Recently low cost CNC machines have been becoming more popular among creators mainly because they allow us to make virtually anything we want out of virtually any material.

Combined with the right tooling, software such as Fusion 360 or Autodesk Inventor and an imagination, we can now come up with an idea for a product and not only machine it in an afternoon, but we can now batch produce our products in the hundreds or even thousands thanks to machines such as the Tormach PCNC440 or the Shapeoko. 

But what if you just cant afford a Tormach. Maybe you can afford the base model but you want servos, an ATC and fast rapids. Maybe you can afford a Shapeoko or Othermill but you need high precision parts made from stainless steel. Are you planning on converting a G0Z04 to CNC but don’t know how? This machine may be the answer.

There is a lot to read here, but please remember this is a CNC machine so there is a lot to it compared to other kickstarter projects.

 This project will take roughly 45 minutes to read everything

You can zoom out to get an overview

It is called the Samurai-120. 120 refers to the weight of the frame of the machine. 

The Samurai were the warriors of Japan until they were abolished by the industrial revolution and modern machinery in the 19th century. The Samurai stood for perfection. They refined everything they did until they could improve no more, and that happens to represent my attitude towards design & engineering.

CNC stands for Computer numerically controlled and represents the base model.

VMC stands for Vertical machining centre and represents the upgraded version.

It has a 4 tool ATC

It has 14000mm/min Rapids

It has a 1kW Spindle

Its made of 120kg of steel

For £3500

And for the Americans:

It has 551.1811 IPM Rapids

It has a 1.34102 hp Spindle

Its made of 264.555 lbs of solid steel

For $4320.22

Automatic crash detection

Unlike other machines in this price range this machine can actually detect certain crashes and prevent further damage.

Lets say you plunged a drill straight into a part at rapid speed on a standard Tormach machine. Until you press the e-stop, the spindle would keep turning causing damage especially if it has the R8 system which allows for the tool to rotate in the collet and therefore ruining it. Also the stepper motors would stall but they would likely still try and move so if the machine was unattended this would be a recipe for disaster as the machine would not stop itself. 

This could happen to all machines that either use stepper motors or don’t have spindle encoder feedback.

This machine won’t detect things like a part flying out of a vice but in that case, having the machine continue to run poses no danger. Aluminium chip welding detection would only work for tools larger than 8mm (0.3″) diameter. Tool breakage can be detected using the tool height probe.

How it works is really simple:

This machine only uses servo motors. Each servo motor has an alarm function. This alarm is activated when the motor tries to rotate but the built in encoder (rotation sensor) detects that the axle is actually not moving. As soon as this happens the alarm is activated and the e-stop is automatically triggered by the machine which turns off the spindle, stops motion and turns off the coolant.

The axis motors used on the prototype machine have been chosen to provide enough power to take large cuts (kinda) however they are not actually powerful enough to destroy the machine. If you were to crash a large industrial VMC you could potentially be set back thousands of pounds from spindle damage.  The Z axis has a larger motor than the X and Y axis to help with drilling but it also has a larger ballscrew to handle the forces.

All being said, this machine is still very powerful compared to humans and should not be treated as a toy. If used incorrectly it can cause serious injury.

This is what can happen on a big VMC (sound is turned off):

 Or a Tormach:

Here is a video showing an example of what happens on this machine. Note that the spindle is turned off because otherwise it would cause more damage and just drill into the part. Rapids have also been reduced 50%.

 You may notice that it makes two ‘jolts’. The first ‘jolt’ is when it rapids into the part (crashes). The second jolt is the motor being disengaged. There is a delay but it is considerably shorter than your reaction time and if you are not at the machine it will do it automatically. The delay can be made shorter it just requires a bit of configuring.

Almost no damage was caused to the machine (apart from increased wear in the ballscrew) yet the machine can still drill with a 1mm (0.04″) chip load on an 8mm (0.31″) hss drill (not recommended, although it did break the chips up)

This machine can even be used as a lathe, and take a pretty decent sized cut (1mm/0.04″) all things considered.

                 Machining stainless steel on a small machine has never been so relaxing

                                                    Cleaning the machine is easy too

The spindle assembly

The spindle assembly on this machine has some quite unique features that set it apart from other machines.

Firstly the block that moves the spindle away from the column is solid metal, not a tube. Now this block is made from aluminium but since it is basically a solid cube it is very rigid and certainly not the weak point of the machine. 

The first main reason for it being aluminium and not steel is weight. A block of steel that size would be very heavy and would then require an equal counterbalance to stop the spindle from dropping when the machine is turned off. More weight also means slower accelerations.

The second main reason for it not being steel is the thermal conductivity (ability to conduct heat). As you know spindles tend to get quite hot when running at full RPM constantly for hours without cooling and if you are trying to make ‘ultra’ precision parts you may be stuck wondering why your parts are out of tolerance. The aluminium helps to take heat away from the spindle. The flood coolant for the VMC is actually fed through the aluminium block at the top and out the sides so this essentially acts as a spindle coolant too! I measured the thermal expansion at the tip of the cutting tool, parallel to the Y axis and the most I got was (0.008mm / 3.15×10^-4″). The aluminium along with a fan helps to cool the servo motor as well.

The actual spindle itself has 2 bearings. The rear bearing is a 47x25x12 taper roller bearing which takes up the force from the pneumatic cylinder (no, this does not damage the bearings). The main bearing is a 40x80x30.2 double row angular contact monster. 

This bearing can easily handle the cutting forces, and will certainly not be a weak point in the machine. You may have noticed in the pictures that it is not protected on one side. We plan to make a cover for the bearing to prevent coolant and fine chips from getting past the rubber seal.

Machine installation:

Whats impressive about this machine is that it can actually be lifted and carried by 2 people (or one stronger person) and doesn’t require an engine hoist.

This is possible because the machine can be slpit in two halves. 

There is the Z axis column and the base. The Z axis column has the z axis and spindle attached. The base has the X, Y axis and table attached. Together its a large, heavy structure which is fairly difficult to transport and would require a hoist to lift but when detached, it becomes a completely different animal. For transportation the two parts can be placed side by side and are therefore less likely to fall over and also reduce the overall size of the box needed. 

No other CNC machine with the amount of power and rigidity as this one can actually be lifted onto a work surface without the use of a hoist. I myself have found this feature really useful when installing the machine as an engine hoist won’t fit into my workshop. Yes don’t laugh its very small.

To attach the two parts together you lie the Z axis column on its back and position the base up to it so the holes line up. Once all bolts have been tightened to the correct torque you can pivot the machine forward so it is the right way up. The two mating surfaces are precision machined on industrial sized VMC’s to ensure that the machines accuracy is the same every time it is assembled. 

Machine table

You may have noticed by now that this machine does not have a standard T-slot table like you would see on most machines.

When you see CNC setups you will usually see people using a fixture plate of some sorts. Fixture plates are handy because they allow for easy alignment of vices or other fixture plates. They also make it really easy to switch quickly between different fixtures. 

So we made a fixture plate built in to the table. The standard design is M6 with 20mm spacing however since the fixture plate will be machined on the Samurai-120 itself we decided that you can have a custom design. Its also cheaper than using a standard table as unfortunately it is made from mild steel. A hardened table upgrade will most likely be available in the future. Grub screws may be provided to prevent chips and coolant getting into the unused holes.

As standard all tables will be manufactured blank and then if you want you can have a completely custom design or go with the standard options. All that is required is that you send the CAD file for your design or if you don’t want to pay extra, when the machine arrives, you can do it yourself. 

The Automatic Tool changer

So far you have not seen an ATC unit for this machine and that’s because there isn’t one. To keep costs as low as possible I have decided that a tool rack style changer is the best option. It is not as good as a carousel or magazine stlye ATC but because it is so simple it now means that the base model will include one. Compare this to a Tormach where the ATC would cost an extra $4000.

 To change tools manually you hold the tool you want to insert in one hand and grab the tool currently in the machine with the other. Press the foot pedal to release the tool and immediately insert the new one. This method is much faster than having a button on the spindle. With some practice changing tools manually can be done in about 2 seconds.

To prevent coolant and chips landing on the tool holder’s taper, a sliding screen will be placed on the open side. Currently the spindle does not support an air blow function but this will be considered for the final version. This tool changer will use up approximately 50mm (2″) of X travel so if all the travel is needed then the ATC will have to be removed.

This machine is Open source

This machine uses an Ethernet Smooth Stepper to control the motion of the axis and other functions. It uses JMC IHSV57 servo motors on all axis and a generic Chinese AC servo for the spindle. All components and software on this machine are third party and no special components have been created for this machine. Even most of the hardware such as the linear rails, spindle belt, BT30 petal clamp, belleville washers, e.c.t can be found in stores such as eBay or Alibaba. This means that replacement parts (should you need them) can be purchased anywhere online and you will be able to find the best prices. 

Gone are the days where the only place you can find replacement parts is on the suppliers website so they can charge you extra. 

Note: this does not mean that you should change any of the hardware used as it is more likely to hinder performance than improve it. The weak point of the machine is the frame in case you were wondering.

And yes, you could just buy all the components in this machine for about £1800 and build it yourself but you would have to design everything and then pay to get all the parts CNC Machined which would end up costing more and it would take you years to complete and cause a lot of headaches as shown in the main video.  You should always value your time over money.

This machine is basically a DIY CNC that has already been designed, tested, manufactured, assembled and calibrated for you.

Technical details

The Samurai-120 CNC Standard features:

• Automatic homing
• Automatic tool height probe
• Automatic crash detection
• Ethernet smooth stepper control
• Mach 4 hobby licence
• Tool rack style 4 position ATC (this will use up some X travel)
• BT30 5000RPM Spindle
• Rigid tapping
• Accordian stlye way covers reinforced with stainless steel shield
• Fixture plate stlye table
• 280x200x230mm travel (X Y Z)
• 11×7.9x9inch travel (X Y Z)
• Machine mounted Electronics enclosure
• Basic physical control panel (E-stop, pause, start)
• Grease lubrication
• 3D printer tool / laser engraving upgrade ready
• Linear rails on all axis
• Rolled ballscrews on all axis with double row angular contact bearings

Note: Due to the current pandemic which may cause setbacks, features such as rigid tapping and stainless way cover shields may not be developed since they are not critical for the machines’ function.

Technical Specs:

Note these are not final specifications but estimates based on the prototype machine

Requirements to get cutting:

Since this machine does not come with an enclosure or stand some thought will need to go into how you will setup this machine to work best for your space. The machine needs to rest on a flat and level surface which won’t sag over time. You will need a place to put your computer where chips won’t fly on the keyboard and ruin it. You should think about where the air compressor will go and where the nearest power socket is. The e-stop must be mounted in a suitable place for easy access. We would actually recommend building a diy enclosure for this machine as it will keep the chips from going everywhere and will be a lot safer. If this kickstarter is successful, help will be provided for this.

• You will need a computer running windows
• Mach 4 will need to be setup
• Single phase mains power
• Compressed air
• Machine will need to be placed on a flat and level surface
• Thought must go into where to mount the e-stop
• Machine will need to be assembled (attach two halves together)
• BT30 tool holder
• Cutting tools
• Material
• Vice, fixture, or clamps

Whats included:

You should receive the machine without a base or enclosure. The necessary cables and assembly tools will be included. Instructions will be provided by a form of video.

The machine may show some signs of use as it will be tested by manufacturing one part. The part will be a BT30 vice holder which will allow you to change the end mill in the BT30 tool holder. 

First part kit

The first part kit for this machine will include the following:

• Precision Vice
• BT30 tool holder
• ER collets
• End mills
• Aluminium billet
• G code to run the part

Samurai-120 VMC features everything in the standalone machine and:

• Full enclosure
• Machine stand
• Flood coolant
• Chip management system
• Enclosure lighting
• Chip coolant filtration system
• Built in computer
• Built in CCTV to monitor the machine remotely
• 7″ Touchscreen (built into the right front panel of the machine)
• Mini keyboard
• Control panel (built into the right front panel of the machine)

Technical specs:

Note these are not final specifications but estimates based on the prototype machine

Requirements to get making parts:

• Single phase mains power
• Compressed air
• Cutting tools
• Materials
• Vice, fixture or table clamp
• Sheet metal will need to be assembled (fully assembled version may be available but with higher shipping costs)

Whats included

You should receive the machine complete with a base and enclosure. Most of the machine will be assembled but some assembly will be required. The necessary cables and assembly tools will be included. Instructions will be provided by a form of video.

The machine may show some signs of use as it will be tested by manufacturing one part. The part will be a BT30 vice holder which will allow you to change the end mill in the BT30 tool holder. 

First part kit

The first part kit for this machine will include the following:

• Precision Vice
• BT30 tool holders
• ER collets
• End mills
• Aluminium billet
• Small air compressor
• G code to run the part

Machine software

The software that this machine will use is mach 4 hobby. This is the best solution because it has a lot of features and support while being very low cost compared to other systems. 

Mach 4 was completely redesigned and is very different to mach 3. It runs much faster and can handle much larger g-code files. Mach 4 has been running on industrial equipment for years and is still doing so today.

Mach 4 also allows for user customisation. If you don’t like the look or where some of the buttons are placed, then you can change it.

Mach 4 computer requirements:

• 32 or 64-bit Laptop or Desktop
• Windows 10, Windows 8, Windows 7, Windows XP*
• 2Ghz CPU
• 1GB RAM
• Video Card with 256MB RAM(Large G-code files, especially 3D files will require a video card with 512MB RAM or higher) 

 *Windows XP users should use version 4.2.0.4162

Real talk:

Despite all the hype, please remember that this is still a really small machine using low cost components and although it can take big cuts for its size, it doesn’t have much rigidity when compared to a machine such as a Syil x7 or Tormach 770. In the Y direction it is very rigid and will compete with those machines but when cutting parallel to X it is much less rigid. We will be trying our best to optimise the design to have a more similar amount of deflection in all directions. That process may involve reducing the Y travel to 180mm. Also if this machine is used in all day production, we would not recommend pushing the machine to the max. And remember, if the machine doesn’t sound right, then it isn’t cutting right.

Future upgrades

Both machines will be designed with upgrades in mind.

We will try our best to make the switch from the Samurai-120 CNC to the VMC as easy as possible.

We will also be working on a five axis attachment for the mill and a potential lathe attachment to turn the 3 axis machine into a Mill turn .

Unlike other machines of similar size, this one has a BT30 tooling system. This means that the spindle will accept any tool which has a BT30 taper. And that means this machine could be turned into a 3D printer, laser engraver, soldering station, part placer, or really anything you or we can come up with. Although these features will not be included in this version, the machine will be designed with connectors in the spindle head that would allow such attachments to work without modifying the machine.

If it all goes to sh**

Now there is a small chance that everything just doesn’t work out as expected. Things such as a second wave of COVID-19 could happen, or I could become ill or injured. Its hard to predict if something like that would happen but in cases like those I would hope that every one of my backers would be completely supportive and together we would think of a solution. 

If I have just made a miscalculation, and run out of money there are a few things I can do:

• Firstly, ask for enough money to let this project continue
• Include less features in the final product such as the ATC or tool probe, or sheet metal parts but still ship most of the machine
• Ship the machine as a kit so you will have to assemble it
• Have the parts manufactured in china instead of locally

If it all goes to sh** then unfortunately there is not much I can do in regards to issuing refunds. The detailed CAD models of the machine could be provided and a list of components and assembly instructions could be made so whatever stage the machine is at, you could finish it. Having no money and a product that isn’t finished is the worst position to be in so we will not let that happen.

Important notes:

Kickstarter is a crowdfunding platform and not a store.

Some of the details above may change slightly, before the machines are dispatched.

I will be in communication with anyone that backs this project (mostly through samurai_machine_tools on Instagram) so you will be very much aware of any changes that are made and may be eligible for a refund depending on what reward you choose or what change is made. E.g if the machine cannot be shipped with a tool probe then you will not be eligible for a refund. If the machine has to be shipped without a spindle then you may be eligible for a partial or full refund.

If you back this project and have an idea for something that would improve it then send a message and we will have a look to see if it is something worth doing. 

I would like for every backer to feel very much involved in the process so on Instagram I will be posting daily updates of all work being done and will be responding to all your messages with complete honesty.

Throughout this I have used the term ‘us’ or ‘we’ and I am working with a few people, but I, the company owner, will be the driving force behind this project. If I could have the opportunity to work with manufacturers to get this product made and shipped and to then get great feedback from you that would incredible. Maybe this project won’t acquire enough funding, in which case I will simply try again in the future with a different idea or different marketing strategy. But for now I am ready for the hustle to begin