STEPCRAFT D840 CNC Review[2023]: Solid Choice?

STEPCRAFT D840 CNC Review[2023]: Solid Choice?

STEPCRAFT D840 CNC Review[2023]: Solid Choice?

Stepcraft D.840 is a CNC router from the brand Stepcraft CNC systems that is very popular among hobbyists.

Stepcraft sells three types of CNC Machines.

The first one is the D series, which comes in four different sizes and is primarily for CNC hobbyists and small businesses. 

The second type is the Q series which is essentially for CNC manufacturing and serial production. 

The third type is the M series, a milling CNC machine primarily known for its multi-tool capability.

The D.840 that I review in this article is the largest one in the D Series and is used by creative professionals and hobbyists working on medium to large-scale projects.

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For this review, I evaluated the CNC router for its build, quality, linear motion components, material capability, electronics, ease of use, and support.

Size of D840 CNC

The model name D.840 refers to the length on the Y-axis which is 840 mm.

The overall footprint of the machine is 40.2” x 29.8” x 21.5” and it weighs around 70 lbs.

It is better to go for a welded table for placing the machine. However, you can use any desk of the proper size, but make sure the table is sturdy enough.

The work area that you get is 23.4" x 32.8" with a Z-axis travel of 5.2". The maximum thickness of material that can pass under the gantry is 5.75".

Material Capability

It can mill a variety of materials such as plastics, hardwood, softwood, and PCB. In addition, it can also mill PVC, polyamides, Plexiglas, PP, and aluminum. 

D840 Milling Wood
D840 Milling Wood

For better results with aluminum, the use of lubricants is recommended but not mandatory. However, you have to be cautious of the lubricant seeping into the wasteboard.

You cannot use this machine for cutting non-ferrous metals like steel as this is not the recommended machine for the job.

The cutting speed will depend on the material you cut and the spindle you choose, but this machine can move fast.

If you use a 25,000 RPM spindle for cutting MDF on this router, you can achieve feed rates of roughly 118 ipm at 0.2” depth-of-cut.

STEPCRAFT provides a clamping kit with D.840 which you can use to hold down your workpieces. Alternatively, they also have an optional aluminum T-bed for work holding.

Chassis/Frame of D.840

Eclosed design of STEPCRAFT D840
Eclosed design of STEPCRAFT D840

The frames are made of extruded aluminum. STEPCRAFT provides its own custom-made extrusions which are durable and steady.

If looks matter to you, the D.840 is one of the most sleek-looking CNC routers that I have come across.

The frame is powder-coated making the CNC resistant to wear and tear from usage. 

The screws and nuts are made from stainless steel and high-quality aluminum which adds to the rigidity and long life of the router.

One of the excellent design features is the covered moving parts. Almost all moving parts are protected from dust and debris making maintenance much easier and infrequent. 

The Y-axis is covered with silicon flaps which prevent dust from entering the linear motion components.

The effort STEPCRAFT put into making the machine dustproof makes it a good choice for cutting materials that produce dust-like wood, polycarbonate, and other soft materials.

HPL is used for making the wasteboard. The multiple layers of laminate prevent flexing.

Overall, the material and build quality of the machine allow it to achieve a repeatability of around 0.0019” which is on the higher side when compared with other CNC routers in the same price range.

Linear Motion

Lead screws, roller wheels, aluminum linear guides on STEPCRAFT D840
Lead screws, roller wheels, and aluminum linear guides on STEPCRAFT D840

All three axes use a lead screw mechanism for linear motion. The lead screws have a backlash between 0.001” and 0.003” which is correctable using the control software.

STEPCRAFT has used Swiss-made lead screws on the D.840 which are long-lasting and reliable.

The gantries are guided by the STEPCRAFT custom aluminum extrusions which support and guide roller wheels on the gantry.

Spindles for D840

Spindle on D840
Spindle on D840

STEPCRAFT does not tie you down on spindle choices and allows you to use a spindle of your choice.

This means the kit ships without a spindle.

However, you can add a spindle from the list of spindles that STEPCRAFT offers for an additional amount.

Stepcraft D.840 is compatible with following spindles:

  • Dremel 4000 
  • Proxxon IBS/E 
  • Dewalt DW611 
  • Bosch Colt 
  • Kress 800 FME

I have provided a quick summary of these spindles in the table below:

Speed (RPM)PowerShank SizeFeatures
STEPCRAFT HF5005,000-20,000500 W1/8" - 3/16"Manual/Auto speed control,
ATC available
STEPCRAFT MM-10004,000-25,0001,000 W1/8" - 1/4"Manual speed control,
ATC available
STEPCRAFT MM-1000 DI4,000-25,0001,000 W1/8" - 1/4"Manual/Auto speed control,
ATC available
Dremel 4000 5,000-35,000200 W1/8"Manual speed control
Proxxon IBS/E 5,000-20,000100 W1/8" - 1/32"Manual speed control
Dewalt DW611 16,000-27,000960 W1/8" - 1/4"Manual speed control
Bosch Colt 16,000-35,000750 W1" - 5/16"Manual speed control
Kress 800 FME10,000-29,000800 W1/8 "Manual speed control

Quick summary of the spindles offered by STEPCRAFT for D.840 CNC

Stepcraft provides STEPCRAFT MM-1000 DI (standard version) and STEPCRAFT MM-1000 DI with automatic tool changer as optional accessories to include in the kit at the time of purchase for some extra money.

However, you can select any other spindle that meets your requirements. Make sure to purchase the proper spindle mount for the spindle you choose.

Controller and Electronics

Stepper Motors

Each axis of D.840 is controlled with the help of a stepper motor and each motor can draw a maximum of 2 A.

The Y-axis is moved by a dual stepper motor configuration, which is an upgrade from their previous D.840 version.

The dual Y-axis motor prevents racking of the gantry and allows the machine to move at 40% faster speeds than its older versions.


D.840 uses an Arduino board flashed with GRBL firmware as the controller.

You can connect the controller to your computer using a USB cable. STEPCRAFT also offers a USB to ethernet converter at an additional charge.

The D.840 also comes with homing sensors on all three axes which make homing and zeroing the device an easy task.

The entire kit will draw around 3A of current and it can work with any regular wall socket. You must also factor in the current draw of the spindle you choose.

The controller is compatible with UCCNC, WINPC-NC, Linux CNC, Mach 3, and Mach 4 control software programs.

Software in D840 CNC

UCCNC software interface
UCCNC software interface

You get the UCCNC control software with D.840 for controlling the CNC router.

UCCNC has a minimalistic and clutter-free user interface that is easy to learn.

It can handle up to 6-axis machining. However, D.840 can only handle a maximum of 4 axes.

You will need a Windows PC to install and run UCCNC.

If you want to use Mac or Linux computers you should look at other software for CNCs like Mach 3/4 or Linux CNC.

The software included in the kit is purely machine control software. You will need additional software for creating designs and generating G-code.


STEPCRAFT offers multiple accessories for the D.840 which makes it a versatile CNC machine.

The accessories include 3D Printer Head, hot wire cutter, fourth rotary axis, milling bath, and a laser engraver.

3D Printer Head

3D print head PH-40 for D840
3D print head PH-40 for D840

The 3D Printer Head is for 3D printing. It drives the heated plastic filament through the nozzle to extrude plastic.

It has a dual feed that allows you to extrude two materials simultaneously.

This accessory costs around $600, and you can consider it if you need a CNC router and occasionally need a 3D printer.

Hotwire Cutter

Hot wire cutter for D.840
Hotwire cutter for D.840

It is an accessory that allows you to cut polystyrene foam. 

The device consists of a thin metal wire, usually made of nichrome alloy, which is heated to approximately 200°C. 

The wire is passed through the material, and the heat from the wire vaporizes the material upon contact.

If you have to handle large volumes of projects and have to make repeated cuts then this would be a nice addition.

It costs around $130 and for small one-off jobs with foams, the return on investment is not worth it.

Laser Engraving Head DL445

Laser Engraving Head DL445
Laser Engraving Head DL445

This will turn your CNC router into a CNC laser engraver that you can use to engrave on a wide range of materials.

It uses a 3-watt laser and comes with a control unit that lets you integrate it with the existing controller of the D.840.

This upgrade will cost you around $700 and you can purchase it from the STEPCRAFT official website.

4th Axis System

4th axis system for D.840
4th axis system for D.840

This upgrade will add an additional fourth rotary axis to your D.840.

You need this upgrade if you want to process cylindrical workpieces like chess pieces and baseball bats.

The installation is easy, however, you will need a T-slot bed for better performance and easy mounting.

The kit comes with a 3-jaw chuck, the controller, and a tailstock. It will cost you around $700 and can be purchased from the official website of STEPCRAFT.

Milling Bath

Milling bath for D.840
Milling bath for D.840

It is basically a swimming pool for your workpiece, where it can cool down while it is being cut.

The milling bath will replace the bed on the D.840 and you can fill it with water or other liquid.

It is a good accessory for cutting plexiglass, thermoplastics, carbon, and aluminum.

Additionally, the bath will also prevent the dust and debris from spreading and it also improves the life of the router bits or end mills you use.

You can purchase it from the official website of STEPCRAFT for around $320.

Assembling D840 CNC

STEPCRAFT D840 self assembly kit
STEPCRAFT D840 self-assembly kit

The assembling is quite simple owing to the clear and detailed Easy Build Manual that STEPCRAFT provides. 

You can assemble the CNC kit within 3 to 4 hours.

Also, you have various build guides available on YouTube which simplify the process even more.

There are no pre-assembled components in the kit and you have to assemble the components, this allows you to learn each and every aspect of your CNC router and will help in troubleshooting in the future.

However, if you want a CNC router that can start cutting straight out of the box, STEPCRAFT also offers an assembled version of D.840.

It will cost you around $500 more than the DIY version but it comes assembled, calibrated, and tuned.

You will be good to go in minutes.

STEPCRAFT will custom ship the assembled machine on custom-made crates and all you need to do is place it in your shop.


The STEPCRAFT community is a buzzing one and offers keen insight for any queries that you might have.

Since most of the people who work with the D.840 are beginners and small businesses, there is a large community at hand.

Also, the STEPCRAFT official forum is a great place to gather information and get answers for any problem you might have.

In addition, you have a Facebook community page where you can share your views and interact with other people who are working with the same machine.

Customer Support

STEPCRAFT follows the German-engineered American-Built philosophy. The machines are built in the US according to the CNC building techniques developed through German engineering.

STEPCRAFT is well known for its US-based Customer Support. The dedicated phone line is a great place to get your queries cleared. 

They also have experts available on the same phone line to answer all your questions related to the machine.

The product comes with a warranty of two years which is a testament to its build quality.

The company, STEPCRAFT, is based in Torrington, Connecticut.

Final Thoughts

Overall, the STEPCRAFT D.840 is a sturdy and well-built machine and has been serving its users well for some time.

The wide range of accessories makes it a good choice if you need a CNC machine that can 3D print, mill, cut, and engrave.

The D840 is Engineered in Germany and Built-in USA, giving it the best of both worlds.

Frequently Asked Questions (FAQ)

Does STEPCRAFT D.840 support tiling feature?

Yes, you can use the tiling feature on D.840 as both the ends on the Y-axis are open. This theoretically allows you to have an infinite X-axis length for the workpiece you use. However, the Y-axis length is limited to 33 inches and hence you cannot cut full size 4x8 sheets.

About John Abraham

Hey I'm John. I write about Manufacturing, Metalworking, CNCs and Lasers at Mellowpine. If you have any questions related to CNCs or Lasers, I'd be happy to answer them. Reach me at mail@mellowpine.com

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John Abraham

Hey I'm John. I write about Manufacturing, Metalworking, CNCs and Lasers at Mellowpine. If you have any questions related to CNCs or Lasers, I'd be happy to answer them. Reach me at mail@mellowpine.com


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