Navigating the Challenges of a Solo CNC Project

I had no previous experience with CNC before the BIOE 555 classes.  Thankfully, I had the support of Pablo, and lab assistants. Also with Ric we had the chance to do a test run together, grasping the Shapeoko Pro XXL. We were able to cut an apple shape together in our test run. My goal was to make a mug coaster that I can use at home as well. This project was a rollercoaster of emotions – frustrating, yet ultimately rewarding.

The Fickle Nature of CNC

Working with the Shapeoko was no easy task the machine is hard to optimize and tends to stop just before starting with the work making you start the whole process over again and taking too much time of yours. The experience was a stark reminder of the importance of early and consistent learning. Cramming knowledge just before deadlines simply doesn’t work.

Design Choice

My plan was to make a mug coaster with Rice logo on it, also I planned to laser engrave the bottom of it. I have measured the bottom of water glasses I have at home to sketch up my design. However while working with the CNC I realized the original dimensions are taking too much time thus I decided to create two smaller versions for the assignment. I sketched my design in Adobe Illustrator. The inner diameter of the original design is 2.85 Inches and the outer diameter is 3.10 inches. I ended up making a big one to be used by me later.

 

CUTTING THE PIECES

The challenge began with sourcing the right softwood. With the help of a lab assistant I was able to select a softwood thin enough to be used as a coaster. Later I cut the softwood to 5*10 in dimensions. I have installed the wood on the CNC milling surface using two sided tapes and plastic holders. Later I have set the turned my sketch into G-Code that I can use with the CNC.

PoST PROCESSING

After the cut I have used 80 grid sandpaper to sand the surfaces of my shapes. Also I have used files to get rid of the rough artifacts left by the CNC’ing. I have used Epilog Fusion Pro for laser engraving Rice logo and my name on the original (Big) piece.

I really think liked the way wood looks and didn’t want to paint it. Thus, I have only polished the surface of my pieces with Watco Rejuvenating oil.

 

Reflecting on the Journey

This project was challenging not just because of the technical aspects, but also the uncertainty of outcome despite long time spent next to the CNC machine. However, the experience was invaluable, teaching me the nuances of working with such intricate machinery. Also I am really happy how the coaster turned out and I will be using it in my daily life as well.

Cost Analysis

Cost Type		Price	Source	Quantity	Total
Materials	Sand Paper	6,98 (4 Pc)	Homedepot	1 Sheet	1,75
	Rejunevating Oil	8,98 (1 Pint, 473 ml)	Homedepot	50 ml	0,95
	Softwood	13,32 (1″*12″*4 ft)	Homedepot	1″*5″*10″	3,33
Labor	Prototyping Eng.	53.93 / h	Zippia	1 h	53,93
Utilities	Laser Engraving Machine	40 / h	Woodland	1 h	40
	CNC	35 / h	RouteSpace	3 h	105
					99,95