- Things we did -

• Create the CNC structure
• Design the CNC 3D parts
• Build the bed
• Make the motors work
• Make the machine work
• Create some things for details.

We wanted to make a CNC that would cut with a dremel. If a dremel works on this machine, almost every tool would work on this. So we started with the dremel:

About the dremel:

1. Multipurpose rotary tool- From woodworking, carpentry, car care to jewelry making and more; Not recommended for cutting, drilling, or routing.
2. Quick accessory changes – With the patented EZ Twist Nose Cap, accessory changes are easy and done without the need of a wrench. Collet size is 1.8”.
3. Speed range of 5,000 to 35,000 RPM with 6 variable speeds, provides precise tool control and maximum accessory versatility
4. High performance 1.2 amp motor – Provides maximum power and performance at all speeds.

- Steps on the fabrication of this CNC. -

Here is the list of things that we made, this was the first plan and with it in mind, we as team executed every action. In this list you can see every action and a photo:

• Look similar machines to have as reference:


• Determine that we are going to use a DREMEL on this CNC:


• Design the frame and structure of the CNC.


• Design of the 3D pieces that are going to move the DREMEL.


• Create the bed to move on the z axis.


• Cut the tubes in order to make them fit on the structure.

• Test the stepper motors and the software.


• Create a support/cover for the shield and arduino.

• Set on everything on its place and check if it works.

- Material list -

This is the material list of materials that we needed on this machine:

MATERIALS
Material	specification
DREMEL	X
Arduino UNO	1
CNC shield v3	1
MDF	15 mm
MDF	3 mm
3D filament	PLA
acme screw spindle	x4
Stepper motor + spindle	x3
flexible coupling nema 5*8 mm	x3
Sc8uu linear bearing	4
8 mm chrome rod guide	x4

- Parts of the CNC -

Here are the parts of the CNC made by the team:

Structure

The structure of the CNC was made by 15 mm MDF, this because is a thick material that is going to have stability.

This structure is made to move the DREMEL on x axis, y axis and the bed on the z axis.

This is what the file of the design looks like:

The cut on the CNC:

BED

The bed was made by a 3D printed piece and 3 mm MDF. This was measured and was setted with linear bearing and the acme screw spindle. For this process the black piece that moves the bed with the screw spindle, was printed on 3D and then for the MDF bed, 4 layers of MDF were needed, 2 for the screw thread and the other 2 for the screw head.

The design of the bed was made by this two pieces, the first one are the ones that fit with the screw thread and the other one is for the screw head:

3D printed pieces

The 3D printed pieces are needed in order to put the DREMEL and give stability to some parts of the structure:

These 3d pieces need to be assembled and look like this:

The 3D pieces assembled, this are the one that is going to have the DREMEL and is going to move on x axis and y axis.

A final cover for and support for the arduino UNO and the CNC shield.

Stepper motors

The stepper motors need to be on every axis:

For turning on the motors, an external power supply is needed, so these stepper motors are connected to an external power supply.

Code and making the machine work

Now the machine can work by using this source code and using the Universal GCODE sender application. Here is an example and final result:

The final result

This is what we got as result:

Problems during the fabrication

As we fabricated this cnc, we had some problems, the first one was the bed: the linear bearings needed to be well tightened in order to work, if these linear bearings were not at the same height, they won't work well and that happened to us at the beggining. Another problem we found out was that at the beggining we did not consider to let more spaces on the 3D pieces on the rod guide, this was a problem but we re-printed the piece againg giving more space for the rod guide to fit. Finally the vibration made the final carve with some fails.

Possible improvements

• The material of the structure: we could use a better material in order to make the CNC more durable. We only use MDF for almost everything.
• The size: we could make this CNC bigger, this for cutting more kind of material and things.
• Consider connecting the DREMEL and the shield to a same in cnc-connector in order to plug the CNC only in one power supply.

Files

• All the 3D pieces for the DREMEL support.
• All the structure of the CNC (CNC pieces).
• All bed pieces (3D support and MDF cuts).
• The support/case for the arduino and cnc shield.