DIY 3D Printed CNC Machine Can Cut Metal – Complete Build | HTMCNC

In this tutorial we will learn how to build a CNC machine with a step-by-step guide so you can easily build one on your own. 

This is a Fully 3D Printed CNC machine or a CNC router that I designed with two specific goals in mind, to be as rigid as possible, and to be as simple as possible to build.

Overview

Being rigid directly affects the performance of the machine and besides engraving and cutting wood, I wanted this CNC router to be capable of engraving and cutting aluminum. It turned out it can do that quite confidently.

Here’s an example of machining a propeller out of aluminum. With just a little bit of sanding the propeller surface finished turned out super smooth.

I also did some accuracy tests by cutting various shapes out of aluminum. If we use appropriate feeds and speeds, we can get the aluminum parts within 0.05mm accuracy.

I think that’s a descent accuracy considering it’s a 3D printed CNC machine, using a trimmer router, and an Arduino UNO and GRBL for the motion-control. 

Engraving aluminum is a breeze. I did a few keychains engravings with very small details under 1mm, and they came out great.

I also tried engraving brass which also turned out great.

This 3D printed CNC router is even capable of cutting steel.

My second goal for this CNC machine was to be as simple as possible to build, which meant that I didn’t want to use any power tool for making the machine, no cutting aluminum extrusions with a saw, no drilling, no tapping…. Nothing.

Literary, you can build this CNC machine with just a set of Allen keys, because I specifically designed it to utilize just standard components that can be easily sourced from sites like Amazon, AliExpress or any other store of your choice. So, it’s almost like a DIY kit that you just have to assemble it. Below you can find the complete list of components needed for this CNC build.

Though (there is a caveat of course), you need a 3D printer in order to make this CNC machine, but I don’t think it’s a big deal, as if you don’t have one, nowadays there are so many 3D printing services from where you can easily get the 3D printed parts for it.

I’m calling it a fully 3D printed CNC machine, as the entire CNC structure is based on 3D printed parts, including the X and Z-axis plates, the router mount and even the ball screw bearing blocks are 3D printed.

The design was optimized to get the most out of the fact that we can easily print complex parts with a 3D printer. In combination with some 20x40mm aluminum extrusions, 15mm linear rails, and 16mm ball screws, I think I managed to get a decent performance out of it. It’s capable of engraving and even precision parts out of aluminum, and the wood projects are a breeze; it can easily cut any hardwood, and the wood engravings are just perfect. Just take a look at this 340x340mm 3D relief in beech hardwood. It looks stunning.

The work area is 450x350x110mm, but the coolest part is that we can easily scale this CNC machine.

We can simply use longer components for some of the aluminum extrusions, the linear rails and the ball screws, and we instantly get larger work area while all other components and the assembly process itself remain the same.

Below can find details about which components define the work area of the machine, so you can get your desired work area by choosing the right components.

3D Model and STL Download Files

You can view the 3D model of this DIY CNC Machine directly on your web-browser with Onshape.

You can get the 3D model of this DIY CNC Machine, as well as the STL files for 3D Printing from Cults3D.

Bill of Materials

Below is the complete list of components needed for this DIY CNC build.

The given dimensions are for the exact same size as the CNC I demonstrated building with 450x350mm work area.

Component	Quantity	Purchase Links
Aluminum Extrusion 2080 – 600mm (Y-axis, Custom Length)	2	Amazon | AliExpress
Aluminum Extrusion 2040 – 600mm (X-axis Base, Custom Length)	3	Amazon | AliExpress
Aluminum Extrusion 2040 – 700mm (X-axis Gantry, Custom Length)	2	Amazon | AliExpress
Aluminum Extrusion 2040 – 200mm	2	Amazon | AliExpress
Aluminum Extrusion 2040 – 100mm	2	Amazon | AliExpress
Linear Rail HGR15 – 600mm (Y-axis, Custom Length) & (X-axis, Custom Length)	4	Amazon | AliExpress
Linear Rail HGR15 – 300mm (Z-axis)	2	Amazon | AliExpress
Ball Screw SFU1605 – 500mm (Y-axis, Custom Length)	1	Amazon | AliExpress
Ball Screw SFU1605 – 600mm (X-axis, Custom Length)	2	Amazon | AliExpress
Ball Screw SFU1605 – 300mm (Z-axis)	1	Amazon | AliExpress
Angular Contact Bearings – 7001 P5-DB A-Pair	(4 pairs)	Amazon | AliExpress
M12x1mm Locknut	4	Amazon | AliExpress
Radial Ball Bearing – 6001 – 2RS	4	Amazon | AliExpress
Corner Bracket 28x20x28mm (with suitable T-slot nuts and M5 Bolts)	18	Amazon | AliExpress
Corner Bracket 20x20x20mm (with suitable T-slot nuts and M5 Bolts)	8	Amazon | AliExpress
M5 Sliding T-nut	100	Amazon | AliExpress
M5 Hammer Head T-nut	100	Amazon | AliExpress
M4 Sliding T-nut	50	Amazon | AliExpress
M4 Hammer Head T-nut	50	Amazon | AliExpress
Stepper Motor NEMA23	4	Amazon | AliExpress
Bolts Socket Head M3x12mm – 10 M3x16mm – 5 M3x30mm – 5 M4x10mm – 5 M4x12mm – 5 M4x14mm – 60 M4x25mm – 10 M5x12mm – 50 M5x16mm – 40 M5x20mm – 40 M5x30mm – 40 M5x50mm – 25 M5x60mm – 35 M5x70mm – 5	/	Amazon | AliExpress

Disclosure: These are affiliate links. As an Amazon Associate I earn from qualifying purchases.

For the electronics components, the BOM will be in the next dedicated tutorial for the CNC control box which is coming soon.

Scaling the CNC – Custom Work Area Size

If you would like to increase the work area of the CNC you could just increase the size of the aluminum extrusions, the linear rails and the ball screws for the particular axis.

For example, in order to increase work area in the Y-axis, from 450x350mm to 450x750mm, we need to increase the length of the Y-axis aluminum extrusion, linear rail and ball screw. The difference is 750-350=300mm, so we need to add 300mm to the base lengths of this CNC machine for the Y-axis parts. That would be:

• Aluminum Extrusion 2080 – 600mm + 300mm = 900mm
• Linear Rail HGR15 – 600mm + 300mm = 900mm
• Ball Screw SFU1605 – 500mm + 300mm = 800mm

The same principle is used for scaling the work area of the machine in the X-axis. Though, there is one difference here as we would increase the gantry size, we would need to add another truss structure element.

Please note that increasing the size of the machine in the X-axis or the gantry would result in reduction of the rigidity of the whole machine, compared to the increase of the size in the Y-axis which almost doesn’t affect the rigidity of the whole machine.

Assembly

You can follow the following video for a complete step-by-step guide on how to build this DIY 3D Printed CNC machine.