Horizontal Vs Vertical Milling: Which Is Best For Your Job?

At Istar Machining, we know that picking the right milling machine can make or break your project. Let’s look at how horizontal milling and vertical milling are different.

What is Milling?

Milling is when we cut metal or other stuff using spinning tools. We make parts for cars, planes, and many other things.

Two Main Types of Mills

There are two big types of milling machines:

Horizontal mills
Vertical mills

The main difference is how the spindle (the part that holds and spins the cutting tool) is set up.

Horizontal Milling Explained

In a horizontal mill, the spindle is set up like this:

The spindle lays flat (like a sleeping person)
It is parallel to the ground
It uses tools called arbor-mounted cutters
The cutters spin sideways

![Horizontal milling machine diagram]

At Istar Machining, our CNC horizontal machining services use these machines for big jobs.

Vertical Milling Explained

In a vertical mill, the spindle is set up like this:

The spindle stands up (like a standing person)
It is perpendicular to the worktable
It looks a lot like a drill press
The cutters spin up and down

![Vertical milling machine diagram]

You can see our vertical milling work at Istar Machining for many detailed jobs.

Key Differences in How They Work

Part	Horizontal Mill	Vertical Mill
Spindle Direction	Side to side	Up and down
Tool Holder	Uses arbor	Uses collet or chuck
Machine Size	Bigger	Smaller
Space Needed	More shop space	Less shop space

When to Use Horizontal Milling

Horizontal mills are best for:

Big cuts in hard stuff like steel or iron
Using many cutters at once (gang milling)
Making T-slots (special grooves)
High-volume jobs where you make lots of the same part
Heavy-duty work on big parts

Our team at Istar Machining uses horizontal mills for automotive CNC machining when making strong, big parts.

When to Use Vertical Milling

Vertical mills are best for:

Making holes and slots
Doing fine detail work
Small-batch jobs or one-of-a-kind parts
Complex shapes with lots of details
3D work that needs careful cuts

For CNC prototype machining, our Istar Machining pros often choose vertical mills.

Price Differences Between Mills

Let’s talk about cost:

Horizontal mills cost 40-50% more money to buy
Vertical mills are 30-50% cheaper
Horizontal mills cost more to fix and keep running
Vertical mills are simpler and cost less to take care of

Speed and Production Rates

When it comes to how fast they work:

Horizontal mills cut material 20-30% faster
Horizontal mills are better for making many parts quickly
Vertical mills work more slowly but with more care
Vertical mills are better for jobs where being exact is more important than being fast

Comparing Uses Across Industries

Different jobs need different mills:

Industry	Horizontal Mill Use	Vertical Mill Use
Aerospace	Not used much (except for big flat parts)	Used for titanium parts and exact prototypes
Automotive	Used for engine blocks and big car parts	Used for brake parts and small connectors
Tool & Die	Not used much (not precise enough)	The top choice for making molds with CNC
Construction	Used for steel beams and rail parts	Not used much (too small for big construction)

At Istar Machining, we select the right mill for each job to make sure our CNC machining service gives you the best results.

How Much Material They Can Remove

Material Removal Rate is how fast a mill can cut away material:

Horizontal mills can remove up to 45 cubic inches per minute from cast iron
Vertical mills can remove about 25 cubic inches per minute from the same material

This means horizontal mills can do “rough” work much faster!

What It Costs to Run Each Machine

Running these machines costs money:

Horizontal mills cost $250-$400 per hour to run
Vertical mills cost $150-$250 per hour to run

Small shops pick vertical mills 85% of the time because they cost less.

How Precise Each Type Can Be

When it comes to making exact parts:

Vertical mills are better for doing fine, exact work
Horizontal mills are less good at complex 3D shapes
Vertical mills can more easily do multi-axis CNC work
Horizontal mills are limited to cutting in the horizontal plane

For parts that must be perfect, we at Istar Machining often use our precision milling services.

Pros and Cons List

Horizontal Milling Pros:

Cuts material faster
Better for big production runs
Can use multiple cutters at once
Good for heavy-duty work
Works well on hard metals

Horizontal Milling Cons:

Costs more to buy and run
Takes up more space
Harder to learn how to use
Not as good for fine detail work
Limited to simpler shapes

Vertical Milling Pros:

Costs less to buy and run
Takes up less space
Easier for new people to learn
Better for precise work
Can make complex 3D shapes

Vertical Milling Cons:

Cuts material more slowly
Not as good for big production runs
Limited in how much material it can remove at once
Not ideal for the biggest, heaviest parts

How to Choose the Right Mill

Ask yourself these questions:

How much money can I spend? (Vertical mills cost 30-50% less)
How big are the parts I’m making? (Big parts = horizontal mill)
What’s more important: speed or precision? (Speed = horizontal, Precision = vertical)
Do I need to make complex 3D shapes? (If yes, vertical mill is better)
How much space do I have in my shop? (Small space = vertical mill)

In today’s market:

Vertical mills make up about 70% of all milling machines
Horizontal mills make up about 30% of all milling machines
Vertical mills are the top choice in aerospace, electronics, and small shops
Horizontal mills are preferred in heavy industries like oil & gas and construction

The Role of CNC in Modern Milling

Both types now come with CNC (Computer Numerical Control):

CNC lets computers control the machines
Both vertical and horizontal CNC mills can make parts without a person watching all the time
CNC vertical mills are often used at Istar Machining for CNC milling of complex parts
CNC horizontal mills can be set up to run for hours making the same part

Real-World Applications

Here are some real examples of when to use each type:

Horizontal Mill Uses:

Making car engine blocks
Cutting big T-slots in metal plates
High-volume production of simple metal parts
Heavy work on cast iron or steel
Gang milling operations with multiple cutters

Vertical Mill Uses:

Making aerospace parts with tight tolerances
Creating medical device components
Prototyping new product designs
Making molds for plastic injection
Detailed work on smaller metal parts

Final Thoughts

To sum it up:

Vertical mills work best for 80% of small to medium projects
Horizontal mills are the kings of heavy industry production
Istar Machining uses both types to give you the best results
The right choice depends on your specific job needs

When you work with Istar Machining, we help you pick the right machine for your project. We offer both CNC vertical machining and horizontal options to meet all your needs.

Make the Right Choice for Your Project

Now that you know the big differences between horizontal and vertical milling, you can make a smart choice for your next project.

Remember that at Istar Machining, we have experts in both types of milling. We can help you decide which is best for your specific needs.

Need help with your next milling project? Contact us today to learn how our CNC milling service can bring your ideas to life!

[^1]: Information from American Micro Inc. resources on vertical vs. horizontal milling [^2]: Data from CNC Masters comparison of vertical and horizontal milling techniques [^3]: Statistics from Fractory’s analysis of horizontal vs. vertical milling applications [^4]: Industry adoption patterns from Swanton Weld’s horizontal vs. vertical milling guide [^5]: User experiences from Hobby-Machinist forums on horizontal vs. vertical milling preferences