Surfacing the Wasteboard on Your Longmill

Want to learn to surface your wasteboard?

  1. Surfacing your wasteboard helps level the surface in relation to your machine. This means that if you have bumps or uneven surfaces on your wasteboard, or if your wasteboard is higher on one side that the other, surfacing will even out and flatten the board.
  2. Cleans off old marks and scars, leaving you with a new, clean surface to glue, clamp, and mount your workpiece.

Check out our newest video that covers how on Youtube:

For more info and surfacing code for all LongMills, visit our resources page:

Check out these new instructables on modding your Mill One

Troy, a.k.a tmbarbour has put out some really cool instructables on adding some new functionality to the Mill One! You might know him from his Add Homing Switches to a Sienci Mill One CNC project, and he’s made some other cool changes to his machine.

Easy Z Axis Probe for Your CNC Router

This instructable walks you through adding a Z axis probe to the Mill One using the built in pins on the CNC V3 Shield. This makes it a lot easier to automate the process of finding the Z height of your workpiece.

Add an Arduino-Based Optical Tachometer to a CNC Router

Knowing the RPM of your spindle can help you get more consistent results out of your Mill One. Not only that, it’s a cool little add on that’s fairly inexpensive and fun to make. Troy’s instructable covers everything you need to know to make your own.

Sienci Mill One Air/Oil Mist Coolant System

There’s been talks and photos of different coolant systems on the Sienci Mill One Group over the last few months, but this is the first full guide I’ve seen on setting it up on a Mill One. Check it out here:

So why a coolant system? Well, when it comes to cutting aluminum, one of the biggest challenges is to keep the end mill from clogging with aluminum chips that weld themselves due to the heat created by friction. Aluminum has a fairly low melting point, making it a material susceptible to this.

There are a few methods to make sure you don’t damage your end mills. One is to make sure that the chips you’re creating are large enough to carry the heat created away from the cut. This is where using a single flute aluminum bit works well, since the single, large flute creates larger chips than what a 2 flute or a 4 flute would typically do. This works great with most jobs, and typically you won’t reach those temperatures. However, with long jobs that can take several hours, some sort of cooling is nice to have.

Andrey’s method of using a mist coolant system is commonly used in industry on large, industrial machines. It uses a blast of air, mixed with a stream of vaporized coolant, pointed toward the end mill to lubricate and cool the part and the tool. Unlike flood cooling, which uses a stream of liquid coolant that sprays at the tool, mist cooling requires far less coolant, and if properly set up, a lot less messy.

If you’ve had this mod in mind for your Mill One, check it out!



Turning the Mill One into a 3D printer


3D printers technically ARE CNC machines because they use “Computer Numeric Control” systems, but when it comes to CNC routers we start to see some major differences between the two types of machines.

Almost all consumer facing 3D printers are FDM (Fused Deposition Modelling) 3D printers, laying down layer by layer of molten plastic to create 3D objects. They use a variety of mechanical systems to move a nozzle which extrudes out the molten plastic to build up that object.

CNC routers work in a similar way, except starting with a block of material and removing material using a rotating cutting bit until you’re left with a object.

Before we dive into how the Mill One was converted it’s important to point out some major differences between CNC routers and 3D printers.

The most important is the differences between the mechanical intent of these machines. CNC routers experience huge amounts of force during milling and rely heavily on the stiffness of the mechanical systems to maintain accuracy. This makes them significantly heavier and slower than a 3D printer. 3D printers on the other hand need to move the extruder nozzle quickly, and because they are relatively lighter than a router or spindle, the mechanical systems lighter and are much more nimble.

While there are several 3D printers which can act as a CNC milling machine, due to the different mechanical requirements of each machine, they are either slow at 3D printing or underpowered as a CNC router. It’s up to the customer to choose if they want a machine that can do one thing really well, or a few things so so.

Regardless of this fact, we still went ahead to see what would happen if we turned the Mill One into a 3D printer!


The first step to modding the Mill One into a 3D printer is to find the right electronics. We had a RAMPS 1.4  control board on hand so we chose to use this. The RAMPS 1.4 has all the sockets and pins needed to control all the periphery devices of a 3D printer (like a hot end, extruder, homing switches). You can find newer, more powerful control boards with many more features that the RAMPS, but the RAMPS is fairly easy to find and can be found inexpensively online.

We followed this dossier to help me wire the RAMPS together and wired the 3 motors which power the X, Y, and Z axis, as well as a spare extruder we had lying around from the old, out of commission Tevo Tarantula. It was quite busted, and some hot glue was to put it together.


Next we made a hotend mount on Onshape ( to mount the hotend and set that up as well. We printed it out on the 3D printer.


As for the hotend, we bought a E3D Volcano hotend clone online for a few dollars. It works pretty well, although if you do use this hotend, make sure to use the fan included otherwise it will clog.


Last thing to do is upload the firmware to the Arduino Mega in the RAMPS 1.4. We used this tool to configure the firmware, which will help you configure the firmware to match the rest of your hardware. It took a bit of trial and error to select the right settings. You can also change some of the settings through the EEPROM settings in Repetier Host (the gcode sender/slicer) we used, in case you need to fine tune things.

Installing the firmware is as easy as selecting the right port and device on the Arduino IDE, extracting the downloaded firmware ZIP file, and opening the Repetier.ino file. Simply click “upload” and the firmware should install onto the Arduino.

There’s a couple more things we could add, like a part cooling fan, homing switches, heated bed, etc. However, we wanted to keep things simple and just prove that it was possible to turn the Mill One into a 3D printer. All in all, the Mill One did a decent job at printing out this little low poly Pikachu. You can see there is some blobbing, which can be fixed with fiddling with retraction settings, and we can improve the pointiness of the ears by adding a part cooling fan.

In comparison to a regular 3D printer, the Mill One is a little bit slower and a little bit louder, but it can still produce high quality prints because the mechanical systems are more rigid and more precise. It was a really fun modification to make and the total cost in parts, had we purchased everything new would be around $60, making it a pretty inexpensive mod as well.

Until next time…



Adding homing switches to the Sienci Mill One, by Troy

With Troy’s instructable, you can now add homing switches to your Sienci Mill One!

What are homing switches? Homing switches allow a machine to touch off of each end of the axis to help find the absolute position within the unit. When the Mill One is first turned on, the current location in which it is at is considered the origin (0,0,0). Until the origin is reset, the machine will consider the movement of the axis to be relative to that origin point. By homing the machine, we can reset the machine to call the same physical position of the endmill to be the origin.

While in most cases, homing switches are not necessary, but in some cases, they can be useful. In a case where you want to make the same part over and over again, it is possible to make a jig to clamp the material in the same position on the bed. By homing the machine, you can set up the Mill One to start milling in the same location of the material every time. This is just one example.

To find out how you can add this feature to your Mill One, visit: