Shapeoko Upgrade - Quiet Cut Spindle with TinyG

We have already seen in a previous post how to upgrade your Shapeoko with the Quiet Cut Spindle when using a gShield. Some people may be looking for the next step up from the gShield and Arduino combination. That my friends is the TinyG.

Wiring of TinyG CNC controller to speed controller and quiet cut spindle.

TinyG and the Shapeoko make a great couple. The TinyG is created by Synthetos that brought you the grblShield and the gShield.  Not only do you get all the great aspects of the gShield & Arduino combo such as free software to send the G-code, small and economical form factor and USB connectivity, but you get much more. Without getting into all the details, the main reason why you would want to control your Shapeoko with a TinyG are the following...

• smoother motion control for better looking cuts
• 4 stepper motor drivers (instead of 3 with gShield)
• spindle control built in (on/off and RPM)
• supports limit & homing switches

The TinyG + Shapeoko + Quiet Cut Spindle make it even that much better of a match. Being able to control the spindle on and off with software as well as the RPM gives you that much better control. The spindle is controlled from the TinyG but you still need the speed controller as well to interpret the PWM (Pulse Width Modulation) signals from the TinyG to send the correct RPM to the spindle.

Enough talk about why, lets get doing!

Hooking it up to work with the TinyG on the Shapeoko is a straight forward procedure that only requires a few more items, and most people should be able to perform the upgrade in a few hours.

To make your life a little easier, we've compiled all the parts necessary for this upgrade into a single project that can be purchased here.

The Quiet Cut Spindle has several features that make it perfect for this application.

• very quiet, compared to the rotary tool, you barely hear it running
• great tool holding, with a industry standard ER11-A collet included
• additional collets available
• air cooled
• compact and light weight
• affordable

Additional items:

• 48VDC Power Supply (part# 30353-03)
• power cord
• Speed Controller - for machine control (start/stop only) and adjusting spindle RPM
• 2 conductor 18-14 Ga wire to extend spindle motor wire
• heat shrink tubing or crimp connectors for extending spindle motor wire
• tgFX software, free
• power strip, optional

Tools needed:

• soldering iron & solder
• wire stripper
• wire cutter
• screwdrivers
• multimeter for testing, optional

Video Tutorial:

Illustrated Directions:

Step 1) Extend spindle motor wires
Temporarily mount the Quiet Cut Spindle in the Shapeoko. Measure the 2-conductor wire needed to extend motor wires to where the 48VDC power supply and speed controller will be located. Measure twice, cut once. Extend motor wires by soldering on new wires and covering with heatshrink tubing or by using crimp connectors. Soldering and heat shrink is the preferred method.

Step 2) Wire 48VDC power supply
NOTE: check the input voltage on Power Supply. The default setting is 220V. Use a small screwdriver to slide the switch if needed. Wire a grounded power cord from Inventables. I stripped the wires to expose the ends and connected them to the power supply. They come with one end stripped as well to skip that step. They are color coded. For 110V in the USA green is earth, white is neutral and black is load. You can use a power strip for both power supplies so you can power the gShield and the spindle all at once.

Note power supply switch for input voltage. Make sure to switch to 110v if used in the USA.

Power in from outlet via power cord (shown on right) green is earth (ground), white is neutral, black is load. Please follow local standards in your country if different then the USA. 48VDC wires on left go to speed controller.

Step 3) Wire 48VDC power supply to speed controller
Use some more of the 2-conductor wire hook up the 48VDC output from the power supply to the input side of the speed controller. Note the speed controller can accept both AC and DC power so polarity does not matter on the input side of the speed controller.

Step 5) Wire spindle to speed controller
Wire the spindle directly to the speed controller. Make sure to match the polarity. Red is positive, black is negative.

Step 6) Change jumper on speed controller and remove potentiometer
Because we are using the speed controller with software via PWM we need to change the jumper position to disable the potentiometer and enable PWM. Move the jumper closest to the PWM terminal to do this. Also remove the potentiometer as it will not be needed, but save it if you want to use it later on a different build.

Put jumper on side closest to PWM terminal. Remove potentiometer from speed controller.

Step 6) Wire TinyG to speed controller
Use two wires to connect the PWM controls to the speed controller. The terminal labeled PDM on the TinyG is the positive wire (shown in yellow below). The ground terminal is on the same terminal block.

Use the terminal block on the TinyG as shown above to hook up the PWM wires to the speed controller.

Step 7) Hook up 24VDC power to TinyG
Power the TinyG with 24VDC. Make sure polarity is correct. There is a terminal on the TinyG just for power.

Wire 24VDC to TinyG.

Step 6) Configure TinyG for Shapeoko with PWM spindle control
Having both the 24VDC power supply for the gShield and the 48VDC power supply hooked up to the same power strip is an easy way to power both at once. Power on the system. Plug the TinyG to your computer via USB and launch tgFX.

Connect to TinyG

1. Click the Re-Scan button (upper right) to find what USB port is available
2. Click Connect Button 

Confirm TinyG default settings

1. Click on the Axis tab (upper left)
2. Confirm default settings on Velocity Maximum (circled below in photo), it should read 600

Confirm settings of default TinyG settings. Velocity Maximum(circled above right), it should read 600.

Load ShapeOko settings in TinyG

1. Click on Machine Settings tab (upper left)
2. Highlight Shapeoko config (right column)
3. Click Load button (bottom right)
4. Wait for the settings to load and then power cycle the board (re-boot)

Follow steps above to load Shapeoko setting on TinyG controller. REBOOT after settings are applied.

Confirm TinyG Shapeoko settings

1. Reconnect to TinyG
2. Click on the Axis tab (upper left)
3. Confirm default settings on Velocity Maximum (circled below in photo), it should read 1600

Confirm settings TinyG Shapeoko settings. Velocity Maximum (circled above right), it should read 1600.

Add PWM settings to TinyG

1. Click the Gcode tab (upper left)
2. Enter PWM settings line by line in command line prompt on bottom of screen
3. Confirm settings after each line, they will be echoed above

Here are the PWM settings to apply listed below. Enter them one line at a time and hit return.

$p1frq=5000
$p1csl=0
$p1csh=10000
$p1cpl=0
$p1cph=1
$p1pof=0

Select Gcode tab (upper left) then enter PWM settings line, by line and look for confirmation on screen.

Step 7) Confirm your settings
Secure the spindle securely in the Shapeoko. Also remove the bit if you have one installed and make sure the collet is secure. Put on your eye protection. Type M03 (with a zero not an O) in the command line to turn on the spindle. M05 should stop the spindle. Type S2000 for a slow speed or S8000 for the maximum speed of the spindle.

Type directly in the command line to turn the spindle on and off M03 (on) and M05 (off). Type S2000 for a slow speed or S8000 for the maximum speed of the spindle.

Note: the CAM program you are using is probably putting M3 or M5 in already near the beginning and end of the gcode. If not, it is usually an option somewhere or in the post processor. Also M3 and M03 are usually interpreted the same by the machine controller, so either will work. Same for M5 and M05. Please open up your G-code in a text editor or tgFX and preview before running your job.


Troubleshooting:
If you are not getting the spindle to power up check the following. Do you have a green light on the power supply? If not check the input voltage and wiring. You may need to power it down for 10 seconds or longer for it to reset. Check the lights on TinyG for power and also another LED for Spindle. If you need more help you can send an email to help@inventables.com.

Milling 101: Understanding Milling Bits

Choosing the right milling bit for the job at hand can be an extremely important factor in whether a milling project comes out amazingly, alright, or not at all. Combine that with having more choices of bits than materials, and choosing the right bit can be quite a difficult task. However, by answering a simple set of questions, you can greatly simplify your choice of bit. Here are the things you need to ask:

• What material am I cutting?

• What is my machine capable of?

• What shape am I cutting?

Let’s quickly go through each of these and what they mean.

What material am I cutting?

Your material is one of the most important single factors in choosing a bit. Materials have a lot of properties that matter both for your design and cutting (hardness, density, size) as well as just for cutting (how does it chip? melting point, thermal conductivity). For any combination of these properties, one thing remains constant: your bit must be sharp. A dull bit will always cut poorly, and can actually be dangerous to use due to increased likelihood of breakage. Most of the bits sold by Inventables are made of solid carbide, which is an excellent choice for small machines because of its stiffness, durability, and versatility.

Your material likely breaks down into one of three categories: plastics, woods, and metals.

Plastics are fairly soft and extremely versatile materials. They cut easily and tend to take a very smooth finish with no further processing. Plastics also form very nice chips off of the bit when they are being cut, which makes choosing your cut settings very predictable (but we’ll get to that later).

Wood is beautiful and strong, and although it cuts smoothly and quickly, it doesn't tend to be as smooth as most plastics. This is because wood has grain and fibers, which tend to tear and bend when you cut them, rather than cleanly shear. Wood also forms small chips and dust when cut rather than continuous curls like plastics tend to.

Metals (particularly softer metals like aluminum and brass) are the strongest, hardest, and most difficult to cut of the three groups. You can do amazing things with metals, but only if your machine can handle it. Speaking of your machine, that’s the next thing to think about.

What is my machine capable of?

Cutting any material puts a strain on your machine. For smaller machines like the Shapeoko, this often shows as the spindle twisting side-to-side, or the whole x-axis twisting front-to-back. Whenever your machine moves like that, you lose accuracy and unnecessarily wear your machine down. Cut settings and bit choice can minimize the force needed to cut a material, resulting in less strain on the machine. That being said, a stiffer machine will allow use of larger bits and higher speeds. The other thing to consider is how fast and accurate the spindle of the machine is. In general, for small machines, the higher the speed the spindle can reach, the better. It is also important to have the spindle be accurate, with very little wobble. When a bit is in the spindle, if it is not straight or wobbles (the spindle has runout), the bit will not cut evenly or accurately. Smaller bits can even break if the spindle is inaccurate enough.

What shape am I cutting?

Most jobs fall into two categories of geometry: 2.5D and 3D. 2.5D jobs have two-dimensional shapes that are cut to different depths. 3D jobs have complex, 3D surfaces. 3D machining requires a different bit shape than 2.5D machining. The other important thing with both 2.5D and 3D is what the size of the smallest detail is. In general, you want to choose the largest bit that can both cut your part and be safely used in your machine. A larger bit is stronger, and allows you to remove more material faster. However, larger bits can’t cut smaller corners or details, so you must consider the detail you need when choosing bit size.

So far we’ve been pretty general, so let’s dive into some specifics about the actual cutting bits.

This is a generic, 4-flute, square end mill. It’s one of the most common bits you can get. Let’s go over what that means. There are channels between each cutting edge called flutes. They act to carry away the chips from the cut. In this case, there are four of them, meaning there are also four cutting edges. The flutes spiral up towards the shank of the bit, so we call it an upcut bit. Finally, the edges of the bit all the way at the bottom are square, making it a square end bit. They could also be chamfered (bull end) or rounded (ball end). There are a few measurements on the bit itself that are important. There’s bit diameter (how big around the part that actually cuts is), shank diameter (how big the part that goes into the spindle is), bit length (how deep the bit can cut), and overall length (how long the whole bit is). Additionally, there’s the number of flutes (usually 1, 2, or 4) and the angle of the flutes (although we really only care if it’s up, down, or straight).

Now let’s focus on the cutting action. When the machine is running, the bit is spinning and being pushed into the material. Whenever one of the cutting edges comes into contact with the material, it cuts it away into a chip. The chip curls into the a flute of the bit, and is flung out from the cutting area to contribute to the mess around your machine.This is where the angle of the flutes comes into play. If you use a standard upcut bit, then as the bit cuts, it also pulls slightly up on the material. This is great for pulling chips out of deep, narrow cuts. However, on woods or laminates, that slight upward pull can cause a some chipping of the grain around the top edge of the cut as the grain is pulled upward instead of shaving cleanly off. A straight flute bit pulls material neither up nor down, and so behaves well on wood. Straight flute bits are especially great for plywood, as they reduce chipout on both the top and bottom surfaces. Downcut bits push material slightly downward, which is good for cutting thin laminates as it leaves the top surface very clean. However, chips can build up in the cut, affecting deeper cuts. This is somewhat true of all bits. If chips are not cleared from the cut, then when the bit comes back to the same location, it will be re-cutting those chips as well as the existing material. This shortens the life of the bit, makes cuts less accurate, and can reduce the quality of finish that your bit will leave on the material. Bit shape is one way to clear chips from a cut. Brushes, vacuums, and small blasts of air are also effective.

So with that being said, let’s look at some bits and when to use them.

25295-02

Two-Flute Square-End Mill

This is the workhorse bit. It’ll cut just about anything but the despair around a broken heart.

25295-01

Two-Flute Straight Cut End Mill

It’s awesome for cutting plywood because the flutes don't pull upward as they cut, which reduces chipping in the top layer.

25294-02

Two-Flute Ball End Mill

The end is round, which allows for fine detail to be cut on 3D surfaces. It will not, however, cut flat horizontal surfaces.

25295-03

Single-Flute Upcut End Mill

This is another upcut bit, but it only has one flute and the tip of the cutting edge resembles a hook. It cuts plastics and other really soft materials beautifully, and the hook tip helps cut through thin materials better.

30423-01

Fishtail End Mill

This is a slight variation on the standard square end mill, in that the tips of the cutting edges extend down past the center of the bit. It’s good for punching through thin material and getting fine detail.

26007-01

Engraving Bit

The tip is really tiny, only 0.01” in diameter! It’s tapered to make it stronger, which also has the effect of making the cutting diameter increase the deeper you cut. These bits are only for engraving very fine detail, but they’ll do it in any material.

With that selection of bits, you can mill just about anything that will fit on your CNC router. So make a choice, and go get your mill on!

Shapeoko Upgrade - Quiet Cut Spindle with gShield and Relay

One of the best upgrades for the Shapeoko is to use a spindle instead of the rotary tool that many start with. The 300 Watt Quiet Cut Spindle from Inventables works great with the Shapeoko desktop CNC. It is a great upgrade for many other DIY CNC router designs as well.

To make your life a little easier, we've compiled all the parts necessary for this upgrade into a single project that can be purchased here.

The Quiet Cut Spindle has several features that make it perfect for this application.

• very quiet, compared to the rotary tool, you barely hear it running
• great tool holding, with a industry standard ER11-A collet included
• additional collets available
• air cooled
• compact and light weight
• affordable

Hooking it up to work with the gShield (previously known as grblShield) on the Shapeoko is a pretty simple procedure that only requires a few more items, and most people should be able to perform the upgrade in a few hours. When the gShield is hooked up correctly the spindle will turn on and off with G-code directly with software. To make this happen the Arduino sends a signal as 5VDC though pin D12 to a relay. Although the gShield and Arduino combination can signal the spindle stop and start commands, it would damage them to run the 48 volts for the spindle directly. By using the relay we separate the voltages from the controller and the power supply. Think of the relay like a remote controlled switch. With a more sophisticated controller like the tinyG the relay is not needed and also the speed can be controlled as well with software. A tinyG and Quiet Cut Spindle blog post is in the works.

Additional items:

• 48VDC Power Supply (part# 30353-03)
• power cord
• Speed Controller - for machine control (start/stop only) and adjusting spindle RPM
• Isolated Relay Circuit
• 2 conductor 18-14 Ga wire to extend spindle motor wire
• heat shrink tubing or crimp connectors for extending spindle motor wire
• header pins, optional
• power strip, optional

Parts needed for this upgrade to the Shapeoko

Tools needed:

• soldering iron & solder
• wire stripper
• wire cutter
• screwdrivers
• multimeter for testing, optional

Final wiring for all components in this upgrade.

Video Tutorial:

Illustrated Directions:

Step 1) Extend spindle motor wires
Temporarily mount the Quiet Cut Spindle in the Shapeoko. Measure the 2-conductor wire needed to extend motor wires to where the 48VDC power supply and relay will be located. Measure twice, cut once. Extend motor wires by soldering on new wires and covering with heatshrink tubing or by using crimp connectors. Soldering and heat shrink is the preferred method.

Step 2) Wire relay to gShield
Add three pins to gShield used to connect to the relay circuit. You will need to connect to +5VDC, ground and digital pin D12 on the gShield. For this example I soldered on header pins to the gShield and then used female to female jumper wires, included with the relay. Feel free to use whatever technique you want for your application. In the photos and video I used red for +5VDC, green for ground and Yellow for signal (D12). See photos for wire locations.

gShield removed from Arduio to show where pins are located.

Arduino UNO board with arrows to show where to connect to relay.

I used header pins in this example to hook up wires to relay. I soldered these on to line up with the Arduino pins.

I used a "helping hand" tool to hold the glShield and rested the pins on a roll of tape to hold pins in place while I soldered.

Closeup of gShield with wires attached to relay board.

Wires from gShield to relay. Red is +5VDC, yellow is signal wire from D12, green is ground. Blue wire is unused.

Step 3) Wire 48VDC power supply
NOTE: check the input voltage on Power Supply. The default setting is 220V. Use a small screwdriver to slide the switch if needed. I cut the end off of a grounded power cable from Inventables. I stripped the wires to expose the ends and connected them to the power supply. They are color coded. For 110V in the USA green is earth, white is neutral and black is load. You can use a power strip for both power supplies so you can power the gShield and the spindle all at once.

Note power supply switch for input voltage. Make sure to switch to 110v if used in the USA.

Power in from outlet via power cord (shown on right) green is earth (ground), white is neutral, black is load. Please follow local standards in your country if different then the USA. 48VDC wires on left go to speed controller.

Step 4) Wire 48VDC power supply to speed controller
Use some more of the 2-conductor wire hook up the 48VDC output from the power supply to the input side of the speed controller. Note the speed controller can accept both AC and DC power so polarity does not matter on the input side of the speed controller. Also connect the negative wire from the spindle motor on the negative terminal on the output of the speed controller.

Speed controller has input on right side as shown and output on left side.

Closeup of jumper position on speed controller for use with gShield.

Step 5) Wire relay to speed controller
The relay circuit board has three contacts via a terminal block. We are going to use the NC (normally closed) pair. This means that if the relay is not powered the circuit is closed and power is being sent from the 48VDC power supply to the spindle. Once gShield, via the Arduino, triggers the relay via the D12 pin, the relay will energize and open the circuit making the spindle stop. Please see the photos or video for wire locations.

Wires on left connect to gShield, wires on right are the +48VDC wire from power supply and +48VDC to spindle. It does not matter which wire is connected where as long as they use the two right terminals (Normally Closed).

Step 6) Power up and test
Secure the spindle securely in the Shapeoko. Also remove the bit if you have one installed and make sure the collet is secure. Put on your eye protection. Using the potentiometer connected with the 3-conductor white wire to the speed controller move the dial to the middle position. Having both the 24VDC power supply for the gShield and the 48VDC power supply hooked up to the same power strip is an easy way to power both at once. Power on the system. You might hear the spindle start up momentarily until the grablShield initializes. Plug the gShield to your computer via USB and launch Universal-G-Code-Sender. Once you have connected to the machine you can test your connection by jogging the machine via one of the axis. If that works then type M03 (with a zero not an O) in the command line. to turn on the spindle. M05 should stop the spindle.

Note: the CAM program you are using is probably putting M3 or M5 in already near the beginning and end of the gcode. If not, it is usually an option somewhere or in the post processor. Also M3 and M03 are usually interpreted the same by the machine controller, so either will work. Same for M5 and M05. Please open up your G-code in a text editor or Universal Gcode Sender and preview before running your job.

Type directly in the command line to turn the spindle on and off M03 (on) and M05 (off). You can then add this directly to your G-code. If your spindle does not turn on check the potentiometer on the speed controller.

NOTE: there are no software changes that need to be made to make this work. The M03 and M05 commands are standard G-Code commands and are already included in the libraries.

Troubleshooting:
If you are not getting the spindle to power up check the following. Do you have a green light on the power supply? If not check the input voltage and wiring. You may need to power it down for 10 seconds or longer for it to reset. Check the lights on the relay circuit to see if they are being triggered by the Arduino and gShield. Also check the speed controller potentiometer. Set the dial to the middle position when testing. Once it is working well set it to full power unless you need to slow it down for the material you are cutting. If you need more help you can send an email to help@inventables.com.

Mounting of the Quiet cut spindle:
Due to the smaller size of the spindle you may have to change some mounts on your Shapeoko depending on the size of material you want to cut. We will cover some of these different mounting options in an upcoming blog post.