The LongMill MK2.5 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.
Turn your ideas into a reality with the LongMill Benchtop CNC MK2.5
The LongMill MK2.5 is an improved version of the LongMill MK2, with changes including:
The new SuperLongBoard
Spring Loaded Anti-Backlash Nuts
…and other minor changes.
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 plastics, soft 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. PleaseNote*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
Weight
60 lbs
Dimensions
8 × 10 × 41 in
Size
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.
Add-ons
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.
We recommend using the RT0700/RT0701Makita 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.
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.
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.
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 allow users to add homing and limit switch functionality to their machines. We only recommend this kit to advanced users
FAQ
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!
Warranty
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.
439 reviews for LongMill Benchtop CNC MK2.5
4.8
Based on 439 reviews
5 star
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Rated 5 out of 5
Jeff Small (verified owner)–
Rock solid. I enjoyed taking the time to assemble and fine tune once installed on my newly built CNC table. The CNC has been very reliable and I have had to do very little in terms of maintenance. I couldn’t be happier.
(0)(0)
Rated 5 out of 5
William Bartlow (verified owner)–
This machine is awesome easy to setup and get going, It has changed the way I work greatly increasing my productivity and allowing me to do things I couldn’t easily do before.
(0)(0)
Rated 5 out of 5
Greg Adkins (verified owner)–
Excellent value. I really like this CNC!
(0)(0)
Rated 5 out of 5
Sean Alexander (verified owner)–
Absolutely thrilled to own this.
(0)(0)
Rated 5 out of 5
Glen White (verified owner)–
Been working great but since I updated g sender there are some bugs it will randomly shut off the router
(0)(0)
Rated 5 out of 5
Charles (verified owner)–
Quite pleased with this CNC! I have since upgraded to PWN spindle. The spindle kit was pretty straight forward to install. It is soooo much more quiet!
(0)(0)
Rated 5 out of 5
Matthew D. (verified owner)–
Love using this cnc
(0)(0)
Rated 4 out of 5
Anonymous (verified owner)–
I like my Longmill Mk2 a lot, but I found the final aspects of set-up (leveling and ensuring the two Y-axis rails are correctly oriented) has been the biggest challenge and I feel like I still don’t have it 100%. I also think there should be a mk2 dust shoe that can handle proper dust collector connect 4″ with an equivalent cross-sectional area through the shoe, for proper dust control as dust control is a health issue/concern. Also I find my travel in the X-axis can be a little choppy at medium to higher speeds. All and all for the price and compared to what is out there I love it!!
(0)(0)
Rated 5 out of 5
Paul N. (verified owner)–
I am still learning and a long way to go. Have not had the time commit as I am very busy with my full time job. Took some advise from other owners and really took my time to set it up. Worrked perfect first time.
(0)(0)
Rated 5 out of 5
Mark F. (verified owner)–
Had my machine for almost 2 years and due to a bad surgery I’ve only been able to use it now for the last six weeks. Absolutely loving it. I thought it was gonna be difficult to learn at first, but it really is not.
(0)(0)
Rated 5 out of 5
Bob (verified owner)–
I love my CNC. I am retired and really enjoy the challenge my unit presents as I figure out the programming and finally make it happen in wood. The unit is well built and I am very happy with it.
(0)(0)
Rated 5 out of 5
Gary Parks (verified owner)–
Took my time during assembly, had no problems. Routed electrical cables away from each other and hung my dust collector hose so no static induced issues. My original download of gsender worked from day one so I haven’t updated it. Works flawlessly for me.
(0)(0)
Rated 3 out of 5
STEPHEN COOLBAUGH (verified owner)–
I use V-Carve and g-Sender. On almost every project, the CNC stops running at some point, often it stops multiple times during a project. It disconnects from the port (with error message) or stops with no error message. I have a grounding wire from the vacuum, and the machine is on a surge protector, but neither seem to eliminate the problem. This is extremely frustrating, very time consuming, and very costly.
(0)(0)
Rated 5 out of 5
Ricky P. (verified owner)–
It took longer than I expected to install, but overall the product is good and the machine performs very well.
(0)(0)
Rated 4 out of 5
Russell Kalis (verified owner)–
Unit works as expected.
But let me tell you about my most recent purchase – the Control Panel. I got this unit a little more than a week ago. I have been working with Gilberto if you have any specific questions. The unit would not power on out of the box. How does this happen? Are these units not tested before they are shipped? I expected better.
But another issue I have is that everyone in your organization seems to hide behind email and your electronic correspondence form. It is VERY frustrating when you can’t talk to someone. I encourage you to try it. Do the undercover customer and just try to talk to someone in your organization. It is almost impossible. Maybe you will get a call back from a customer service person that cannot answer your questions. But you will not be able to get a phone number or a call transfer to anyone else. It’s as if the customer service person is trying to shield all of your tech people from calls. I don’t understand it. I am very frustrated. If you want to discuss further, call me at 269-998-8536. I don’t hide behind email.
(0)(0)
Rated 5 out of 5
Michael (verified owner)–
A lot of features for a low price. Works great and love the continuous innovations.
(0)(0)
Rated 5 out of 5
JAMES HAMANN (verified owner)–
Rock solid machine. I haven’t found anything it can’t do so far. Great company to work with and they really foster a good community
(0)(0)
Rated 5 out of 5
John Douben (verified owner)–
The cnc machine longmill 30 X 30 is fantastic after the setup, the dimensions with milling are just right. It was the right choice to buy the longmill. And fast that the machine is, unbelievable. Also the service is top, the machine came in with a dip in the x rail exactly where the wheel runs over, that was a bit of a shock but after contact with cienci labs the x rail was replaced without any problem free of charge. TOP guys !!. I would buy the machine again,
(0)(0)
Rated 5 out of 5
José Sánchez Díez (verified owner)–
Soy carpintero profesional con mucha experiencia y quisiera aprender a trabajar con máquinas cnc para mejorar profesionalmente, esta máquina cumple con todas mis expectativas. Está muy bien hecha, es fuerte y tiene un buen tamaño.
(0)(0)
Rated 5 out of 5
Cameron S. (verified owner)–
Amazing machine. I still have a lot to learn, but the mill itself is just great.
(0)(0)
Rated 5 out of 5
Max (verified owner)–
My experience was mostly rough carpentry, a bit of hobby woodworking, and a lot of 3d printing. Assembly took time but was pretty easy, did it solo only the occasional awkward lift and position.
Customer service is good from what I hear, haven’t had to reach out on anything.
Mostly making gifts for family members. Looking into doing a bit of cornhole customization, seasonal decorations, and I have an idea for workshop organizing that might be of interest to others.
(0)(0)
Rated 3 out of 5
Jeff McLoughlin (verified owner)–
The basic engineering on the Longmill seems reasonably sound for a hobbyist CNC. However, after using it for several months I can honestly reflect that I’ve spent at least 35-40% of my time with the tool trying to head off or debugging hardware issues. Overall, the design seems sound but the delron anti-backlash connectors to the lead screws have been a constant source of binding in the X-axis. This combined with the V-wheel tension that’s maintained with eccentric nuts on the gantry module means you just never really know if you’ve tweaked them just right so the carve will execute properly from the get-go.
The net of this issue is constant uncertainty on whether or not the gantry will maintain its place relative to zero as you set it to work on a carve.
My problem issues primarily involve the x-axis on the 48×30. Today’s job on a $60 slab of walnut that I already had 6+ hours of machine time invested in from the previous day. Because the carve immediately bound up on the x-axis first run and my desire not to flush the job without doing due diligence it required that I spend the first 30 minutes of my day manually running both the x-axis and y-axis front to back and side to side while applying light oil until convinced that the gantry would travel without binding. Prior days to this I’ve applied lithium grease to the lead screws and adjusted the tensions both on the anti-backlash and the v-wheels. I’ve cleaned the rails and been careful about sawdust buildup. It’s just a constant source of anxiety on whether the machine will run as intended on any given job. The stepper motors seem strong enough and the connection between them and the lead screws has been an issue that required excessive force or the set screws to resolve but “I think” I got them cranked sufficiently tight. They occasionally squeal but I cranked the set screws down until the provided Allen wrench snapped off. Like the others issues mentioned above, I’m just never sure everything is addressed with finality. There’s routine maintenance and then there’s constant debugging. Kind of an overall source of mental tension I could do without. No other tool in my shop requires this kind of babysitting to ensure basic functionality.
(2)(0)
Rated 5 out of 5
Stephen Batey (verified owner)–
I bought my first CNC used and started cutting. It didn’t take long for me to know that I wanted a larger, faster and more robust machine. The LongMill MK2.5 filled this bill.
I was very happy with the price and service I received. I built an table for it prior to ordering it, so when my MK2.5 arrived, I was able to start the assembly. I had also watched the assembly videos ahead of time so that process went very well.
I have been making mostly signs and plaques and have started making some games and inlays. I’m very happy with the MK2.5.
(0)(0)
Rated 5 out of 5
Charles Emerick (verified owner)–
So far very pleased, after purchasing a used cnc by another manufacturer and having issues with customer support I have nothing but good things to say about your company and customer support
(1)(0)
Rated 5 out of 5
Janik Hinrichs (verified owner)–
2 slight Problems. The X Axis Motor gets Stuck on full Default throttle (5000mm) i had to set it to 4000mm. And the adjustment screws for the X Rail that hold the Z-Axis need to be adjusted to almost max from the beginning. So later adjustment hardly possible.
Others than that great device! 4,5/5 Stars.
(0)(0)
Only logged in customers who have purchased this product may leave a review.
Jeff Small (verified owner) –
Rock solid. I enjoyed taking the time to assemble and fine tune once installed on my newly built CNC table. The CNC has been very reliable and I have had to do very little in terms of maintenance. I couldn’t be happier.
William Bartlow (verified owner) –
This machine is awesome easy to setup and get going, It has changed the way I work greatly increasing my productivity and allowing me to do things I couldn’t easily do before.
Greg Adkins (verified owner) –
Excellent value. I really like this CNC!
Sean Alexander (verified owner) –
Absolutely thrilled to own this.
Glen White (verified owner) –
Been working great but since I updated g sender there are some bugs it will randomly shut off the router
Charles (verified owner) –
Quite pleased with this CNC! I have since upgraded to PWN spindle. The spindle kit was pretty straight forward to install. It is soooo much more quiet!
Matthew D. (verified owner) –
Love using this cnc
Anonymous (verified owner) –
I like my Longmill Mk2 a lot, but I found the final aspects of set-up (leveling and ensuring the two Y-axis rails are correctly oriented) has been the biggest challenge and I feel like I still don’t have it 100%. I also think there should be a mk2 dust shoe that can handle proper dust collector connect 4″ with an equivalent cross-sectional area through the shoe, for proper dust control as dust control is a health issue/concern. Also I find my travel in the X-axis can be a little choppy at medium to higher speeds. All and all for the price and compared to what is out there I love it!!
Paul N. (verified owner) –
I am still learning and a long way to go. Have not had the time commit as I am very busy with my full time job. Took some advise from other owners and really took my time to set it up. Worrked perfect first time.
Mark F. (verified owner) –
Had my machine for almost 2 years and due to a bad surgery I’ve only been able to use it now for the last six weeks. Absolutely loving it. I thought it was gonna be difficult to learn at first, but it really is not.
Bob (verified owner) –
I love my CNC. I am retired and really enjoy the challenge my unit presents as I figure out the programming and finally make it happen in wood. The unit is well built and I am very happy with it.
Gary Parks (verified owner) –
Took my time during assembly, had no problems. Routed electrical cables away from each other and hung my dust collector hose so no static induced issues. My original download of gsender worked from day one so I haven’t updated it. Works flawlessly for me.
STEPHEN COOLBAUGH (verified owner) –
I use V-Carve and g-Sender. On almost every project, the CNC stops running at some point, often it stops multiple times during a project. It disconnects from the port (with error message) or stops with no error message. I have a grounding wire from the vacuum, and the machine is on a surge protector, but neither seem to eliminate the problem. This is extremely frustrating, very time consuming, and very costly.
Ricky P. (verified owner) –
It took longer than I expected to install, but overall the product is good and the machine performs very well.
Russell Kalis (verified owner) –
Unit works as expected.
But let me tell you about my most recent purchase – the Control Panel. I got this unit a little more than a week ago. I have been working with Gilberto if you have any specific questions. The unit would not power on out of the box. How does this happen? Are these units not tested before they are shipped? I expected better.
But another issue I have is that everyone in your organization seems to hide behind email and your electronic correspondence form. It is VERY frustrating when you can’t talk to someone. I encourage you to try it. Do the undercover customer and just try to talk to someone in your organization. It is almost impossible. Maybe you will get a call back from a customer service person that cannot answer your questions. But you will not be able to get a phone number or a call transfer to anyone else. It’s as if the customer service person is trying to shield all of your tech people from calls. I don’t understand it. I am very frustrated. If you want to discuss further, call me at 269-998-8536. I don’t hide behind email.
Michael (verified owner) –
A lot of features for a low price. Works great and love the continuous innovations.
JAMES HAMANN (verified owner) –
Rock solid machine. I haven’t found anything it can’t do so far. Great company to work with and they really foster a good community
John Douben (verified owner) –
The cnc machine longmill 30 X 30 is fantastic after the setup, the dimensions with milling are just right. It was the right choice to buy the longmill. And fast that the machine is, unbelievable. Also the service is top, the machine came in with a dip in the x rail exactly where the wheel runs over, that was a bit of a shock but after contact with cienci labs the x rail was replaced without any problem free of charge. TOP guys !!. I would buy the machine again,
José Sánchez Díez (verified owner) –
Soy carpintero profesional con mucha experiencia y quisiera aprender a trabajar con máquinas cnc para mejorar profesionalmente, esta máquina cumple con todas mis expectativas. Está muy bien hecha, es fuerte y tiene un buen tamaño.
Cameron S. (verified owner) –
Amazing machine. I still have a lot to learn, but the mill itself is just great.
Max (verified owner) –
My experience was mostly rough carpentry, a bit of hobby woodworking, and a lot of 3d printing. Assembly took time but was pretty easy, did it solo only the occasional awkward lift and position.
Customer service is good from what I hear, haven’t had to reach out on anything.
Mostly making gifts for family members. Looking into doing a bit of cornhole customization, seasonal decorations, and I have an idea for workshop organizing that might be of interest to others.
Jeff McLoughlin (verified owner) –
The basic engineering on the Longmill seems reasonably sound for a hobbyist CNC. However, after using it for several months I can honestly reflect that I’ve spent at least 35-40% of my time with the tool trying to head off or debugging hardware issues. Overall, the design seems sound but the delron anti-backlash connectors to the lead screws have been a constant source of binding in the X-axis. This combined with the V-wheel tension that’s maintained with eccentric nuts on the gantry module means you just never really know if you’ve tweaked them just right so the carve will execute properly from the get-go.
The net of this issue is constant uncertainty on whether or not the gantry will maintain its place relative to zero as you set it to work on a carve.
My problem issues primarily involve the x-axis on the 48×30. Today’s job on a $60 slab of walnut that I already had 6+ hours of machine time invested in from the previous day. Because the carve immediately bound up on the x-axis first run and my desire not to flush the job without doing due diligence it required that I spend the first 30 minutes of my day manually running both the x-axis and y-axis front to back and side to side while applying light oil until convinced that the gantry would travel without binding. Prior days to this I’ve applied lithium grease to the lead screws and adjusted the tensions both on the anti-backlash and the v-wheels. I’ve cleaned the rails and been careful about sawdust buildup. It’s just a constant source of anxiety on whether the machine will run as intended on any given job. The stepper motors seem strong enough and the connection between them and the lead screws has been an issue that required excessive force or the set screws to resolve but “I think” I got them cranked sufficiently tight. They occasionally squeal but I cranked the set screws down until the provided Allen wrench snapped off. Like the others issues mentioned above, I’m just never sure everything is addressed with finality. There’s routine maintenance and then there’s constant debugging. Kind of an overall source of mental tension I could do without. No other tool in my shop requires this kind of babysitting to ensure basic functionality.
Stephen Batey (verified owner) –
I bought my first CNC used and started cutting. It didn’t take long for me to know that I wanted a larger, faster and more robust machine. The LongMill MK2.5 filled this bill.
I was very happy with the price and service I received. I built an table for it prior to ordering it, so when my MK2.5 arrived, I was able to start the assembly. I had also watched the assembly videos ahead of time so that process went very well.
I have been making mostly signs and plaques and have started making some games and inlays. I’m very happy with the MK2.5.
Charles Emerick (verified owner) –
So far very pleased, after purchasing a used cnc by another manufacturer and having issues with customer support I have nothing but good things to say about your company and customer support
Janik Hinrichs (verified owner) –
2 slight Problems. The X Axis Motor gets Stuck on full Default throttle (5000mm) i had to set it to 4000mm. And the adjustment screws for the X Rail that hold the Z-Axis need to be adjusted to almost max from the beginning. So later adjustment hardly possible.
Others than that great device! 4,5/5 Stars.