FOUR BELTS AND A PORTABLE SLED TURN A FULL SHEET OF PLYWOOD INTO A CNC BED
Four tensioned belts replace the gantry so a full-sheet CNC can pack away when you are done.
by MaslowCNC
Workshop
Built withESP32
- difficulty
- ●●●●○
- time
- a long weekend
- license
- GPL-3.0
- repo
- repo ACTIVE105 stars
●●●●○ · a long weekend · GPL-3.0 · 105 stars · repo ACTIVE
WHAT YOU’LL NEED
Jump to section
COMPAREE VERDICT
Maslow 4 is an open-source CNC router that pulls itself around on four belts instead of riding a rigid gantry, so it can cut a full 4 by 8 foot sheet yet the core robot stays very portable. The project is honest about the trade: it is much cheaper than a gantry CNC and generally less accurate than a good one. People have cut saunas, tables, signs and a thirty-foot catamaran with it, so the capability is there if you can live with looser tolerances. The control software is a local website hosted on the ESP32 board inside the machine, reachable over USB-C, Wi-Fi direct or your home network from a phone or laptop, and built on FluidNC. The thing most likely to go wrong is underestimating the frame: the sled is portable but you still need a stiff external frame or solid anchors for every cut, and the README says troubleshooting is part of the process. If you want plug-and-play precision or have nowhere to anchor a four-by-eight frame, this is not the project. If you have the space, the patience and a pile of plywood, it is a serious tool.
IN THE REPO
GOOD TO KNOW
- —The build files for all parts live in a separate repository (MaslowCNC/Maslow4).
- —BOM is in the wiki, not a single exported CSV.
- —Firmware is GPL-3.0 and built on FluidNC; no commercial restriction.
- —The README explicitly states it is generally less accurate than a good gantry CNC and not plug-and-play.
- —You still need a stiff external frame or anchors around the sheet — the sled is portable, the cutting area is not.
- —An official kit is sold through maslowcnc.com; you can also print the parts and source the electronics yourself.
Parts to buy
2 itemsFrom our check of the build. Exact quantities and part numbers are in the creator’s BOM.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Videos
The official one-minute Maslow CNC intro video (May 2026). Assembly instructions are on maslowcnc.com and in the wiki.
More builds like this
All projectsGallery
Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Read the README end to end (It lists what is not plug-and-play and where you will spend time troubleshooting)
- 2.Check the mechanics repository for STEP files(Separate repo holds all the CAD; link is in the main README)
- 3.Review the BOM in the wiki(Not a single CSV; parts are listed across multiple wiki pages)
- 4.Decide on your frame(Stiff external frame or solid anchors are required; the sled alone is not enough)
Resources
Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.
KNOWN ISSUES
- Underestimating the frame: the sled is portable but you still need a rigid external structure for every cut, and building or anchoring that structure is not covered in detail.
- Expecting gantry-level accuracy: the README explicitly says Maslow is generally less accurate than a good gantry CNC, so if your project needs tight tolerances this is the wrong tool.
- Choosing the DIY route over the kit: the official kit comes with injection-moulded parts and the custom PCB; if you print and source everything yourself, expect weaker parts and more troubleshooting.
- Skipping calibration: the machine measures position by belt length, so calibration and tuning are not optional and the README warns troubleshooting is part of the process.
- Missing the build files: the CAD lives in a separate repository, MaslowCNC/Maslow4, not in the Maslow_4 firmware repo.
- Planning a build with no space for a four-by-eight frame: if you cannot anchor or build a frame that size, the portability of the sled does not help you.
How accurate is it compared to a gantry CNC?
The README states it is generally less accurate than a good gantry machine. People have cut furniture and boats with it, but if you need tight tolerances for joinery or precision parts, a gantry CNC is the better choice.
Do I need a permanent table?
No permanent table, but you do need a stiff external frame or solid anchors around the sheet for every cut. The sled is portable; the cutting area is not.
Is there a kit I can buy?
Yes. The official Maslow 4.1 kit (custom PCB, motors, wiring, hardware and injection-moulded parts) is sold through maslowcnc.com. You can still 3D print the parts and source the rest yourself if you prefer.
What size sheet can it cut?
A full 4x8 foot (1200 x 2400 mm) sheet, cutting up to 60 mm deep.
Can I use it without Wi-Fi?
Yes. The control software is hosted on the ESP32 board and reachable over USB-C, Wi-Fi direct, or your local network. All three work.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
The README says it is less accurate than a gantry CNC but people have still cut a thirty-foot catamaran with it. What would you trust it to cut, and where would you draw the line?
MaslowCNC
Maslow is developed by Barbour Smith and a community of volunteers. He has iterated on it for more than a decade, from the original two-chain wall-mounted machine to Maslow 4's four belts and portable sled, funded through Kickstarter campaigns that paid for injection-moulded parts and a custom PCB. Builders have cut saunas, tables, signs and a 30-foot catamaran with it.
Keep building — related projects
Same category or platform, picked by how close they are to this build.
NO CAD FILESA man in his workshop recreated the heat shield material that cracked on NASA's Orion - and reproduced the failure
ScienceFor expert builders
FULL CADDIY Direct Drive Steering Wheel — Johannes Lodahl (GitHub)
WorkshopFor advanced builders
FULL CADYou can build a box that makes an old metal lathe cut any screw thread
WorkshopFor advanced builders
NO CAD FILESYou can build a reader that tells you why a dead power tool battery is not actually dead
WorkshopFor intermediate builders
NO CAD FILESThis is an ordinary NES controller and it is running DOOM by itself
WorkshopFor intermediate builders
FULL CADYou can build the 15,000-dollar motor test rig for 370 dollars
WorkshopFor advanced builders
DISCLAIMER
- Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
- Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
- Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
CompareeTEAM2mo agoedited
Practical notes from our verification: the honesty in the README, which says Maslow is less accurate than a good gantry machine and still needs some troubleshooting, is why the project has credibility. The build files live in a separate repository, MaslowCNC/Maslow4, while this one holds the documentation, wiki and the FluidNC-based firmware. The frame requirement is real: the README says the sled needs a stiff frame or external anchors, and it works best on sheets up to 4x8 feet. You do not have to source everything yourself: maslowcnc.com sells a kit with the custom PCB, motors, wiring, hardware and injection-moulded parts; you still supply the router and the frame. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.