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| Approx. Time | Notes | |
|---|---|---|
| Design fins | 10 hours | We used the design from Hermes 1. Next time, we should do more detailed analysis. |
| Total design time | TBD | |
| Waterjet G10 | 3 hours | Make sure it doesn't delaminate by leading in to the cut |
| Waterjet phenolic | 3 hours | Make sure to weight down the part because it's long and thin and moves around. |
| Cut G10 tab | 4 hours | It's going to be difficult to get this accurate because sheet stock has a variable thickness. |
| Cut phenolic slot | 4 hours | Use machine oil or it'll get spicy. |
| Phenolic taper | 4 hours | Used 15-degree taper for Hermes 2. Taper may need to change for future designs. |
| Mill down phenolic | 2 hours | May or may not need to do this depending on the total thickness of CF on each side of the fin |
| Assemble fins | 2 hours | Don't use 5-minute epoxy. |
| Bevel fins | 4 hours | Did this by hand- could make a jig to get a better result and save time. |
| Total manufacturing time | 26 hours | The more you do it, the better you get, but allow for set-up and things going wrong. |
Things to improve for next time:
- Make a jig to bevel the fins or figure out some better way of doing it than by hand
- Consider using honeycomb for the fins- would save mass while maintaining strength
Test Fin Can Fins
Below is a picture of the fins used for the test fin can layup. These dimensions were obtained from our OpenRocket sim, but were not the updated shape of the fins. This was acceptable for the test fin can layup, but for the flight candidate layup the shape was different.
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Talk about design of phenolic slot (0.3" deep, 1/16" thick)
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Flight Candidate Fin Manufacturing Process
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