Weekly Assignments Final Project About me

WEEK 07

Computer-Controlled Machining

How the week started

I was intrigued to start this week as this was something I wanted to try out for a long time, to make something out of wood or plywood. Though my agenda was to design a laptop stand which could be moved around with ease and rotated. I didn’t make it cause it would need other components to do it and I wasn’t ready to design within a short period of time. So that is gonna continue as my dream project.

How the week ended

This week was hectic, I spent a lot of time designing, editing, redrawing, despite burning the midnight oil, I am somewhat unhappy with my workflow. the fun part of the week was being taught about CNC machines, materials, workflow by, Mufeed Mohamed and Revisankar S . I did a mistake of forgetting to turn on the exhaust of the laser cutting machine and it started to fume up immediately. I stopped the machine immediately.

Week 07’s Assignment

Group assignment:

  • Complete your lab’s safety training.
  • Test runout, alignment, fixturing, speeds, feeds, materials, and toolpaths for your machine.
  • Document your work on the group work page and reflect on your individual page what you learned.

Link to group assignment

Individual project:

  • Make (design + mill + assemble) something big.

Workflow

CAD (Fusion) → Scaled Model Test by Laser Cut → Assemble Model
↓
CAM (Set Tool Path) → Cut → Sand → Assemble Model

Brainstroming designs

Initially I wanted to design something for my cats, a kerf bend cat perch. Something that could be removed and disassembled with ease. Then I stuck to a simple shape without any kerf bends. As I started to design in unfamiliar software Fusion, we were shared a few Fusion tutorial videos (1, 2, 3) so we could get a better hold of the software. It definitely helped me a lot. I chose another project that felt simple initially.

Brain stroming

1 / 5 Inital sketch for a cat stand
2 / 5 I tried to recreate this design.
3 / 5 Sketched the cat house to understand the joins
4 / 5 Understanding the panel joints
5 / 5 There are changes in teh design bu these helped when designing in fusion
Inital sketch for a cat stand I tried to recreate this design. Sketched the cat house to understand the joins Understanding the panel joints There are changes in teh design bu these helped when designing in fusion

I settled down to a triangular cat house, inspired from a Pinterest search. The design looked simple. I came across issues with the model. Finding the order in assembling the model, angle to cut the slot in what a pocket hole is, because the slots didn't go in otherwise.

Fusion - troubled waters

The unfamiliarity with Fusion continued this week, yet got a better hold of it than the last time I used it.

Layout setup

1 / 2 The workspace is hybrid.
2 / 2 This time I faced an issue with the units having a comma instead of the dot, it was confusing, so I changed that by going to Preferences → Unit and value display → decimal point display changed it from 123,454 to 123.45. The unit is still mm. Click apply and click okay.
The workspace is hybrid. This time I faced an issue with the units having a comma instead of the dot, it was confusing, so I changed that by going to Preferences → Unit and value display → decimal point display changed it from 123,454 to 123.45. The unit is still mm. Click apply and click okay.

While drawing the model, I chose the front plane and constructed an equilateral triangle so that all the sides would be equal. I then offset the equilateral triangle to the plywood thickness.

Front panel design

1 / 5 Draw an equilateral triangle 500mm
2 / 5 Offset outside to ply thickness
3 / 5 Creating the front panel
4 /5 Select the shaped to extrude,selectfaces by pressing shift
5 / 5 Extrude the front panel to ply thickness
Draw an equilateral triangle 500mm Offset outside to ply thickness Creating the front panel Select the shaped to extrude,selectfaces by pressing shift Extrude the front panel tot ply thickness

Setting parameters for the thickness helps in adjusting the model to suit the stock we use. In our case, we used 12 mm plywood.

An error to remember

Red Flag: The mistake I made here was linking all my values to plythickness. I thought that by doing so the whole model would automatically adjust, but when I completed the model and applied the parametric change it affected the model a lot. Some constraints were missing and the geometry shifted.

From this I learned to use the parametric value only for plythickness and not for other measurements. If needed, I can create another parameter with the same value but give it a different name.

Here I extruted the area using plythickness. this was unnecessary , I could have done with a defined value.

I added the side panels. I initially took a more complex approach to draw this. I extruded from the slot in the front panel and then extruded it sideways to create the side panel. After that, I had to combine the bodies.

This could have been done in a simpler way by extruding directly from the first sketch. In the dialog box, set the Extend Type to "To Object". It is also better to change the Operation to "New Body" most of the time; otherwise, the body may automatically join with a nearby body, which we do not want.

This could have been done in a simpler way by extruding directly from the first sketch and then using Modify → Combine → Join.

Perforation

This is one step I am glad that I learned. When two objects are connected by a slot, we first select the blue body. This is the body that needs to be perforated.

Go to Modify → Combine. Select the target body (the body to be perforated), and then select the tool body. There can be more than one tool body.

Remember to check "Keep Tools" so that the tool body remains even after the cutting operation.

Perforation setup

This is one step I am glad that I learned. When two objects are connected by a slot, we first select the blue body. This is the body that needs to be perforated.

1 / 5 Go to Modify → Combine. Select the target body (the body to be perforated), and then select the tool body. There can be more than one tool body.
2 / 5 Remember to check 'Keep Tools' so that the tool body remains even after the cutting operation.
3 / 5 Go to Modify → Combine. Select the target body (the body to be perforated), and then select the tool body. There can be more than one tool body.
4 / 5 Go to Modify → Combine. Select the target body (the body to be perforated), and then select the tool body. There can be more than one tool body.
5 / 5 Go to Modify → Combine. Select the target body (the body to be perforated), and then select the tool body. There can be more than one tool body.
Go to Modify → Combine. Select the target body (the body to be perforated), and then select the tool body . There can be more than one tool body. Remember to check 'Keep Tools' so that the tool body remains even after the cutting operation.

Scaled Model Testing

I would say this step is crucial when you are designing something for the first time. This helps to understand how to fix the model and what difficulties I might face.

The model is cut in cardboard using the Trotec Speedy 100 laser cutter Learn More

1 / 4 The model was scaled down and cut using a laser cutter.
2 / 4
3 / 4
4 / 4 I could not fix the side panel in the middle model. I used pockets to join the side joints. The third prototype worked with the pockets.
The model was scaled down and cut using a laser cutter. I could not fix the side panel in the middle model. I used pockets to join the side joints. The third prototype worked with the pockets.

Nifty Dogbone

Download the Nifty Dogbone tool from Autodesk Marketplace Download

A dogbone is applied, otherwise the 6mm bit would leave a curved corner inside at the right angle connections. This would make it difficult to connect or join the pieces. Dogbone allows the tool to cut into the inside right angle joints.

1 / 5 Download the tool
2 / 5 Complete the setup
3 / 5 In toolbar select Utilities > Add-ins > Scripts and Add-ins > NiftyDogbone and make it visible
4 / 5 Select Modify > Nifty and select the corner to apply the dogbone, tool diameter is 6mm
5 / 5 Joints where dogbones were applied
Download the tool Complete the setup In toolbar select Utilities > Add-ins > Scripts and Add-ins > NiftyDogbone and make it visible Select Modify > Nifty and select the corner to apply the dogbone, tool diameter is 6mm Joints where dogbones were applied

Preparing the File for CNC Routing

The plywood I used was not exactly 12 mm, but 11.3 mm. As I had mentioned earlier, I did not use the parametrics correctly, so I had to scale the model using a scale factor of 1.04634.

1 / 5 The plywood's thickness was measured at different points.
2 / 5 The average plywood thickness was 11.3 mm, so the model was scaled using a factor of 1.04634.
3 / 5 Modify > Arrange tool. Using this tool, choose the face that will be facing up during routing.
4 / 5 Click the letter P or use Project to create faces for the toolpath to follow. Set the envelope to 8 ft × 4 ft, which are the dimensions of the plywood sheet.
5 / 5 Finish the sketch, then right click on the sketch and select Export as DXF. This is the file format used for CAM in the ShopBot.
The average plywood thickness was 11.3 mm, so the model was scaled using a factor of 1.04634. The plywood thickness was 11.3 mm, so the model was scaled using a factor of 1.04634. Modify > Arrange tool. Using this tool, choose the face that will be facing up during routing. Click the letter P or use Project to create faces for the toolpath to follow. Set the envelope to 8 ft × 4 ft, which are the dimensions of the plywood sheet. Finish the sketch, then right click on the sketch and select Export as DXF. This is the file format used for CAM in the ShopBot.

Using the Arrange tool is crucial because the pockets need to be machined on the inner side of the panels. The correct face must be selected as the top face before arranging the parts on the sheet. The envelope was set to 8 ft × 4 ft, which matches the dimensions of the plywood sheet being used.

Safety Measures

  • Before stepping foot into the woodworking area or operating the ShopBot, the safety measures mentioned in the image and the use of safety shoes are mandatory.
  • No loose attire, as the spindle rotates at high speed and might cause accidents, among other possible ways things could go wrong.
  • While near the machine, maintain distance when setting the axes.
  • Ear protective gear is important, as the CNC machine and the vacuuming process can produce loud noise.
  • Do not leave the machine unattended or use your phone mindlessly.
  • In case of any emergency, slam the red button to stop the machine.
  • Operate the machine with utmost care.

Also, this photo was taken during my final project's sanding stage. Since time travel is not known to me yet, I could not go back and remind myself to take a safety photo during the CNC operation.

ShopBot PRS5 Alpha

Machine Details

1 / 3 This machine is considered to be the OG machine for routing. The longer side is the X axis and the other side is the Y axis. Z is the up and down motion.
2 / 3 These are the switches to be flipped up to turn on different parts of the machine. The machine is turned on first, then the axes are set. The spindle and vacuum are turned on only after this.
3 / 3 The vacuum brush sucks out as many chips as possible. There are two sacrificial beds placed on this machine. One comes with the machine, and another sacrificial bed is placed on top of it. The stock is placed on the sacrificial bed.
This machine is considered to be the OG machine for routing. The longer side is the X axis and the other side is the Y axis. Z is the up and down motion. These are the switches to be flipped up to turn on different parts of the machine. The machine is turned on first, then the axes are set. The spindle and vacuum are turned on only after this. The vacuum brush sucks out as many chips as possible. There are two sacrificial beds placed on this machine. One comes with the machine, and another sacrificial bed is placed on top of it. The stock is placed on the sacrificial bed.

VCarve Pro

VCarve Pro is software used to create and cut designs on a CNC router. It is paid software and helps to control the toolpaths.

Yep there are 19 images! 😁 and it did take a long while to type it all 🥲.

1 / 19 Open the software and create a new file.
2 / 19 In Job Setup, set the material thickness and the size of the stock. Then, in Step 2, import the DXF file.
3 / 19 In Edit Objects, use the Move tool. The bed represents the size of the stock.
4 / 19 Place drill spots so that the spindle does not hit the screw heads or screws.
5 / 19 The diameter should match the tool bit diameter.
6 / 19
7 / 19 The tool name and diameter must be cross checked in the Tool Database on the right side. Flat End Mill, 6mm.
8 / 19 The cut depth determines how much the tool cuts into the stock. The stock I used had warping issues due to moisture retention.
9 / 19 The toolpath is shown.
10 / 19 The drill points.
11 / 19 Here, the pockets are used to completely remove the stock in that area. The cut depth is set greater than the material thickness. The number of passes is three.
12 / 19 The toolpath passes and the depth for each pass are shown.
13 / 19 This is because the material thickness is less than the cut depth. I am aware of this, and the sacrificial bed will handle the tool.
14 / 19 This is named Pocket 1. The toolpath and material removal are shown.
15 / 19 The toolpath used when cutting the pocket is shown.
16 / 19 The last toolpath operation is cutting out the outline.
17 / 19 The toolpath used to cut the material free is defined. Tabs are added so that the part does not come off completely. Tabs should be placed on the longer straight edges rather than at joints or curved sections. This helps achieve a better finish.
18 / 19 The tab size is defined.
19 / 19 The tool depth used to cut through the material is set deeper than the material thickness.
Open the software and create a new file. In Job Setup, set the material thickness and the size of the stock. Then, in Step 2, import the DXF file. In Edit Objects, use the Move tool. The bed represents the size of the stock. Place drill spots so that the spindle does not hit the screw heads or screws. The diameter should match the tool bit diameter. The tool name and diameter must be cross checked in the Tool Database on the right side. Flat End Mill, 6mm. The cut depth determines how much the tool cuts into the stock. The stock I used had warping issues due to moisture retention. The toolpath is shown. The drill points. Here, the pockets are used to completely remove the stock in that area. The cut depth is set greater than the material thickness. The number of passes is three. The toolpath passes and the depth for each pass are shown. This is because the material thickness is less than the cut depth. I am aware of this, and the sacrificial bed will handle the tool. This is named Pocket 1. The toolpath and material removal are shown. The toolpath used when cutting the pocket is shown. The last toolpath operation is cutting out the outline. The toolpath used to cut the material free is defined. Tabs are added so that the part does not come off completely. Tabs should be placed on the longer straight edges rather than at joints or curved sections. This helps achieve a better finish. The tab size is defined. The tool depth used to cut through the material is set deeper than the material thickness.

Saving Toolpaths

The toolpaths are saved as two different files.

1 / 4 Here, the drill path is saved separately so that after the points are marked, I can screw the stock to the sacrificial bed.
2 / 4 The file is saved with the name shown. The file format is .sbp.
3 / 4 The rest of the toolpaths are saved together. Since the stock is fixed, the machining can be completed in one flow.
4 / 4 The toolpath.
Here, the drill path is saved separately so that after the points are marked, I can screw the stock to the sacrificial bed. The file is saved with the name shown. The file format is .sbp. The rest of the toolpaths are saved together. Since the stock is fixed, the machining can be completed in one flow. The toolpath.

Job Control - Setting Zero Axis

1 / 7 These are the controls. The X and Y positions have to be set first.
2 / 7 The control box is near the system itself. One has to press the reset button to start.
3 / 7 The tool is moved to the machine's zero axis.
4 / 7 The new yellow keypad dialog box is where you control the spindle's movement. The arrow keys on the keyboard are used for movement.
5 / 7 Click Zero Axis to open this dialog box. The first image is before setting the axis. The second image is after setting the X and Y axes.
6 / 7
7 / 7 Move the spindle away from the set X and Y axes. This is to check the Z axis and register the Z axis zero. The plate is removed from the slot and placed under the spindle, and the alligator clip is clipped to the spindle. Then click OK.
These are the controls. The X and Y positions have to be set first. The control box is near the system itself. One has to press the reset button to start. The tool is moved to the machine's zero axis. The new yellow keypad dialog box is where you control the spindle's movement. The arrow keys on the keyboard are used for movement. Click Zero Axis to open this dialog box. The first image is before setting the axis. The second image is after setting the X and Y axes. Move the spindle away from the set X and Y axes. This is to check the Z axis and register the Z axis zero. The plate is removed from the slot and placed under the spindle, and the alligator clip is clipped to the spindle. Then click OK.

Route CNC

Finally, let's route it.

Yeah, it was a really long process, and then there is the process of post processing.

1 / 4 Click Cut Part to open the drill file.
2 / 4 Click Start to make the drill points.
3 / 4 Upload the next file to route the pockets. Then upload the full depth file. This cuts through the stock entirely.
4 / 4 Notice that these are Pocket 1 and Profile 1, which cut through the stock.
Click Cut Part to open the drill file. Click Start to make the drill points. Upload the next file to route the pockets. Then upload the full depth file. This cuts through the stock entirely. Notice that these are Pocket 1 and Profile 1, which cut through the stock.

Drilling

Routing/h3>

Chiselling

Since the stock had a warping issue, it did not cut through the material fully. I had to chisel it out using a chisel and hammer.

Sanding

After chiselling, I had to sand the parts. I used a handheld sanding machine.

Issues

1 / 2 The pockets did not go through the material. I chiselled out as much as possible.
2 / 2 Used a Dremel to cut the holes.
The pockets did not go through the material. I chiselled out as much as possible. Used a Dremel to cut the holes.

Assembling the parts

Use of mallets to hammer the joints together as the fit was tight.

Hero Shot

1 / 4 The front view.
2 / 4 Left side view.
3 / 4 Back view.
4 / 4 Right side view.
The front view. Left side view. Back view. Right side view.

Lift test

I was able to lift the pet house by holding the handle.

Download Week 7 Zip File