Week 07: Computer-Controlled Machining

Group Assignment

Complete your lab's safety training Test runout, alignment, fixturing, speeds, feeds, materials and toolpaths for your machine.

We went over the safety procedures of the woodshop in general, and the large shopbot specifically. Our group compiled our notes and photos on our group page.

I love working with this amazing group of women. Never have I had such a balanced team. Each of us took notes and pictures, which we compiled simultaneously as we worked next to each other, on our own computers using a google doc. How strange it is that we could all be talking and typing at the same time, and watching the document change before our eyes. It is interesting to see what parts of our safety training stuck out to each of us. For instance, I focused on nothing dangling near the machine, hair, id tags, etc, while another made absolutely certain we stayed behind the yellow line, and another made sure we remembered to call out our actions to others in the room.

It is interesting to think of how our personal experiences and fears make certain safety procedures stick prominently in our minds. I have long hair, and the warning Neil gave has made me very cautious. Angela has to keep kids away from equipment regularly, and regularly enforces the importance of safety lines. Camille, has experience with robotic competitions with kids. I'm sure announcing your actions is likely a key safety procedure she practices. Kim jumped right into writing up procedures, her fear was having issues because of user error, which matches her computer programming background.

Of course we know the most important safety rules: - wear PPE, and no loose clothing - don't be alone - don't get close to a machine that is running - always know where the emergency shut off is.

Settings on our school's Shopbot are preprogrammed. But should I want to use a material like solid white oak, that is very hard, I would need to slow the feed down, and decrease the depth of each pass. Moving too fast or cutting too deep through a material could cause the bit to break.

On Tuesday we learned to use the Shaper CNC router! I was very excited to try it! It uses .svg files or you files from the studio program. You can also create a file directly on the machine. Mr. Dubick ran through the procedure quickly, and let us play. He says it is a very safe tool that he will let middle schoolers use. The programming stops the cut if you go off track, and it will not work unless both hands are on the machine.

You can set the cut to be outside, inside, pocket. I wonder if you can create multilayer toolpaths with multiple drill bits? If you were to create an svg file with multiple offset lines I don't see why you couldn't. You would have to keep track of your paths, and desired drill bits, and change the depth setting and/ or drill bits for each path. Possible, but even with the guidance of the Shaper3D, it is difficult to get perfect cuts.

Individual Assignment

Make (design+mill+assemble) something big

Preparing my CNC Shopbot cut file

I started by wanted to try a living hinge on my cabinet, but wanted to test it first. I asked Claude.ai for recommendations on where I could find a print file so I could test out the hinge. I talked with Mr. Dubick about the practicality of using living hinges on my cabinet. He didn't recommend it. So I put that idea on the shelf, and went back to my original design.

In my chat about the living hinges Claude offered to write a code to make the cabinet in Fusion360. I decided to work with an AI program to design my simple cabinet so that I could spend my time altering the project using the tools I have not yet learned.

I was proud of myself for making this decision, but then I felt guilty. So I spent time making it myself in fusion, but kept getting so upset with the program. I don't get nearly as frustrated fixing a file that Claude created as I do fixing my own. I believe that is because I expect more of myself than I do from others or programs. That is, in creating a Fusion design, the design software gets no grace from me, it should work as expected!

Whenever I created a new component I had to define my parametric functions again. So my whole design is not truly parametric! This was the point when I took a break from Fusion, and edited Claude's files in Aspire.

• I later went back to Fusion, see below for attempt 100ish. Claude.ai did a good job, but like Meshy.ai, referenced later, it kept getting stuck on particular issues. Claude had lots of problems with the joints. It was like it flipped the 3d into 2d on the same plane.

I was pleased at how fast it took what I asked, and made the file. I wanted it to be parametric, so it created a file to make the code parametric as well. Here is a summary created by Claude of our creation of the cabinet .dxf file.

I ended up making 9 versions, and editing it myself in aspire. Aspire is limited, but I am great with boolean design.

Here are a few of the design flaws: - strange rounded joints

• holes for caster wheels too close to joint

• only inny joints

• lines not connected

I fixed all joints so that they matched each other, and the thickness of my wood, which was measured to be 0.46 inches. This was done in Aspire.

On Monday: I went back to Fusion determined to accept the limitations of Fusion, and of myself.

After looking up the parametric variable issue, and found a fusion360 tutorial on importing your parametric functions by creating as master file, favoriting them, and using derive to import them.

I couldn't get derive to work. Or the other ways the tutorial suggested. Instead of continuing to work on this problem I accepted that my parametric file would not truly be parametric. I am choosing to believe that my efforts didn't work because of the fusion update so I can let go.

I was able to get all my parts to be components!!

I used the mirror function to make the back piece, but it caused me troubles, because of the line in the middle.

I didn't trust that I had actually created the file correctly until I moved the components!

fusion magic table file

Preparing the Aspire file

I refreshed my memory on using Aspire by reviewing an example from our pre-fab class when we made topographical carvings using Aspire and the Maker Cavera ATC. I turned mine into a decorative box as a gift to my husband.

Click here for the tutorial with my notes.

I set up the file when I imported my project. Making sure to input the dimensions of the plywood.

I made sure that all the vectors of each object were joined.

My fusion file that was created with the mirror feature, gave me trouble. I had to go back to Fusion, and do make each tab individually.

I then created a toolpath following a previous tutorial. Making sure to set the material thickness as 0.46 inches from my measurements.

To my files I added dogbone to the corners with 90 degrees or less angles. This allows for the tool to cut all of the joint so that the attaching piece fits in. Remember the attaching piece is rotated so that the side with the vertical cut will enter the adjoining piece. It cannot fit if the cut is curved. - I used .125 inch dogbone corners in the fillet menu, as my cut will be made by a 1/8 inch drill bit.

My first toolpath is for the shelf holes. They are 1/4 inch so that I can just drill down with the 1/4 inch drillbit. I choose the drill holes option, choose the 1/4 inch drill bit for the Shopbot, and enter my depth of drill to be .3 to match shelf peg measurements I found online.

Next I select all the outside cuts, and choose the profile cut in toolpath, with the 1/8th inch drillbit. I added tabs along the outside of my pieces, at least 3 per piece. There is also an option for automatic tab placement.

I make sure to label my toolpaths with my name and path information so that I can easily find it in the downloads folder. I preview the toolpaths to make sure they are correct, and save the files.

aspire file

Cutting on the Shopbot

I make sure the Shopbot is ready for me, by checking with an instructor. It had already run the initial warm up, and was ready.

With help, I load my material, making sure to align the front corner to (0,0) on the table, and that the bow of the material is up. I then use the nail gun loaded with 1" composite nails to hold down my material

I set the z home to be 2 inches by using the command

jz 2 zz

Then I opened my toolpath file for my holes in the Shopbot program.

I press enter to run my program, and when prompted, I start the drill.

I watch my aircut for a few seconds to make sure it looks correct. Then I press the space bar to stop the program. Quit the cut, and re-home the machine using the command

c3

Then I start my file again.

Once the Shopbot had finished, I cut the pieces free of the tabs, and remove my material by hitting it with a mallet to shear off the nails.

I sanded my pieces with the orbital sander, and cleaned up the work area. Meanwhile Mr. Dubick ran the "end of day routine on the Shopbot."

I brought my pieces home to assemble. My cabinet assembled perfectly without glue or screws, except for one joint issue.

I lined up the side joints on the top and bottom pieces backwards so I had to cut the tab to assemble the cabinet.

Even with these joints just, I can lift the cabinet by the top piece without it falling apart!

My second cut using the Fusion file I created had 2 issues. 1. I missed a constraint on the top and bottom pieces so they were a bit short. Surprisingly, I can still lift it by the top piece without it falling apart.

1. for some reason my cut was set too far to the left. like it had been shifted along the y axis. it was only a few inches so I missed it in the air cut. I had to use the space bar to stop the cut when it got too close to the edge. I moved the piece in aspire, and quickly remade the toolpath. Then I saved, and cut it. It worked great! with the one exception of the too short top and bottom.

I looked up this issue, and found a fusion360 tutorial on importing your parametric functions by creating as master file, favoriting them, and using derive to import them. This didn't work, and I am wondering if it is because of the fusion update.

I was so happy that the lecture this week spoke about more than just CNC designs. I am new to woodworking, but have really enjoyed learning to wood turn simple projects over the past 2 years.

Since I am a small person of limited strength the idea of making projects out of full sheets of plywood is not feasible. I prefer to work with materials I can move on my own. Furthermore, I would love to alter premade furniture. I enjoy thrifting, and some older furniture is made from beautiful wood that is a shame to waste. Making use of unwanted things gives me great joy.

I used Meshy Model Helper to create a prompt for a floral relief panel, based off of a painting I made of purple flowers.

"A richly detailed carved panel, rendered in high relief from cherry wood with an unvarnished surface, depicting five gently curved, slightly overlapping lavender stalks. Each stalk features densely sculpted flower heads, mimicking thick impasto. Slender stems rise from a base of broad, sweeping carved grass. All set against a light background with smoothed marks from hand carving. The scene is illuminated by soft, diffused daylight, viewed straight on with a shallow depth of field, presented in grayscale with high tonal contrast and deep, defined shadows."

The first generation was amazing!

But I had it set to the Meshy 6 setting, and had to do it again in Meshy-4 which is free. It was still rather good, and my tools probably can't make the small details anyway. I will add those with hand tools.

My daughter had to make a diorama for class that included a kitten-dragon. So I showed her how to make a model with Meshy.ai. Bonding with my daughter, and practicing what I am learning, win-win! Of course the free renderings were pretty bad, and I ran out of free credits. So I now have an account for Meshy.ai.

Now with the paid version I was able to make this dragon carving. It was incredibly hard to get Meshy to understand what I wanted, and the ai helper was not being very helpful. I tried 13 times with text, and 2 image to prompt to try to improve my prompts. It is frustrating when the program seems to get stuck on a detail opposite my prompt. For example I wanted the wings outstretched, and I kept getting wings tucked in. I tried outstretched, fully outstretched, fully extended, on a rectangular panel (to give the wings more room), but none of that worked.

My final prompt was, "a relief carving of a direct overhead view of a small dragon's back flying over clouds."

dragon carving file