Manufacturing Projects
Manufacturing Projects
Embedded Files
Turner's Cube
The CAD and Final product of my Turner's Cube
This shows all of the toolpaths needed for this project. I created four separate setups, two of which must be used twice.
As the head of the CNC shop, I am in charge of designing the trainings for the tormach mills and lathe. This is the training piece for the CAM mill training, a Turner's Cube. Turner's Cube's are a classic CNC practice piece. They are great for learning because it has multiple set ups, but you can design the toolpaths around the center of the part to avoid tricky rotations. In addition the final piece is delicate, so you have to be careful with how aggressive your feeds and speeds are. During this project, I calculated baseline feeds and speeds for every tool in our library based on the horsepower of our machines and the desired chip load per tooth for use by everyone in the shop.
Treasure Box
This project was my introduction to design for manufacturing concepts. In particular, maximizing material removal rate based on the tools and machines available, keeping tolerances to specifications, and minimizing machining time and tool changes.
To up the aesthetics I chose to powder-coat the final box in a sparkly black. Then I ran an engrave pass which revealed the metal beneath in the shape of a dog bone. To keep the tolerances on the pin holes, they were not powder-coated.
The hole sizes and locations for this project were critical. The pins were to be press fit into the bottom and needed to slide smoothly without catching in the top. I accomplished this by carefully calculating the necessary hole sizes based on the drawing of the pins. I chose a class V locational interference fit for the press fits and a class III medium fit for the sliding holes. My press fit calculations for the diamond pin (top) and dowel pin (bottom) are shown to the right.
Teacup Plant Pot with Saucer
As one of my first forays into design for manufacturing, I designed and created a urethane succulent pot in the shape of a teacup complete with a water-catching saucer.
The goal was to create a two part silicone mold for the teacup, and a vacuum forming negative for the saucer. For the silicone mold, the handle was a particular challenge. For a two part mold, the parting line had to be down the spine of the handle so it could be demolded, but that created a large overhang inside the cup. Silicone is flexible, but as I was using tin cure silicone, ripping was a consideration. I mitigated this risk by making the walls of the silicone mold thinner all the way into the cup, making it more flexible.
After designing the shape of my cup, I created a structure for my silicone pour including walls, vents, and the thinning nub. I carefully put my vents everywhere bubbles could get stuck during the urethane pouring, focusing on the handle. I then poured the silicone in two phases, using a generous amount of mold release between the two pours.
This is the blank I used for vacuum forming. It has tiny holes throughout to aid in suction, preventing any areas from getting sealed off before they are fully formed. Additionally, it has a slight lip around the rim to aid in cutting it out. This shape is particularly well suited for vacuum thermoforming, therefore I did not have to make considerations for ribbing or snapping. I printed this in ABS because when I tried it with PLA, the heat from the thermoformer warped the blank.
Mold and blank making took far more materials and time than creation of the cup and saucer. Based on material and time cost estimations, I calculated the cost of a single cup and saucer including the cost of mold production, based on how many cups were produced. As more cups are produced, the mold cost is distributed more. This is assuming all of the cups can be produced with a single mold, however I ended up being able to make nine cups before the mold began to degrade.
Injection Molded Spork
Continuing in my mission of mass production, I created a metal mold which can be used to injection mold sporks.
The goal of this project was to make an aluminum mold which could be used repeatedly to mass produce travel-sized sporks. The design features a hole for a key chain, times for stabbing, and a small depression for liquids. I used black and white abs mixed together to achieve a marbled look.
I designed a two-part mold. One half contains the cold slug well, runners, gates, and vents (scratched in) alongside the main body of the spork. The top half contains the sprue and two nubs which form the indent in the spork.
To the left is the design of everything that is injection molded. When my mold is used, this is what is created and the sporks are later separated and cleaned up. I used this model to perform several analyses to ensure it would be able to be molded and demolded. Additionally, this model was used to determine how much plastic must be used to produce each spork.
Below is the cost analysis of a single spork. It takes very little time and material to produce a single spork, however the mold making and other upfront costs are very high. As more sporks are created, the up front cost is distributed across more products, resulting in a lower per spork price.
Page updated
Google Sites
Report abuse