Week 7 - Joseph Alavez Jaimes - Fab Academy documentation

Group assignment

Here is the group assignment to check more information about the topic computer controlled machining.

1. Basic concepts

1.1 What is a CNC machine?

A CNC (Computer Numerical Control) is a machine that is controlled by a computer to move a tool and cut, drill or engrave materials with great precision.

1.2 Programs used for scanning

This type of computer-aided design CAM software is primarily used for CNC machines. It allows you to import or create drawings vectors and convert them into toolpaths—that is, instructions that tell the machine how to move to cut or engrave a material. I used Vcarve so that is the one that I'm going to explain how to use.

Vcarve.
Aspire.

1.3 Safety measures

To use this type of machine, we must use:

Lab coat
Boots
Jeans
Face mask
Protective glasses

2. Design of the turntable table

2.1 Inspiration idea

For this week I decided to make a table for my turntable. I started my vynil collection on autumn 2025 and I wanted that the vynils can be showed to everyone that enters in my house but all the furniture I saw on internet were always the same bored desing and the vynils were all hiden, that's why I decided to make my own table with the necessities that I had.

Inspired by a search at 2:00 am I found the Display LUNA by Kristian Juul design which had all that I wanted to exhibit my turntable and my vynil collection. So I tried to replicate that design. I also have to mention that I didn't buy this furniture because it is very expensive and out of my range (8,500 DKK that is pretty expensive).

design1_compressed — Fig 01. Display LUNA by Kristian Juul

2.2 Designing the table

In my house I took measures of the space that I have and how it might look at the end.

design2_compressed — Fig 02. The "furniture" for my turntable

I place my turntable and a vynil to see how it would look.

design3_compressed — Fig 03. Expected frontview

Finally I measure the space that the table will supposedly occupy to start designing.

design4_compressed — Fig 04. Expected top view

Here are the measures that I took and drew.

The CAM softwares accept dxf files to make the cut or engrave so I design and assemble the table in SolidWorks.

I first make the half circle and add it the joints with circular pattern for the supports between each half circle. And add it the engrave where the vinyl record holders will be.

design7_compressed — Fig 07. Adding the joints to the half circle

design8_compressed — Fig 08. Final design for the top table

For the supports bettwen I just make a square and add it the tabs for the joints.

KiCad1_compressed — Fig 09. Support design

For the bottom half circle copy and paste the already existing top half circle and just add the cuts of the tabs for the legs of the table.

design10_compressed — Fig 10. Bottom table design

For the legs I repeated the same process as the supports get the shape I wanted and add a tab for the joint.

design11_compressed — Fig 11. Design of the legs

For the vynil record holders I converted the entities of the engrave to extrude the piece, then I add it the cuts to place the vynils and make them as a circular pattern.

Last but not leas I added the half circle for the vynils to be on the same level height always.

design13_compressed — Fig 13. Half circle for the vynils

Here is how the table looks fully assembled.

design14_compressed — Fig 14. Turntable table assemble

My personal touch was at the top, because I created a copy of the file above in case it went wrong or SolidWorks failed; there I added the logos of almost all the Marvel Rivals heroes.

To avoid problems with SolidWorks, I created it in SolidWorks so that I only had to adjust the logo view in SolidWorks. In Inkscape, I added the furniture dimensions, vectorized the logos, and arranged them on the simulated table, resulting in the following.

design15_compressed — Fig 15. Logos in inkscape

The I exported that dxf file to soliwdworks to add the engrave.

design16_compressed — Fig 16. Top table with the logos

Here is the look in the dfx file.

design17_compressed — Fig 17. Draw view of the table

3. How to use Vcarve

3.1 Open the programm

This is the logo of Vcarve we will click it and wait for the pc to open it.

Vcarve1_compressed — Fig 18. Vcarve logo

What appears when we open our program.

Vcarve2_compressed — Fig 18. Vcarve menu

3.2 Configure the workspace

When you opne a new project Vcarve will automatically asl for the dimensions of your material, you just have write them and then click ok.

Vcarve3_compressed — Fig 18. Setting the dimensions of the material

3.3 Import files

Let's import our file, import, import vectors/bitmap.

Vcarve4_compressed — Fig 19. Importing our files

Here is how the file looks.

Vcarve6_compressed — Fig 19. Imported file

3.4 Join vectors

We will select all the vectar that we want to join, then click on the join icon (the square with rounded corners). We must joint them so is easire to work with them like moving them and adding "T-bones"

Vcarve5_compressed — Fig 19. Joining the vectors

Tip: Allign your figure

If it's crooked, we use move and align it with respect to the axis

Vcarve7_compressed — Fig 20. Alligning the figure

3.5 Set up cutting/engraving

We'll go to machine, then toolpath, and choose the type of cut or engraving we want to do. A tab at the right side will appear with the options.

3.5.1 Setting up the engraving for logos

For this engraving, I want it to be detailed, so it won't have much depth; that's why I'm choosing a depth of 1.8 mm.

Vcarve8_compressed — Fig 21. Setting the engravings

Going back to the details, I will use another type of drill bit that is 90 degrees and has a fine point. To modify this tool, we go to the edit button in the tool section and there we change the tool to V-bit and select 90 degrees with a diameter of 12 mm.

grabado_compressed — Fig 22. Changing the tool

We click on simulate, we click accept and it will take us to another window that will show the entire route it will take.

Vcarve9_compressed — Fig 23. Route of the tool

3.5.2 Setting up the boxed with other tool

For making a boxed we select that option and for deep measure we input 2mm and select the boxed shapes. With this we have to change the tool like before, our tool is an Endmill 1/4 so we use that, we will also use this for the cutting.

corte_compressed — Fig 24. Endmill 1/4 tool

3.5.3 Setting up the cutting

For this we will repeat the same proces as before but as we want to cut we will unport that we want to go 13mm down beacause our material is 12mm thick so in that way we ensure that it will be cutted. Then in the tabs button we click it and add 5 tabs so when it is almost cutted the machine leaves a small quantity of material so the material is not fully cutted in order to not get a piece crooked.

In total, I will have 4 types of cuts/engraving:

Carving: We will engrave (in my case, the logos).
Boxed: Makes holes.
Inside: Makes the cuts for the joints.
Outside: Makes the cuts on the outside to separate the parts of the furniture. In this option, it is important to add tabs because they prevent the cut from detaching completely from the material, ensuring it doesn't end up crooked.

3.6 Making the T-Bones

When you cut an internal square with a CNC, you have to make T-bones because the cutting tool (the milling cutter) is cylindrical and has a diameter, so it cannot create perfectly 90° internal corners.

T-bones are small circular extensions added to the inner corners of the design to accommodate the cutter radius, allowing square pieces to fit together correctly after cutting. In short, they are used to compensate for the geometric limitations of the CNC cutting tool.

For making them we will click on the create chamfers logo and then we click on the cornes, thay will automatically appear.

Vcarve11_compressed — Fig 26. Making the T-bone

Here is the final result in 2D

Vcarve12_compressed — Fig 27. File in the paper

Here is the final result on a 3D view or the material

Vcarve13_compressed — Fig 28. File on the material

3.7 Save the route for the CNC

We will have 2 files for the instructions and remember to always start from in to out. We save both files the same way save a file in "AsiaRobotica 3-arcs", you have to select the option "visible paths of a file"

Vcarve14_compressed — Fig 29. Saving the files for the routes.

3. Using the router

3.1 Get your material

Move your material to the CNC

cnc1_compressed — Fig 30. Moving the plywood

3.2 Turn on the machine

To turn on the machine, simply pull out the emergency stop button and press the power button to turn it on. I will use the ASIA Robotica machine

We can move our tool with the control buttons; using xy=0 will set our origin.

Vid 01. Moving the tool

3.3 Place your material

We will place the material on top of the sacrificial bed.

cnc4_compressed — Fig 31. Placing the plywood

We put our locks or clamps on so that our plywood doesn't move.

cnc5_compressed — Fig 32. Putting the clamps on the plywood

3.4 Change the tool tip

We changed our tip so we could do the engraving first (because the order for the products to come out well is from the inside out)

cnc6_compressed — Fig 32. Tool tips that our machine has

To change the tip, turn each nut in the opposite direction and the tip will come out.

Vid 02. Moving the tool

3.5 Adjust the z axis

We manually adjusted our Z-axis tool because when we used it, the tool wasn't touching the plywood, so we had to adjust it. We simply loosened the screws holding the tool, and once it was at the required height, we readjusted them.

cnc8_compressed — Fig 32. Screws that had to be loosened

Now that is touching the plywood we can readjust the screws

cnc9_compressed — Fig 32. Tip touching the plywood

We'll do a short test to check that we're recording correctly. To do this, rotate the tool and slowly lower it to the desired depth. To set the origin to z, use shift+xy=0

Vid 03. Testing the Z axis

3.6 Selecting our file

To use our file, insert your USB drive. The machine will detect and open it. Locate your file and select OK, then press 3 to copy it. Press Esc until you return to the first menu. Use the list button, select USB Files, find your file, select it, press 1 (load), and finally press play.

Vid 04. Selecting the file from my usb

3.7 Start engraving and cutting

After it is calibrated we start engraving and the the cutting.

Vid 05. Engraving of the first logo

This is what the engraving of all the logos looks like.

cnc13_compressed — Fig 33. Engraved logos

This is how the final pieces turned out.

4. Post-processing

4.1 Sand your pieces

It is important to sand the pieces because it helps us to give a better finish when applying paint, stain, etc.

postprocess1_compressed — Fig 35. All the pieces before sanding

Remember to use all the safety equipment.

postprocess2_compressed — Fig 36. Me with the safety equipment

Here at Ibero we have a sanding machine with which I removed the wood burrs that had remained.

postprocess3_compressed — Fig 37. Sanding the support from the sides

postprocess4_compressed — Fig 38. Sanding the face from the support

I have to do the sanding of the joints by hand.

postprocess5_compressed — Fig 39. Sanding the joints

4.2 3D print the vynil supports

I 3D printed the vynil supports in a Prussa XL.

postprocess6_compressed — Fig 40. Vynil supports in the prussa software

Fig 41. Vynil supports printed

Finally, to close the pores, I used 400 grit sandpaper, and here is the result.

4.3 Paint the pieces

To paint, I used chocolate-colored oil paint, applying 3 coats.

1st coat

postprocess10_compressed — Fig 43. 1st layer of oil paint

Comparisson with one layer and two layers.

postprocess11_compressed — Fig 44. 2 layer vs 1 layer

Here is how the top table look with 3 layers. For the top of the table, as suggested by a teacher, I will decorate it using colored crystal resin to paint each character's logo.

postprocess12_compressed — Fig 44. 3 layer top table

4.4 Apply the resin

For the top of the table, as suggested by a teacher, I will decorate it using colored crystal resin to paint each character's logo.

postprocess13_compressed — Fig 45. Crystal resin, paint and pigments

The manufacturer's instructions state that for every 100g of resin, 40 drops of catalyst are needed; therefore, since I prepared less of this mixture, I will use the corresponding number of drops.

Now I must emphasize that because I wanted to make a very small mixture, the catalyst couldn't act since the heat generated was absorbed by the container; that's why the photos show a very low weight.

Recomendatino for a small quantity of resin

So my recommendation is to make at least 30 grams; mix it from there, and it works perfectly, taking 30 minutes to dry if using pigment and 40 minutes to dry if using acrylic paint.