home built cnc

What CNC Router Kit Is Best For Woodworking

What Is The Best CNC Router Kit?

Let me tell you now that I have personally built my very own cnc mill. Yet I did not do it with a prepackaged cnc router kit. Allow me to explain why.

The cnc router kits you find commercially packaged all have issues. There is no all in one solution that gives you the most for your money.

Warning: Not everyone can do this. Everyone may want this, but this is serious business. Do not continue down the path of building a full cnc mill unless you are confident in your abilities.

If you wish to see a logical argument for building your own as compared to buying a package… read my article on the ultimate wood cutting machine.

If you wish to see the strengths and weaknesses to cnc milling for woodworking then read “The Truth About Cnc Wood Carving” This will help you decide if it is an investment worth your time and money.

Having said that… Let me break down the best way to begin building your own cnc router kit.

Step 1: Select A Cnc Table With A Rail System

When I say to select a cnc table with a rail system, there are many different options. No matter which you select, you DO NOT want a belt driven system.

Why do you not want belts? A belt will stretch over time. Not only this, but temperature fluctuation can impact the belt as well while you are running.

A rail is made of steel which is driven by a lead screw that is attached to a motor. There is nothing which allows for error in that kind of system. It simply is the best way to go.

Belts require constant maintenance and calibration. That is the old way. The goal is to isolate any potential room for error within the design in order to maintain optimal accuracy.

The more room you give the machine to find error by its design, it will appear in error of the cut. Do not take shortcuts just because of price here.

Step 2: Build The Router Kit’s Electronics Package Yourself

This step may seem a bit daunting, but it is worth it. The weakest link of any cnc router kit package is normally the electronics.

If you do not follow my advice on this step, eventually you will. The difference is you spend twice instead of once.

Among the issues that you run into with the cnc router packages is the wrong wiring, as in by size and not being shielded. Add to this you often end up with the wrong size motors and they are cheap.

Then there are the drivers that simply are sub par.

Each of these components are places which you need the better parts that you can afford. I will soon give a flow of how to help determine what you need.

Know your best cnc wiring practices and use them!!!!

It is best to hand pick the shielded wire and other wiring that you need. This part is easy. If you do not know what you are dealing with here then you need to educate yourself before you go any further in your build.

The motors need to be slightly over powered, not underpowered. This will help in the long run with keeping heat down while they are running prolonging the lifespan.

You will be most likely looking for stepper motors.

The Driver is what commands the motor.

NOTE this please. To begin building your package the flow will work like this: Table Size > Motor / driver size > Power supply > wiring needs

What that means is the size of your table will dictate how much motor power you need. Pushing a gantry means pushing and pulling weight.

Thus the need for that flow. The table size will dictate motor and driver size, which will dictate power needs, and thus wiring needs.

Pay attention to the amp rating of the motors. You will be driving at least 3 from one source. If they are rated at 5 amp then that is 15 amps pulling from what should be an independent breaker.

Keep in mind that all of this must run on what is most likely residential power. To make it more complex for many, it may be a split off in power from their house.

If this is your situation then you will either build a smaller machine, or before it is over you will need a new main power supply.

Step 3: Where A Purchased Cnc Router Kit Will Fail – Your Cnc Controller

If you purchase a cnc router kit I promise you that it will either not have a cnc controller, or it will be a piece of garbage. You need to decide what will drive your machine.

I am not going to blow smoke or pretend to be smart here. When I built my cnc mill I did it with a Linux built controller via Linux Cnc.

Understand I have no personal experience with other “good” controllers, but I have seen bad ones. To put this bluntly, Linux just works. It will run your machine and the job without asking questions, period.

The most difficult part of setting up a Linux controller is the programming. There are forums to help you with this and detailed instructions. Yet believe me it will require a lot of homework and patience.

You are not going to do this overnight. In fact it could take a few weeks. So why go through all the trouble? Allow me to explain.

The crappy slap and go controllers that you can find out there are not only bad, but can cause serious problems. A bad controller can allow for equipment to fry or aid in starting a fire.

The benefit of building with something like what I did in Linux is about more than safety. I can run any kind of Gcode I wish through my machine. I am not limited to a specific architecture.

In the end you gain the best safety that us mere mortals can afford while obtaining the ultimate flexibility. Yet you do have to go through the headaches of coding the thing to get there.

Step 4: Select Toroidal And Other Power Supplies

Your cnc router kit will need to run off of DC power. Sorry but you cannot just plug it into the wall. Here is another place where commercially packaged “kits” fail.

Get a decent toroidal power supply. What brand is decent? Seeing as most of these parts come from China and the companies change a lot, all I can honestly say is to research reviews.

I do remember that I purchased my toroidal supply from Automation Technologies Inc. How they compare to what is out there today you must decide.

If you go the Linux Cnc route, you will also need an alternate 5 to 24 volt power supply. Which of these you may need can depend alternate parts you may wish to supply power to.

The Linux Mesa board, or “brain”, is divided into two parts. One side is for communicating with the computer or “controller”. The other side communicates with the toroidal power going to the motors.

This is done through each of the individual motors driver. The driver sends a pulse like signal similar to Morse code that is interpreted for moving the machine.

Due to this architecture, two power supplies are needed. One powers the board, the other powers the motor drivers and is controlled by the board.

Step 5: Select The VFD Of Your Choice For Your Cnc Router Kit

A VFD powers your spindle (VERIFY the information in that link to your needs, VFD, and spindle! Link is given for general information and reference in understanding).

So lets talk about this for a moment. Get a spindle. Lave the router alone. Just put the router back on the table and be thankful you did this.

A spindle is made to do this job. Routers are not. Get a power supply for the VFD, hook the spindle to the VFD. After this the VFD is wired to the board where the computer can control speeds and feeds on the fly.

Warning! Be very careful who’s advice you follow on how to set up your VFD. I smoked one VFD and spindle due to an idiot. But I was the idiot who followed the advice.

There is no detailed guide for many of these things. The right answers I found came from Linux Cnc forums.

Use the forums. People there have forgotten more than we will ever know or be able to research. Document all you do for future reference.

Step 6: Selecting The Cnc Spindle For Your Kit

Spindle selection is not too complicated. It needs to be water cooled and within your price range. It will long outlast the router idea you had.

If you wish to see a detailed argument for choosing a spindle over a router my linked article will give you this.

Almost all spindles us mortals can afford will come from China. There are some which come from Europe but you will pay serious money for these. The one I have from China is still running years later with no issues.

Do not worry, the same bits for cnc spindles can be used in routers. Many quality brands allow them to be interchangeable. Spindles actually allow for greater ease is using different sizes on the fly in tool changes.

Why Go Through This Trouble Building Your Cnc Router Kit?

Three major reasons exist that should compel you to build your cnc router kit rather than buying a complete package. The first reason is you avoid the shortcuts other people take.

If you paid attention to the above flow in determining motor size and power needs, you should realize the electronics NEED to be customized anyway. There really is no one size fits all kit and this is the second reason.

This is like links in a chain. The link you select will determine the next link. So by building your cnc router kit you can get the power you need and it not break down.

The third reason is that now you can repair your machine when something breaks. Knock on wood… it has been near half a decade for my machine and no repairs have yet been needed. Yes I run my mill quite often.

Build it right the first time.

Tips For Building Your Cnc Router Kit

The “table” or “bed” you select for your machine is actually quite important. Earlier I mentioned needing a rail system being driven by a lead screw. This will automatically knock out many options on the market.

Due to this you could end up like me. The option I selected was a benchtop, although a very large benchtop. I had to build a reinforced table for it to sit on.

A funny side note on this. A family member was worried about a potential thief being able to steal such an expensive piece of equipment. It was built in the room, and it will not fit out a window or a door.

The machine would need to be taken apart to move it. If the thief did try, stored power within the toroidal capacitors would likely stop their heart from beating when they touched the wrong thing.

I say all that to point out this. You need to be safe when building this thing!!! You are pushing some power with larger builds.

Many of the “stands” you see for cnc mills are inadequate for larger machines. There simply is too much vibration. The table I built for it was done with nothing more than 2×4’s and plywood.

After I reinforced it, I could probably prop a car up on it. Yet consider that due to vibration it does need to be a very sturdy surface. It must be able to absorb that constant vibration and movement.

Hire a qualified electrician to do things the right way on the main power supply. You wire the machine parts for electricians do not build Cnc mills running on DC power. Typically engineers do this part.

Dedicate a power sub panel to your table. This can act as an emergency kill switch. It also can act as a buffer to protect your equipment.

During hours the cnc mill is not running that sub panel is off. If a thunderstorm comes by, no big deal. If I am running other equipment that could cause a power spike, its no problem.

It is definitely worth having the power sub panel for being able to break down the power for the different parts. VFD, the toroidal for motors, the main power for the board, the computer, and the water pump for the spindle all need power.

I ran 100 amps to the sub panel. From there I break down that 100 amps into 20 amp blocks by breaker. This way if there is a power surge, or something goes wrong in the mill, the breakdown is isolated.

100 amps is overkill I know. In reality I pull between 35 to 45 amps while running the Cnc full tilt. The breakdown of supply is about safety and isolation when running.

If the Cnc is not running then there is no power flowing. If it is running then I am there by the machine 100% of the time.

Having said all of this still BE CAREFUL! Under the hood of the machine capacitors still store power to interconnected parts! Thus the story about the thief… It will require a defibrillator if you do something stupid.

Indeed pulling 100 amps to the table means that while running you are handicap in other places of your shop. Yet if you are like me and it is a one man shop, then it is no big deal as I babysit the machine anyway.

I will admit I do have a dedicated main power line going to my shop that is separate from my house as well. This is a major advantage I pay a premium for. It is worth the premium for safety via the power company and electricians on big machines.

Building With Cnc Router Kits Is No Game, Take It Serious

As you can see from reading this is no game. Depending on the size of the machine you are wanting to build you immediately begin with limitations by simply having a residential power supply.

From this all else must fit under that umbrella realistically to the needs you have. Fortunately you do not need an engineering degree to accomplish this. Yet taking your time is a must and having common sense will get the job done.

If you are wanting this now or yesterday, then it is not for you. There are a lot of people out there who should not attempt these builds. Be honest with your capabilities.

Impatience will cost you a lot of money and potentially worse with damage or injury. You need to take this serious and do your homework.

I will also advise that you spend a lot of time in different cnc forums reading. You can learn a lot about what does work, and what does not. There simply is too much information to place into a single article.

My above highlights will get you started on the right path of research. Plan it out on paper, then begin acquiring parts to build your cnc router kit, preferably with a spindle rather than a router.

How Long Did It Take Me To Build My Cnc?

I planned the design that I used for about three months. That is three months of research before I ever bought the first part.

I diagrammed the project down to the wires that would connect parts. This was to ensure that I was getting the right parts which I needed.

I purchased the parts at different times. First the cnc bed or framework. It took me a couple weeks to assemble this properly, square, and have my supporting table built.

I then purchased the electronics package and ran the power for the sub panel. Once the wiring was completed I then began to work on the controller and “brain” Linux board for the system.

It took me near 6 months of building before I could ever apply power to the machine. So this does take time and dedication. If you have qualified help I am sure it can be done faster.

I did this having never touched or seen a cnc mill in person before. So… having said that it is possible for you to do. Yet know up front that I had some experience in simple programming. That did help understanding the software.

If you can handle basic fundamentals like php, then the coding aspect shouldn’t throw you for too bad of a loop.