Web_LongMill_12 zoom


Web_LongMill_09 zoom


5 zoom


MK2 Dimensions zoom


Web_LongMill_04 zoom


4 zoom


1 zoom


2 zoom


3 zoom


Web_LongMill_18 zoom


7 zoom


MK2 Dimensions
Full Screen

LongMill Benchtop CNC MK2

(367 customer reviews)




LongMills are expected to ship within 3-4 weeks from the time of order. Each machine is made to order. Please Note: “In Stock” means we can accept orders, but LongMill Beginner Kits are currently unavailable to ship immediately.

The LongMill MK2 is a powerful and affordable hobby CNC router perfect for any workshop. Scale it to your needs by choosing from one of its three flavors: 12×30, 30×30, and 48×30.

The machine name roughly corresponds to its cutting area in inches and each machine has 125mm (~4.9″) of Z-axis travel.

Not sure what you need to order for your LongMill? Check out the Beginners Kit.

Shipping is calculated at checkout.



Turn your ideas into a reality with the LongMill Benchtop CNC MK2

The LongMill helps you take your woodworking and fabrication to the next level. Its range of workable materials includes any species of wood, a variety of plasticssoft metals like aluminum and brass, and a variety of machinable foams and waxes for model making or metal casting.

We designed the LongMill to be the best hobby CNC router in its class, offering rigidity, and reliability. With large extruded aluminum rails, fully supported Y-axes, 1/4″ steel gantries on all axes, high power NEMA 23 motors, and high precision MG-12 type linear guides on the Z-axis, the LongMill MK2 is the most powerful CNC router in its class at its price point.

This kit comes with:

  • All rails, gantries, fasteners, lead screws, and other hardware parts to make a complete LongMill
  • All electronics, including power supply, controller, drivers, and motors.  Please Note*Power supplies are 110V only, (North America).  If you live in a country with 220V/240V power, our standard LongMill MK2 power adapter must use a transformer with a rating above 300 watts to convert their power to 110V/120V
  • Assembly instructions and resources
  • Excellent lifetime technical support during the life of your ownership

Tools and supplies needed for assembly (not included in the kit) are

    • 3/4″ MDF sheet to act as a working surface
    • An electric drill or screwdriver
    • A laptop or computer
    • A router and end mills (for purchase separate on our store)

For routers, we recommend the Makita RT0700/RT0701. It’s reliable, powerful, speed-adjustable to a large range (10-30K RPM), and its uniform outer body allows for versatile z-axis mounting. We’ve been using the Makita on our CNC machines for years. The LongMill MK2 comes free as standard with a 65mm router mount, which is compatible with the Makita RT0700/RT0701 and most variations of this router design. If you wish to use a different size router or spindle, please check out the other sizes that we offer.

*Routers that we supply will be 110V only (North America). If you live in a country that uses a different voltage, please purchase a router in your region. 

The LongMill comes with free software and is compatible with dozens of other paid and free software. Try our Toolchain Wizard to get a quick recommendation for software that may work best for you.

Additional information

Weight60 lbs
Dimensions8 × 10 × 41 in


For dimensioned drawings all of the machines, please download our PDF document. If you’d like to see some tables that our community members have built for their own machines, we’ve got a page on it here: Community Table Builds. If you’re looking to properly size a space to put your machine or are making a dedicated table, ensure that you leave enough room for the LongMills control box and any other peripherals that you might be using like a laptop, monitor, keyboard, etc. The control box is roughly 150mm x 280mm, has holes so that it can be easily screwed or mounted to any surface, and has a USB port on its left side which allows you to connect your computer to control the machine.


You can include add-ons to improve the functionality of the LongMill. These are all optional. For additional add-ons, please see our Add-On section of our store.

Makita RT0701 Router

We recommend using the RT0700/RT0701 Makita trim router with your LongMill (we only sell the 110V version). This router comes with speed control from 10,000 to 30,000RPM and has 1.25HP of power. This router is compatible with 1/4″ shank tooling and can be adapted to 1/8″ shank tooling using a 1/4″ to 1/8″ collet adapter.

Dust Shoe

Our Z-axis independent, magnetic dust shoe allows you to attach standard vacuum hoses to your CNC machine, allowing it to suck up dust as it’s cutting, making clean up easier and keeping dust out of the air. This dust shoe is adjustable in the Z direction, and the front bristles and vacuum hose can be easily detached to make it easy to change bits.

Touch Plate

Our 3-axis touch plate allows you to set the ‘origin’ or starting point of your cutting tool very accurately based off the surface of the material you’re going to be cutting. Place the touch plate onto the corner of the material to locate the cutting bit in both X, Y, and Z-directions to start your cutting job, or use it to set the Z-height of the tool to accomplish tool changes on more complicated projects.

End Mill Starter Set

Our End Mill Starter Set comes with a basic set of end mills to get your started for many projects you might have in mind. Each pack comes with:

LongMill MK2 Dust Shield

Prevent dust and debris from getting into your Y-axis lead screws with our dust shields designed for the LongMill MK2. Each pair of dust shields are made from formed sheet metal which are easily installed between the front and back feet of your machine using M5 hardware. Please note that the ACME lead screws and Delrin Anti-backlash nuts used on the LongMill are designed to work in dusty conditions and the dust covers are not required for general use. Please note that this dust shield only fits the LongMill MK2 30×30.

Inductive Sensors

Inductive sensors allow users to add homing and limit switch functionality to their machines. We only recommend this kit to advanced users


What materials can it cut?

The LongMill is primarily designed for cutting wood but is capable of cutting foam, plastic, and soft metals such as aluminum and brass.

Where can I buy end mills and other tooling?

End mills and bits are available on sale on our website as well as online such as Amazon and Ebay, or at your local hardware store such as Home Depot or Lee Valley.

What software can you use with the LongMill?

The LongMill is compatible with dozens of free and paid CAM software. The LongMill is compatible with standard G-code. You can check out our resources page at www.sienci.com/resources and look under the software tab. We’ll be hosting webinars and creating additional resource videos to help you learn to design and program your CNC machine.

What system requirements are there?

You can run your machine off virtually any modern laptop made in the last 5 years running Windows, Mac OS, and Linux.

We’ve tested our machine with Intel Celeron and AMD Phenom processors with less than 2GB of RAM with no issues (although it is a bit slow).

For any other downloadable CAD or CAM programs that don’t run on the cloud, please check with the software creator for minimum system requirements.

What spindles or routers can I use?

While we recommend the Makita RT0701/RT0700, you can also use other trim/palm style routers. You will be able to let us know what tool you want to use and we will send you the appropriate mount.

Will there be 4th or 5th axis support?

In the immediate future, there will not be 4th or 5th axis support for the LongMill.

If you would like to implement an additional axis to your machine, we encourage users to try creating their own and sharing it with the community!


The LongMill has a 90 day warranty once it arrives at your door.

We want you to have a great experience with your machine, so if any parts are found to be missing or damaged, please email us. We will ensure that you receive the support you need to restore your LongMill to operating condition or provide a full or partial refund.

You may cancel an order if it has not shipped yet, please contact us if you wish to do so. We do not offer returns for LongMills that have already shipped.

General Warranty and Limits of Service:

Effective March 4, 2019

Throughout this policy the words “we”, “us” and “our”, or “Sienci Labs” will be used to refer to Sienci Labs Inc. herein and “LongMill” or “machine” will refer to Sienci Labs’ Sienci LongMill 12×12, Sienci LongMill 12×30 and Sienci LongMill 30×30. Additionally, the words “you”,  “your”, “user”, and “operator”  will refer to the original purchaser/customer, user, or viewer of any of the products or media provided by or through Sienci Labs.

Sienci Labs Inc. (the “Company”) grants the LongMill (the “Product”) a standard warranty within Canada and the US to the original customer to be free from missing parts, defects in material, and defects in workmanship for a period of ninety (90) days from the date of receipt by the original purchaser. Sienci Labs Inc. will ensure that the appropriate support is provided to the original customer to restore the LongMill to operational condition or provide a full or partial refund under the sole discretion of the Company.

This warranty does not cover damage due to improper use or assembly, lack of maintenance, normal wear and tear, or modifications to the LongMill which are not produced or authorized by the Company. Consumables such as cutting tools and sample or stock materials which may have come with your LongMill are not included in this warranty.

This warranty will become void if the operator does not follow the Safety Warnings and Guidelines, uses the Product for illegal purposes, intentionally causes damage to the Product, or transfers the Product to another owner.

The original customer must contact Sienci Labs Inc. within ninety (90) days of receiving their order to make a warranty claim to be eligible for warranty service. Proof of purchase, tracking number, email address, or other material will be used to confirm the original purchasing date and the identity of the original customer. If damage was due to shipping, original packaging materials must be kept in the original received condition. Photos, videos, written descriptions, and other items may be requested to assess and validate a warranty claim.  In the case Sienci Labs Inc. requires the original parts to be returned, the customer is solely responsible for packing all items securely. Damage incurred during return shipping will not be covered by the warranty. A method of payment such as a credit card may be requested by Sienci Labs Inc. to cover shipping costs or damaged items if Products are not eligible for warranty service.

367 reviews for LongMill Benchtop CNC MK2

  1. Richard Jaffe (verified owner)

    I am having a blast. My previous machine was a smaller belt driven machine that gave me a lot of problems. I built this machine with the controller and such on the right hand side as opposed to the left hand side as suggested because I am right handed and it makes it more convenient for me. In short, I love it!!

    (0) (0)
  2. Bradley Soileau (verified owner)

    Love it

    (0) (0)
  3. Mark Freund (verified owner)

    Hello Chris. I have been stuck with the programming. I can move the router with the laptop, zero it out with touch plate. but can’t seem to get the designs loaded into the program. I did get one but it’s backwards . I have also broken 2 bits already. I like the machine but I’m stuck.

    (0) (1)
  4. Michael Schillizzi (verified owner)

    Price is very good for what you get. It adds up quicker when you start ordering other accessories and items that you need, but I would do it all over again.
    The extra items are very needed to complete the tasks that you need and want to do.
    All the items are very helpful to better yourself in your new venture.

    (0) (0)
  5. RANDY C. (verified owner)

    Big improvement over my smaller 3018

    (0) (0)
  6. Dave Vaughan (verified owner)

    Everything is good. My control box started on fire yesterday afternoon. I was going to come to your shop today. Roads are a skating rink right now. Might be tomorrow instead.

    (0) (0)
  7. Michel Matton (verified owner)

    Excellent build docs! Machine runs like a charm after grounding the y rails and x gantry. Dust boot does a great job keeping things tidy. This is my first time building and using a machine like this.

    (0) (0)
  8. Thomas (verified owner)

    The machine itself is great, great hardware, very sturdy.
    Squaring can be difficult, including a jig for the proper distance between legs would be extremely helpful and achieved with a piece of either wood or metal.

    (1) (0)
  9. Ralph Tate (verified owner)

    First let me explain that for years I was a machinist. I then worked as an inspector in the field of military products. After building the MK2 I was surprised how well the design was. The extruded beams are very strong. The configuration of the beams lend support and strength. No burrs were found on any parts. All threads were properly made and I had no problem with any application of the bolts. Your instructions and videos were very helpful with the build. All electronics were well made and easy to attach. Once the machine was squared and tramed, I ran a break in program for 50 passes without any complications. Once that was completed I attached my spoil board and used the gsender program to face the surface. The cut was clean and without any ridges. My only suggestion would be to extend the rail clip on the x axis. The wires ran along the y axis rail chain and could possibly cause a pinch point. I extended mine with a small piece of wood that had two holes drilled into it for tie wraps. Now the wires clear the chain without problem.

    (3) (0)
  10. Brian (verified owner)

    The online reviews are what convinced me to order this unit and I am not disappointed. The setup process is straightforward and the instructional videos are very detailed. I would recommend the MK2 to anyone who wants to build things successfully with confidence.

    (0) (0)
  11. David Lemons (verified owner)

    this thing is junk had it more than six months and haven\’t made one cut that is right.

    (4) (11)
  12. Bill A. (verified owner)

    It’S an awsome machine. gsender is is probably the best software I’ve used. looking forward to using it more when winter is over.

    (0) (0)
  13. Phillip Price (verified owner)

    Other than adjusting the router by shimming the mount it is very good. No problems

    (0) (0)
  14. Antonio Gonzalez (verified owner)

    I’m very happy with the purchase but life got delayed the set up and construction and it is still in the box waiting to be assembled
    Will advise once is put together


    (0) (0)
  15. Jack D. (verified owner)

    Machine is great. Still learning, but made 2 simple projects and one more complex and happy with the performance. Some pre-assembly ( putting small parts together so they could still ship in one box) would be even better. Putting it together was a bear with too many steps.

    (1) (0)
  16. Doug Moore (verified owner)

    Nice solid unit, intuitive to assemble, great online video support. Great interactive community, wrought full of advice and ideas for your table, spoil board and hold-down options.

    (0) (0)
  17. Peter Dunshie (verified owner)

    easy to setup and run

    (0) (0)

Only logged in customers who have purchased this product may leave a review.