The AltMill is the pinnacle of hobby CNCing, bringing industrial-level precision to a price point and ecosystem for both beginners and advanced users. The AltMill MK2 2×4 is the perfect CNC machine when time and performance are crucial.
Highlights include:
Production level cutting speeds (approx. 600 inches/minute)
Closed loop motor system on all three axis to auto-correct positioning and auto-stop when necessary (reliable for production style work)
Requires little maintenance during project production
Advanced, production-style features including Y-axis auto-squaring; limit switches by default; and tram adjustment capabilities
Cuts materials ranging from hardwoods to plastics, foams, composites, aluminum – even steel
Support for 80mm spindles and routers
25″ x 49″ working area with a max Z-height of 5.5″
Footprint of 59″ wide and 38″ deep
The AltMill MK2 2×4 comes with a standard 80mm spindle mount only. It does not come with a spindle, which must be purchased separately.
Sturdy metal legs with the ability to add 4ft wide shelving underneath
Welcome package
***Not included with your AltMill MK2 2×4*** Check out our recommended products tabs for an ideal set up, but note the following ARE NOT included with your order:
Computer or laptop
Spindle
End mills or bits
T-tracks
Waste board (e.g. MDF 2ft x 4ft sheet)
Set of metric Allen keys, standard bits or drill for assembly
***Some photos may contain items for illustrative purposes, such as spindles, caster wheels, t-tracks, or additional shelving. There may also be cosmetic differences between the machine in the photo and the production version of the AltMill.
Lead times This product has a potentially long waitlist, relative to demand and seasonality. For more info on expected shipping and delivery times, please see our Order Status page.
Full Payment is required at time of purchase to get your order into the Queue. We ship on a first-come, first-served basis. If you choose local pick-up, you are subjected to the queue order and cannot get your machine quicker.
Power Requirements
We recommend allocating two 15A 110V/120V circuits — one for the spindle and dust collection system, the other for the machine and a computer.
The AltMill consumes 500W and runs off a 48V 10A power supply
The 1.5KW Spindle Kit consumes 1500-1600W at max load
If you live in a country with 220V/240V power you must use a transformer to convert to 110V/120V.
To solely run the machine, you need a rating above 500W
To run the machine and spindle, you need a rating of 2000W
3rd Party Spindles
I would like to source my own spindle, what should I be aware of?
For spindles 2.2KW or above, you will need to install extra 220VAC wiring
The AltMill comes with an 80mm spindle mount, we do not have larger diameter mounts at the moment
The VFDs that may work with our controller are: Huanyang v1, Huanyang P2A, Yalang YL620, H-100, and GS20, however they are not plug-and-play — read this article for further information
More Information
Check out our comprehensive FAQ for prospective customers, addressing questions such as power requirements, spindle sourcing, and bundle deal info.
Warranty
The AltMill has a 120 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 AltMill 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 accept returns for AltMills that have already shipped.
General Warranty and Limits of Service:
Effective March 11, 2024
Throughout this policy the words “we”, “us” and “our”, or “Sienci Labs” will be used to refer to Sienci Labs Inc. herein and “AltMill” or “machine” will refer to Sienci Labs’ Sienci AltMill. 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 AltMill (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 one hundred and twenty (120) 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 AltMill 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 AltMill 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 AltMill 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 one-hundred and twenty (120) 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.
I wish the legs were adjustable. I cut mine off 5″ and welded back to make clearance for other machines in shop. It also allows a sitting position with feet on floor at the machine. Much better for me. This is a great machine for an advanced hobbiest.
(0)(0)
Rated 3 out of 5
Raymond Glover (verified owner)–
I wish I could rate you but I got moved to Washington State for the summer. Check back in 3 months.
(0)(10)
Rated 5 out of 5
Sean Higgins (verified owner)–
The machine goes together easy. Its high quality, ships well. And for a newbie in the CNC realm that’s great for me. There is a lot of information on the machine, but it is spread out over a large number of locations, youtube, the beginner resources for the altmill, and then there is different essential info in the longmill section, and more elsewhere in the instructions. So to be clear, there is no shortage of quality resources, my only suggestion for Sienci Labs would be to cultivate a single location for all necessary information for a single machine in one spot for easy of access and less confusion. Other than that, the machine is incredible, high quality, incredible value for the money and I would 100% suggest it to any friend.
(0)(0)
Rated 5 out of 5
Greg (verified owner)–
Assembly was easily done following the youtube video. Packaging had very clear warnings printed on paper to look INSIDE the X gantry for parts, so that was not an issue for me. Support was very responsive in replacing a noisy motor.
Needs a better dust boot, which I think was mentioned recently (Summer 2025) that it’s under development. It’s annoying changing bits with an ER20 collet, need to move the dust shoe each time.
(1)(0)
Only logged in customers who have purchased this product may leave a review.
AltMill MK2 2x4
1 × $2,790.00 
Donald Ramsey (verified owner) –
I wish the legs were adjustable. I cut mine off 5″ and welded back to make clearance for other machines in shop. It also allows a sitting position with feet on floor at the machine. Much better for me. This is a great machine for an advanced hobbiest.
Raymond Glover (verified owner) –
I wish I could rate you but I got moved to Washington State for the summer. Check back in 3 months.
Sean Higgins (verified owner) –
The machine goes together easy. Its high quality, ships well. And for a newbie in the CNC realm that’s great for me. There is a lot of information on the machine, but it is spread out over a large number of locations, youtube, the beginner resources for the altmill, and then there is different essential info in the longmill section, and more elsewhere in the instructions. So to be clear, there is no shortage of quality resources, my only suggestion for Sienci Labs would be to cultivate a single location for all necessary information for a single machine in one spot for easy of access and less confusion. Other than that, the machine is incredible, high quality, incredible value for the money and I would 100% suggest it to any friend.
Greg (verified owner) –
Assembly was easily done following the youtube video. Packaging had very clear warnings printed on paper to look INSIDE the X gantry for parts, so that was not an issue for me. Support was very responsive in replacing a noisy motor.
Needs a better dust boot, which I think was mentioned recently (Summer 2025) that it’s under development. It’s annoying changing bits with an ER20 collet, need to move the dust shoe each time.