plasticfactory
Champion
This project is finally wrapped up and posted with permission from the customer, @JasenHicks. It is an injection molded cap for use on Cherry MX switches in his brilliant new fight sticks. I highly recommend that anyone looking for a stick check out his new products.
As the entire thing still wound up being a bit of a labor of love, I thought sharing some broad strokes of what this process can look like may be interesting to some users here. Though the part design is simple, it posed some unique, unexpected problems that were fun to solve.
The attached timeline and photos definitely leave some things out, as I didn't initially plan on sharing this, but they cover most of the major steps.
Part and Mold design:
First, we start with the part design, provided by Jasen, followed by a feasibility study, then the mold design. In this case, we used what's called a "MUD" base system for use in a vertical injection molding machine. This results in a very compact mold, a very small runner, and rapid changeover. Essentially, you simply remove two toe clamps from the top of a mold base that lives in the machine, and slide the mold out. It's an excellent system for small or simple parts. It falls out of favor when the parts become more complex or require larger mold systems and special actions.
In this case, because there are two part sizes, a MUD base was perfect as we can do both parts in one mold. When the large cap is finished running, we simply remove the toe clamps and flip it 180*.
Mold Build:
Once the mold is designed and a job folder created, we build the mold. The steps are approximately as follows (photos follow in order):
Another really cool thing about EDM machining, is that it doesn't care about material hardness. This mold is ~50 HRC.
Now, it's time to sample! Fingers crossed the parts look good, right?
As the entire thing still wound up being a bit of a labor of love, I thought sharing some broad strokes of what this process can look like may be interesting to some users here. Though the part design is simple, it posed some unique, unexpected problems that were fun to solve.
The attached timeline and photos definitely leave some things out, as I didn't initially plan on sharing this, but they cover most of the major steps.
Part and Mold design:
First, we start with the part design, provided by Jasen, followed by a feasibility study, then the mold design. In this case, we used what's called a "MUD" base system for use in a vertical injection molding machine. This results in a very compact mold, a very small runner, and rapid changeover. Essentially, you simply remove two toe clamps from the top of a mold base that lives in the machine, and slide the mold out. It's an excellent system for small or simple parts. It falls out of favor when the parts become more complex or require larger mold systems and special actions.
In this case, because there are two part sizes, a MUD base was perfect as we can do both parts in one mold. When the large cap is finished running, we simply remove the toe clamps and flip it 180*.
Mold Build:
Once the mold is designed and a job folder created, we build the mold. The steps are approximately as follows (photos follow in order):
- Square Stock (no photo)
- Rough cut the cavity blocks, finish cutting back plates and knockout system components
- Machine the EDM Electrodes
- EDM machine everything to size (can I attach a video?)
- WEDM Knockout holes (no photo)
- Polish the mold for a gloss surface finish on the parts
- Final fitment, mold venting
Another really cool thing about EDM machining, is that it doesn't care about material hardness. This mold is ~50 HRC.
Now, it's time to sample! Fingers crossed the parts look good, right?
Last edited:
It was a fun project -- now for colors!
