Skill Builder: Milling pt.2
Baby Anarchist Sticker Designed by Ocean Gao (@baby.phag) http://www.oceangao.com/buy/baby-anarchist-sticker
Week 3 Skill Builder:
For this week’s skill builder I was inspired by my favorite sticker— Baby Anarchist by Ocean Gao [1]. Initially in thinking about creating inner locking pieces I thought it would be really cool to recreate the rainbow/sparkles portion of this sticker with each of the text pieces also being an insertable piece. Quickly realized that was something I would need to work up to so I decided to start with just making a rainbow tag with inner-locking arcs that would sit snuggly inside of a larger cutout.
Supply List:
Vectorworks Software
Adobe Illustrator
Plywood
Digital Calipers
Other Mill
1/16” Flat End Mill
Double Sided Tape
Sandpaper
Acrylic Paint
Wood Glue
Wood Wax
Vectorworks:
To make the six arcs in Vectorworks I used the Polyline Tool to create a series of arcs and then connected the inner and outermost arcs with a line that intersected with each arc. I was then able to select various combinations of arcs and straight lines and create surfaces from these for each arc I would need to cut out, as well as the whole silhouette of the rainbow. I then used the offset tool to copy each of these arcs with a -.002” offset. Originally I had planned to have a single perimeter piece that all of the other arcs would sit inside. For this piece only the inner archway was offset +.002”.
I saved this document as a DXF and opened it in illustrator. While here I discovered that my process had created a series of stroke-less arcs or misplaced points that I couldn’t see so I had to clean up these before I could save it as an SVG. Once that was all tidy I laid out my arcs across the artboard. I positioned them with some nestled in between one another hoping to reduce material waste.
Milling:
I started off with a single piece of plywood I had left over from last year and cut it down into two pieces small enough to fit on the surface plate of the mill plus a little rectangle I thought would be of use.
I did the basic set-up steps: measured the material and input these values into the program, taped it to the plate, homed the machine, touched off and set the the tool.
Surprisingly, the program accepted the one SVG file with all of the arches so I didn’t have to do much placement adjusting.
With that I started running the program. The first few passes seemed okay, but during the last pass things started to go awry. Because the parts were so light, thin, and tucked in side of each other many of them flew out of position as the last pass, cutting them out was made. Some broke. Some ended up not being fully cut out. It was a mess.
For my next attempt I uploaded each arc as an individual SVG and adjusted the X and Y placements for each one.
A couple of arches again made a break for it while the spindle was in motion (pictured below) but because they were not nested inside each other and were more appropriately spaced none of the pieces were lost.
The perimeter piece I had designed was too thin and wouldn’t come out so at this point I altered the design, instead going for a rainbow shaped pocket that would sit inside a circular pendant. The six arches would sit snuggly inside of it and slightly higher than the surface of the circle creating a cute little relief.
During the last few arcs I ran into some issues with the tape holding the wood down. I ended up abandoning two of the arches and cutting them out on a new piece of material — that extra little rectangle I thought I wouldn’t use at the beginning of this job.
With all the pieces cut out I attempted to fit them into the engraved pocket. The arches feel like the fit together and are quite snug. They fit together better when oriented in the same direction they were cut. Only the very last arch didn’t sit fully seated in the pocket, but a bit of sanding helped remedy that.
I sanded each of the arches and the pendant with a range of sandpapers up to 320 grit. Then to finish things off I painted each of the arches with acrylic paint for a more vibrant final product
Conclusion:
I feel like this time around I got much more experience with what could go wrong in a milling project: tape not secure enough, finished parts breaking in the machine, issues with the layout preventing cuts from being completed.
Some of the decisions I made thinking it would move things faster or save material really backfired, which is something to keep in mind for next time. Going slower and having more control will lead to better outcomes with this process.
There was also one weird thing that happened that maybe should be checked out. I clicked pause in order to vacuum out the machine during a run and it didn’t pause. The scree indicated that it was paused by greying out the pause button and highlighting the play and stop options but the actual machine didn’t stop running.
Sources:
