Close menu
Hello, Sign in
Account & Orders
Deals

Reach new customers!
Sell on our marketplace

Shop by Material
Metals

Alloy Steel

Aluminum

Beryllium Copper

Brass

Bronze

Carbon Steel

Copper

Dura-Bar® Cast Iron

Lead
Magnesium

Nickel

Nickel Silver

Pewter

Stainless Steel

Titanium

Tool Steel

Tungsten Carbide

Zinc
Other Materials

Plastics

Rubber

Carbon Fiber

Fiberglass

Kevlar

Graphite

Wood

New! Coal

New! Machinable Wax
Non-Raw Materials

3D Printing

Fittings

Abrasives
Shop by Shape
Long Product (Bar)

Round

Square

Rectangle

Angle

Channel

Hex

Hollowbar

Half Oval

Half Round
T-Bar

T-Slot

Drill Rod

I-Beam

Round Rod

Threaded Rod

Key Stock
Flat Product

Sheet & Plate

Strip

Precision Blanks

Circles

Expanded

Perforated

Tread (Diamond) Plate

Foil

Wire Mesh
Tube

Round

Pipe

Square

Rectangle

Coil

Hollowbar

Streamline Tube

New! EZ Tube

New! Hypodermic Tube
Other

Ball

Decorative

Pipe Fittings

Protoboxes

Sample Pack

U-Edge

Cable and Wire
Build Accessories
3D Printing

Metal 3D Printing Filament

Ceramic 3D Printing Filament

Glass 3D Printing Filament

3D Printing Accessories
Fittings

Pipe Fittings

Tube Fittings
Framing Systems

Unistrut Systems

T-Slot Systems

EZTube
Precision Products

Centerless Ground Accurod®

Drill Rod

Ground Flat Stock

Precision Blanks
Cable and Wire

Uninsulated Wire

Hook-Up Wire

Cable Assemblies

Magnet Wire

Wire and Cable Accessories
Razor Wire
New! Rewards
OLM Rewards

About Rewards

Sign In for Rewards
Knowledge Hub
Articles

Working With Metal

Understanding Materials

Applications

Projects

Maker Spotlight

Online Metals Exclusive Content
Reference Guides

Product Guides

Temper Guide

Tolerances

Hardness Conversion Table

Thickness Conversion Table

Fraction Conversion Table

Melting Points of Materials

Weight Calculator
Videos

Made with Metals

Materials Talk

DIY & How-to Projects

The Best of Online Metals
Quality

Mill Test Reports (MTR)

MSDS
Business Solutions
B2B Purchasing

Credit Terms

Tax and Banking

Quality
Partner Services

Become an Affiliate

Sell on Online Metals

Paperless Parts Viewer
Fabrication Services

Production Waterjet

Laser Cutting

Cutting and Finishing Services
Industries Served
Industries Served

Aerospace

Architectural

Automotive/Motorsports

Bicycles/Cycling

Bladesmithing

Defense

Education/Schools

Marine

Prototyping and R&D
Robotics

Welding

Close menu

Shop all Products

Aluminum
Stainless Steel
Steel
Copper
Brass
Bronze
Nickel
Titanium
Other Metals
Other Raw Materials
Manufacturing Accessories
Finishing Products

Shop Aerospace Materials

Open for Orders 24/7!

Get a Quick Quote!

Deals

Get a Quick Quote!

Home
Long Products
Square Bar
Tool Steel
Tool Steel Square Bar
Tool Steel Square Bar O1 Oversize

square-bar-large-new-min-4superZoom

Tool Steel Square Bar O1 Oversize

-8 Products

Tool Steel O1 Product Guide

| Tool Steel O1 Square Bar Tolerances

Ground Oversize Tool Steel Square Bar is ground to a maximum surface finish of 40 Ra with tolerances of + 0.010" to + 0.015" on the height and the width. This material is produced from cross-rolled sheet or plate which produces a finer grain size and enhances the toughness of the material. Lastly, tool steel rectangle bar is 100% free of decarburization is completely spheroidized throughout.Tool Steel Square Bar Oversize O1 is an oil-hardening, general purpose tool steel that holds its size and shape with excellent accuracy when being heat treated. While not as strong or wear resistant as A-2 or D-2, it experiences significantly less distortion during the heat-treating process.

Sort by

Displaying 1 - 8 of 8 results

25 Per Page
50 Per Page
100 Per Page

Size
Price:Low to High
Product Name: A to Z
Product Name: Z to A
Relevance
Price:High to Low

Sort by

Displaying 1 - 8 of 8 results

25 Per Page
50 Per Page
100 Per Page

Close

Filters

Production Method

Ground Oversize

Unit of Measure

inch

seller

Onlinemetals.com

Material

Tool Steel

Alloy/Type

O1

Shape

Bar-Square

Can't find what you need?

Contact our experienced US-based customer service team for hard-to-source materials.

%7B%22item_id%22%3A%2212429%22%2C%22item_name%22%3A%223%2F16%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

3/16" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12429

3/16" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12429

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.1875"

See all available dimensions for this product

Select a Cut Size for Price Select a Cut Size

36″ (3 ft.) - $78.50 ea.
Buy 4 at the 12 ft price!

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

$78.50 ea.

$78.50 for 1

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212431%22%2C%22item_name%22%3A%221%2F4%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

1/4" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12431

1/4" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12431

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.25"

See all available dimensions for this product

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212433%22%2C%22item_name%22%3A%225%2F16%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

5/16" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12433

5/16" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12433

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.3125"

See all available dimensions for this product

Select a Cut Size for Price Select a Cut Size

18″ (18 in.) - $49.35 ea.
36″ (3 ft.) - $81.60 ea.
Buy 4 at the 12 ft price!

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

$49.35 ea.

$49.35 for 1

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212435%22%2C%22item_name%22%3A%223%2F8%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

3/8" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12435

3/8" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12435

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.375"

See all available dimensions for this product

Select a Cut Size for Price Select a Cut Size

18″ (18 in.) - $62.10 ea.
36″ (3 ft.) - $102.65 ea.
Buy 4 at the 12 ft price!

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

$62.10 ea.

$62.10 for 1

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212437%22%2C%22item_name%22%3A%221%2F2%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

1/2" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12437

1/2" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12437

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.5"

See all available dimensions for this product

Select a Cut Size for Price Select a Cut Size

18″ (18 in.) - $70.90 ea.
36″ (3 ft.) - $117.10 ea.
Buy 4 at the 12 ft price!

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

$70.90 ea.

$70.90 for 1

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212440%22%2C%22item_name%22%3A%225%2F8%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

5/8" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12440

5/8" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12440

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.625"

See all available dimensions for this product

Select a Cut Size for Price Select a Cut Size

18″ (18 in.) - $92.73 ea.
36″ (3 ft.) - $153.41 ea.
Buy 4 at the 12 ft price!

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

$92.73 ea.

$92.73 for 1

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212443%22%2C%22item_name%22%3A%223%2F4%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

3/4" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12443

3/4" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12443

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 0.75"

See all available dimensions for this product

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

Sign in required - Sign In Now

%7B%22item_id%22%3A%2212448%22%2C%22item_name%22%3A%221%5C%22+Tool+Steel+Square+Bar+O1+Ground+Oversize%22%2C%22item_brand%22%3A%22%22%2C%22item_category%22%3A%22Tool+Steel%22%2C%22item_category2%22%3A%22Bar-Square%22%2C%22item_category3%22%3A%22O1%22%2C%22item_category4%22%3A%22%22%2C%22item_category5%22%3A%22Ground+Oversize%22%2C%22item_category6%22%3A%22%2F%22%2C%22item_category7%22%3A%22%22%2C%22item_category8%22%3A%22false%22%2C%22item_category9%22%3A%22false%22%2C%22item_list_id%22%3A%22%22%2C%22item_list_name%22%3A%22%22%2C%22item_variant%22%3A%22%22%2C%22price%22%3A%22%22%2C%22quantity%22%3A%22%22%7D

1" Tool Steel Square Bar O1 Ground Oversize -
Part #: 12448

1" Tool Steel Square Bar O1 Ground Oversize -

Part #: 12448

Click for more details

tool-steel-square-bar-o1-oversize-1superZoom

Compare

Dimensions

Height: 1"

See all available dimensions for this product

Select a Cut Size for Price Select a Cut Size

18″ (18 in.) - $171.77 ea.
36″ (3 ft.) - $283.94 ea.
Buy 4 at the 12 ft price!

Save on shipping!

You can select smaller lengths and switch from freight to standard shipping and save!

How does selecting smaller lengths reduce shipping costs?

Reducing your order from an oversize item that requires expensive freight services to a smaller bundle makes it eligible for less expensive (and faster!) standard shipping services.

*Material tolerances will remain +/- 0.125".

Best shipping value:

Single Heat Lot Required

Why are heat lots important?

Heat lots ensure consistent metal properties, full traceability, and quality control, which are critical for precision and reliability in your projects.

By selecting "Single Heat Lot Required" option, we ensure all cut pieces are sourced from a single heat lot for consistency in material characteristics.

QTY

QTY

$171.77 ea.

$171.77 for 1

Sign in required - Sign In Now

Can't find what you're looking for?

Contact us for a custom quote

Close

You Have Added QTY to Your Cart

Product Name Part #

Placeholder for future product image

Dimensions

Size:

Go To Cart Continue shopping

Close

Up to 4 products can be compared

You have reached the maximum number of items to compare. Remove an item to change assortment.

Knowledge
Hub

Application Hub
Article Hub
Reference Tool & Guide Hub
Video Hub

quick tools icon

Quick Tools

Metal Weight Calculator
Product Guides
Hardness Conversion Table
Melting Points of Metal
Made With Metals Gallery

Partner Services

Become a Marketplace Seller
Affiliates Program
Net 30 Credit Terms
W9 Form & ACH Payment Setup

Terms of Use

Cookie Preferences
Privacy Policy
Returns & Price Matching
Site Accessibility
Terms & Conditions
Rewards Program
Rewards T&Cs

About Us

Careers
Contact Us
Environmental Initiatives
Location & Hours
Our Story
Shipping Process
ISO & Quality
Reviews
Site Updates

Application Hub
Article Hub
Reference Tool & Guide Hub
Video Hub

Quick tools icon

Weight Calculator
Product Guides
Hardness Conversion Table
Melting Points
Made With Metals Gallery

Partner Services

Become a Marketplace Seller
Affiliates Program
Net 30 Credit Terms
W9 Form & Vendor Information

Cookie Preferences
Privacy Policy
Returns & Price Matching
Site Accessibility
Terms & Conditions
Rewards Program
Rewards T&Cs

Careers
Contact Us
Environmental Initiatives
Locations & Hours
Our Story
Shipping Process
ISO & Quality
Reviews
Site Updates

ALL CONTENT © ONLINEMETALS.COM 1999-2025. ALL RIGHTS RESERVED.

Email: sales@onlinemetals.com

Close

Sign In

sitelogo

A link to reset your password has been sent to your email address.

Follow the instructions in the email to reset your password.

Your password has been updated successfully.

Please use it when signing in below

Sign In to request a quote * Required fields

Email address*

Password*

Password guidelines

Minimum 8 characters
Minimum three character classes must be used from below:
- Uppercase letters (A-Z)
- Lowercase letters (a-z)
- Numbers (0-9)
- Special characters: ~!@$%^&*_-+=`|\(){}[]:;"',.?/

Forgot your password?

Keep me signed in

Keep me "signed in" info

Choosing "Keep me signed in" reduces the number of times you're asked to sign in on this device

To keep your account secure, use this option only on your personal devices.

Don't have an account yet?

Close

Sign In

Welcome,
!

Enter Your Password *

Password guidelines

Minimum 8 characters
Minimum three character classes must be used from below:
- Uppercase letters (A-Z)
- Lowercase letters (a-z)
- Numbers (0-9)
- Special characters: ~!@$%^&*_-+=`|\(){}[]:;"',.?/

Keep me signed in

Keep me "signed in" info

Choosing "Keep me signed in" reduces the number of times you're asked to sign in on this device

To keep your account secure, use this option only on your personal devices.

Continue modifying your quoted cart?

Please note: If you choose to continue modifying your order, you will lose quoted pricing.

Your cart will adjust to regular pricing of our products, as found on our site.
If you wish to go back to your original quoted pricing, it will be available on your quote history page in your account until it expires.

Or