For our midterm project we are tasked to draw and assemble a simple wood machine taken from a woodshop book. We are to use 2D vector drawing, laser cutters, plasma cutters, and post-processing techniques.

For my project, I will be making a simple gear machine which I created a vector drawing of previously.

Low fid and 2D Drawings: 

For the first part of the midterm project we were tasked to update our 2D drawings and create a low fidelity prototype.

For my 2D drawing, I played around with the handles and gear teeth. The handle I added some pieces so it would be more 3D and handle like and the gear teeth I adjusted in height so it would line up better. I also realized that some parts would have to be cut several times in order to be the appropriate thickness for the final machine.

Below are the updated AI files

cogMidterm

bottomMidterm

Wheel-1nt6dmn

Furthermore, I constructed a low fidelity prototype to get an idea of how the spacing would work between the moving pieces and how to line the teeth up properly

Continuing with the project: 

Next I took the modified files and created my first laser cut edition. It became obvious that there were several issues with this edition.

1. The holes in the bottom section were too large for the 1/4 inch dowel
2. The handle for turning the top cog was too low, a second wood “washer” piece was needed to raise the handle so it wouldn’t hit the bottom cog and get stuck
3. The number of pieces I printed for the bottom wasn’t sufficient to fill the base rectangle so the teeth section on the bottom slid front and back also instead of just left and right
4. The cog teeth get a little stuck with each other
5. The teeth on the bottom piece are too far apart

To fix these problems I went back into the design and changed the holes on the bottom pieces to be 1/4 inch diameter to fit the dowel, printed a second  “washer piece”, and decreased the width of the base by 1/4 inch. I also decreased the length of the teeth on the cogs and bottom piece by 1/8 inch and spaced the bottom teeth closer (13 instead of 11).

Working on the final product: 

For the final product I took the technical changes and also added an aesthetic change. Instead of having the original pattern given in the wood shop guide book, I found a planetary image and set it to be engraved into the top piece of the back section.

I modified the image in photoshop to get rid of as much gray-scaling as  I could to make it easier to engrave, below is a downloadable photoshop file

backgraphics (photoshop file)

Afterwards, the image was processed with Live Trace in the illustrator application with the black and white logo setting. Then I deleted the white shapes to prevent the laser cutter from going over each shape twice.

(Each piece was cut on 3-ply plywood)

BackWheelMidterm (Engraved back piece, cut 1x)

Cogmidterms2 (Cog pieces, cut each piece twice except the handle piece)

BottomMidterm3 (Bottom section, cut 3x teeth pieces, 11x pieces of the thin rectangles with the circular center, 1x piece of the large rectangle)

GlueOnBackWheelMidterm (Cut 3x)

Once the pieces were cut I began assembly:

1. Glue 3 of the thin rectangle pieces together, make sure the holes line up
2. Glue the other 8 pieces of thin rectangle together, make sure the holes line up
3. Glue the three bottom teeth pieces together
4. Glue the 4 half circle back pieces together, make sure the engraved one is on top
5. Glue the two large cog pieces together
6. Glue the two small cog pieces together, and the two washers stacked up on top of them, then the handle piece on top of that.
7. Allow all the pieces 24 hours to dry
8. Make plugs: measure out one piece of 1/2 inch dowel. The dowel should be long enough to fit through the back half circle and the small cog+washers+handle piece + 1/4 inch left on either side. Mark and cut the dowel to length (example picture below) and mark a dot on each end as flush to the cogs and back as possible. Take a size 1/40 drill bit and drill two small holes where marked (drill press is suggested). Put a toothpick through one end of the plug, cut down to size, and add some glue to hold it in place. Then place the plug through the back piece and the small cog piece. Add a toothpick into other end too to hold all the pieces in place. Repeat with the large cog.
9. For the handle piece, I took a wooden ball of about 3/4 inch diameter and drilled a 1/4 inch hole with a drill press about 1/4 inch down. Then I cut a 1 1/4 inch piece of 1/4 inch dowel, glued one end into the ball and glued the other end into the appropriate handle hole
10. Cut a piece of 1/4 inch dowel the width of the base piece. Insert it into the 3 piece of thing rectangle and glue in place. The end of the dowel should be flush with the front of the 3-rectangle “brick”. Thread the dowel through the teeth piece. Insert the other end of the dowel through the 8 rectangle”brick” piece. Glue the two brick sides to the base (teeth facing up) but make sure no glue gets on the bottom of the teeth piece.
11. Once the bottom section has dried glue the top the back to the 8 rectangle “brick” portion, flat part down, as forward and close to the teeth piece as possible
12. After this step I noticed that the teeth piece stuck a little along the bottom so I smeared some lithium cream along the base and on the sides where the teeth piece rubbed against
13. Lastly, stain the project with some wood stain (I choose linseed oil). Pieces can also be spray painted in between gluing if desired.

For future iterations I would try getting a deeper cut into the engraved section to make it stand out more, the right hand side is woefully shallow and doesn’t show the design well at all. I was also planning on using some 1/2 clear acrylic for the cogs so the design would have stood out more, but didn’t have time to order the material and made do with wood I think it would also have been cool to incorporate some metal pieces into the design but there were a couple problems with that (wood and metal don’t glue well, and you can’t get the plasma cutter to drill holes in the center, though the second issue could be resolved with the drill press possibly).

Overall, the project works and looks pretty decent. Craftship wise, the bottom plug is a little on the unstable side (fixed by putting a piece of masking tape around the dowel to make it slightly thicker) and the bottom teeth didn’t line up perfectly when I glued them together. There’s a lot of creative license with this design since you have a good canvas to work with on the back piece and also a bit in the front too. The cogs can be made of different materials or sprayed different colors too. This time around, I wanted to keep more to the traditional aesthetic and have the focus be on the engraved section in the front. But I think next time I’ll experiment more with different materials.