For our final homework assignment of the semester, we had the opportunity to use a CNC machine to make a noun of our choice! Initially, I was deciding between making  a coffee mug or a tree; however, after messing around with both for a bit on Carbide Create, I found that the coffee mug shape seemed to be much more challenging to CNC while maintaining its shape, so I ended up going with the tree. I also added a circular outline with a flat bottom around the tree so that I could use it as a decoration on a shelf or desk.

 ecause I wasn’t going to be able to work on the assignment over the weekend due to a trip to Dallas, I decided to get an early start! As soon as I’d received my training on how to use the machine, I booked a time and got to work creating my object. First, I picked out two nice-looking blocks of wood. Then I set everything up by securing my wood, zeroing the machine, making sure I had the right tool in, and hitting “start!” 

The whole shape took about 15 minutes to cut out, and everything generally went very smoothly. The only issue was that, despite me measuring the wood in multiple please, the piece I used was quite warped and didn’t cut all the way through everywhere. However, the layer of wood left was thin enough that I was able to use a tool to punch it out, and then sand down the edges to smooth everything out. I ran into slightly more trouble on my second piece, which I didn’t measure as carefully. The machine once again didn’t fully cut through the wood, but this time enough was left that I couldn’t manually fix it. I decided to re-tape my piece, re-zero the machine, and cut just the outside path that hadn’t gone all the way through, this time adjusting the thickness more accurately. This seemed to fix the problem, and the piece turned out great.

Finally, I finished my shapes by painting the insides of the leaves and trunk with acrylic paint in fall colors. After the first coat of paint, I wasn’t totally satisfied with how it looked due to the roughness on the edges and insides of my leaves, so I ended up sanding them down a bit with some sandpaper. I also lightly sanded the surface of my wood. Then, I applied a second coat of acrylic paint and sprayed my piece with a clear coat. 

Overall, I was very pleased with my piece. If I could change anything, I think I would’ve sanded it better. In addition, it felt very rough after applying the clear coat, so I think I would’ve potentially stained it or chosen an alternative finishing option if I could do it again.

Cost Analysis:

Cost Type	Cost	Price	Source	Quantity	Total
Materials	Wood	$2.28 for 3.5” x ⅝ x 6’	Lowe’s	2 pieces: 3.5” x ⅝” x 6.75”	$0.43
	Acrylic Paint	$5.99 for all	Michael’s	~ 1/12 of paint	$0.50
	Clear Coat	$6.19/12 oz	Amazon	1/12 of can	$0.52
Labor	CNC Machining	$21/hr	ZipRecruiter	1.5 hours	$31.50
	Painting	$21.87/hr	ZipRecruiter	.5 hours	$10.94
Overhead	Facility Cost (Machine Time)	Assume 15% of labor and materials	Rockler	N/A	$9.82
	Quality Control	Minimal time spent	N/A	N/A	$0
Design	Engineering and Development	$43.12/hr	ZipRecruiter	30 min	$21.56
Total	$75.27