N | 0.344 | 0.688 | 0.065 |

| 5/16 W | 0.375 | 0.875 | 0.083 |

| 3/8 N | 0.406 | 0.812 | 0.065 |

| 3/8 W | 0.438 | 1.000 | 0.083 |

| 7/16 N | 0.469 | 0.922 | 0.065 |

| 7/16 W | 0.500 | 1.250 | 0.083 |

| 1/2 N | 0.531 | 1.062 | 0.095 |

| 1/2 W | 0.562 | 1.375 | 0.109 |

Changed in this audit: the sizes "#2 (3/32)" and "#4 (1/8)" are now "#2" and "#4" (the B18.21.1-2009 names; "3/32"

and "1/8" were in no source), and the No. 0 row (#0 screws) was added from the same table.

## Sources: fender washers

No standard covers fender washers, and suppliers sell several outside diameters and thicknesses for each screw size.

**The fender sizes' geometry was measured from the published reference models** below (each model's bore and outside

cylinder radii and its thickness, read from its faces) and is checked preset by preset against them (bounding box

within 0.05 mm, volume within 2 %).

- **step.parts**, `asme_fender_washer_<size>_simple` for #0-80 to 1/2-13 (https://www.step.parts, repository

https://github.com/earthtojake/step.parts, commit c6113328, `catalog/step/`): step.parts' own "analytic simplified"

The models are proportional to the screw's nominal diameter d: OD 3.2 d, ID 1.08 d, T 0.18 d (at least 0.45 mm).

Note that ID 1.08 d is a close clearance; check a supplier's washer where the fit matters. The catalogue's 5/16-24,

3/8-24 and 1/2-20 fender models are drawn for a 1/8 in screw (OD 0.4 in, bore smaller than the named screw) and are

not presets.

Size, mm:

| Size | ID | OD | T |

|---|---|---|---|

| #0 F | 1.646 | 4.8768 | 0.45 |

| #2 F | 2.3592 | 6.9901 | 0.45 |

| #4 F | 3.0724 | 9.1034 | 0.5121 |

| #6 F | 3.7856 | 11.2166 | 0.6309 |

| #8 F | 4.4988 | 13.3299 | 0.7498 |

| #10 F | 5.212 | 15.4432 | 0.8687 |

| 1/4 F | 6.858 | 20.32 | 1.143 |

| 5/16 F | 8.5724 | 25.4 | 1.4287 |

| 3/8 F | 10.287 | 30.48 | 1.7145 |

| 1/2 F | 13.716 | 40.64 | 2.286 |

Preset list: sizes of the step.parts catalogue (MIT), see `library/NOTICE.md`.

# Plain washer, inch (ASME B18.21.1 / B18.22.1 Type A)

Type A plain washer for inch screws, narrow series N (the "SAE" washer) and wide series W (the "USS" washer), #0 to
1/2 in; and fender washers (F) for #0 to 1/2 in screws. Presets cover the catalogue's flat washers (the narrow washer
for each screw size) and its fender washers.

## Geometry

A flat ring at the table's nominal inside diameter **ID**, outside diameter **OD** and thickness **T**. It sits on
the XY plane, centred on the origin.

## Parameters

| Parameter | Meaning |
|---|---|
| `size` | Screw size and series: `1/4 N` (narrow, SAE), `1/4 W` (wide, USS), ...; `#0` to `#10` have one series; `#0 F` to `1/2 F` fender washers |
| `material` | `steel` (carbon steel, zinc plated), `stainless-18-8` (304), `stainless-316` |

## Source

Type A plain washers, preferred sizes: inside diameter, outside diameter and thickness, basic values.

- ASME B18.21.1-2009 (R2016), *Washers: Helical Spring-Lock, Tooth Lock, and Plain Washers (Inch Series)*, Type A
  plain washers, preferred sizes, as reproduced at
  <https://amesweb.info/Fasteners/Washers/Type-A-Plain-Washers-Dimensions-Chart.aspx>. This edition names the three
  smallest rows No. 0, No. 2 and No. 4.
- The same values in ANSI/ASME B18.22.1-1965 (R1998), *Plain Washers*, Table 1A:
  <https://engineersedge.com/plain_washers.htm>, <https://www.globalfastener.com/standards/detail_1111.html> (that
  edition leaves the size column of the 0.078, 0.094 and 0.125 in rows blank).
- B18.22.1 was consolidated into B18.21.1 (ASME:
  <https://www.asme.org/codes-standards/find-codes-standards/b18-21-1-washers-helical-spring-lock-tooth-lock-plain-washers>).
  The presets name ASME B18.22.1, the designation the catalogue uses; the values are those of both editions.

Inch values as in the table; the model converts them to millimetres (1 in = 25.4 mm).

| Size | ID | OD | T |
|---|---|---|---|
| #0 | 0.078 | 0.188 | 0.020 |
| #2 | 0.094 | 0.250 | 0.020 |
| #4 | 0.125 | 0.312 | 0.032 |
| #6 | 0.156 | 0.375 | 0.049 |
| #8 | 0.188 | 0.438 | 0.049 |
| #10 | 0.219 | 0.500 | 0.049 |
| 1/4 N | 0.281 | 0.625 | 0.065 |
| 1/4 W | 0.312 | 0.734 | 0.065 |
| 5/16 N | 0.344 | 0.688 | 0.065 |
| 5/16 W | 0.375 | 0.875 | 0.083 |
| 3/8 N | 0.406 | 0.812 | 0.065 |
| 3/8 W | 0.438 | 1.000 | 0.083 |
| 7/16 N | 0.469 | 0.922 | 0.065 |
| 7/16 W | 0.500 | 1.250 | 0.083 |
| 1/2 N | 0.531 | 1.062 | 0.095 |
| 1/2 W | 0.562 | 1.375 | 0.109 |

Changed in this audit: the sizes "#2 (3/32)" and "#4 (1/8)" are now "#2" and "#4" (the B18.21.1-2009 names; "3/32"
and "1/8" were in no source), and the No. 0 row (#0 screws) was added from the same table.

## Sources: fender washers

No standard covers fender washers, and suppliers sell several outside diameters and thicknesses for each screw size.
**The fender sizes' geometry was measured from the published reference models** below (each model's bore and outside
cylinder radii and its thickness, read from its faces) and is checked preset by preset against them (bounding box
within 0.05 mm, volume within 2 %).

- **step.parts**, `asme_fender_washer_<size>_simple` for #0-80 to 1/2-13 (https://www.step.parts, repository
  https://github.com/earthtojake/step.parts, commit c6113328, `catalog/step/`): step.parts' own "analytic simplified"
  models, original project material under the repository's **MIT** licence (© 2026 earthtojake).

The models are proportional to the screw's nominal diameter d: OD 3.2 d, ID 1.08 d, T 0.18 d (at least 0.45 mm).
Note that ID 1.08 d is a close clearance; check a supplier's washer where the fit matters. The catalogue's 5/16-24,
3/8-24 and 1/2-20 fender models are drawn for a 1/8 in screw (OD 0.4 in, bore smaller than the named screw) and are
not presets.

Size, mm:

| Size | ID | OD | T |
|---|---|---|---|
| #0 F | 1.646 | 4.8768 | 0.45 |
| #2 F | 2.3592 | 6.9901 | 0.45 |
| #4 F | 3.0724 | 9.1034 | 0.5121 |
| #6 F | 3.7856 | 11.2166 | 0.6309 |
| #8 F | 4.4988 | 13.3299 | 0.7498 |
| #10 F | 5.212 | 15.4432 | 0.8687 |
| 1/4 F | 6.858 | 20.32 | 1.143 |
| 5/16 F | 8.5724 | 25.4 | 1.4287 |
| 3/8 F | 10.287 | 30.48 | 1.7145 |
| 1/2 F | 13.716 | 40.64 | 2.286 |

Preset list: sizes of the step.parts catalogue (MIT), see `library/NOTICE.md`.

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curl -o part.py "https://pythonparts.org/p/steve/inch-flat-washer/v/1.1.0/raw/part.py"

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part.py
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README.md
bundle.tar.gzthe package, as published

curl "https://pythonparts.org/api/v1/parts/steve/inch-flat-washer/1.1.0"

The version's JSON (parameters, presets, files); add /build?name=value for a build at other values.

About this part

steve58 parts

Profile

Steel (generic)Carbon & alloy steels · Custom finish · 7.9 g/cm³

Mass: 2.06 g

At the parameters shown in the viewer.

License: MIT

Permissive: use, change and sell it; keep the copyright notice.

Runtime: STEVE
Built with: CadQuery 2.9.0.dev0
Published: Nov 1, 2026
Downloads: 0
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Stars: 0
Bundle: 0995dac1d641…

#fastener #washer #flat-washer #plain-washer #fender-washer #sae #uss #asme-b18-22-1 #asme-b18-21-1 #inch

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Type A plain washer of ASME B18.21.1-2009 (formerly B18.22.1-1965, same table), narrow (N, the "SAE" series) and wide (W, the "USS" series), for #0 to 1/2 in screws. A flat ring at the table's nominal inside diameter, outside diameter and thickness. Also fender washers (F, large outside diameter) for #0 to 1/2 in screws, measured from step.parts' published models (MIT): no standard covers fender washers. It sits on the XY plane, centred on the origin (the model is in millimetres). Dimensions from the Type A preferred sizes table (see the README).

Plain washer, inch (ASME B18.21.1 / B18.22.1 Type A)

Geometry

A flat ring at the table's nominal inside diameter ID, outside diameter OD and thickness T. It sits on the XY plane, centred on the origin.

Parameters

Parameter	Meaning
`size`	Screw size and series: `1/4 N` (narrow, SAE), `1/4 W` (wide, USS), ...; `#0` to `#10` have one series; `#0 F` to `1/2 F` fender washers
`material`	`steel` (carbon steel, zinc plated), `stainless-18-8` (304), `stainless-316`

Source

Type A plain washers, preferred sizes: inside diameter, outside diameter and thickness, basic values.

ASME B18.21.1-2009 (R2016), Washers: Helical Spring-Lock, Tooth Lock, and Plain Washers (Inch Series), Type A plain washers, preferred sizes, as reproduced at https://amesweb.info/Fasteners/Washers/Type-A-Plain-Washers-Dimensions-Chart.aspx. This edition names the three smallest rows No. 0, No. 2 and No. 4.
The same values in ANSI/ASME B18.22.1-1965 (R1998), Plain Washers, Table 1A: https://engineersedge.com/plain_washers.htm, https://www.globalfastener.com/standards/detail_1111.html (that edition leaves the size column of the 0.078, 0.094 and 0.125 in rows blank).
B18.22.1 was consolidated into B18.21.1 (ASME: https://www.asme.org/codes-standards/find-codes-standards/b18-21-1-washers-helical-spring-lock-tooth-lock-plain-washers). The presets name ASME B18.22.1, the designation the catalogue uses; the values are those of both editions.

Inch values as in the table; the model converts them to millimetres (1 in = 25.4 mm).

Size	ID	OD	T
#0	0.078	0.188	0.020
#2	0.094	0.250	0.020
#4	0.125	0.312	0.032
#6	0.156	0.375	0.049
#8	0.188	0.438	0.049
#10	0.219	0.500	0.049
1/4 N	0.281	0.625	0.065
1/4 W	0.312	0.734	0.065
5/16 N	0.344	0.688	0.065
5/16 W	0.375	0.875	0.083
3/8 N	0.406	0.812	0.065
3/8 W	0.438	1.000	0.083
7/16 N	0.469	0.922	0.065
7/16 W	0.500	1.250	0.083
1/2 N	0.531	1.062	0.095
1/2 W	0.562	1.375	0.109

Sources: fender washers

step.parts, asme_fender_washer_<size>_simple for #0-80 to 1/2-13 (https://www.step.parts, repository https://github.com/earthtojake/step.parts, commit c6113328, catalog/step/): step.parts' own "analytic simplified" models, original project material under the repository's MIT licence (© 2026 earthtojake).

Size, mm:

Size	ID	OD	T
#0 F	1.646	4.8768	0.45
#2 F	2.3592	6.9901	0.45
#4 F	3.0724	9.1034	0.5121
#6 F	3.7856	11.2166	0.6309
#8 F	4.4988	13.3299	0.7498
#10 F	5.212	15.4432	0.8687
1/4 F	6.858	20.32	1.143
5/16 F	8.5724	25.4	1.4287
3/8 F	10.287	30.48	1.7145
1/2 F	13.716	40.64	2.286

Preset list: sizes of the step.parts catalogue (MIT), see library/NOTICE.md.

1.1.0 Latest Nov 1, 2026 · 1 day ago

Fender washers (F) for #0 to 1/2 in screws added, measured from step.parts' published models (MIT); Type A sizes unchanged.

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steve/inch-flat-washer

Plain washer, inch (ASME B18.21.1 / B18.22.1 Type A)

Geometry

Parameters

Source

Sources: fender washers

Plain washer, inch (ASME B18.21.1 / B18.22.1 Type A)

Geometry

Parameters

Source

Sources: fender washers

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