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- A respirator is required for all steps involving sanding fine particles like carbon fiber and phenolic
- A respirator is required when using colloidal silica before it is completely mixed into the epoxy. The respirator can be taken off once the silica is completely mixed UNLESS the epoxy you are mixing it into also requires a respirator.
- A respirator is required when using West Systems 3000 epoxy
- Gloves are required when sanding carbon fiber to prevent small splinters
- When using the Dremel, use safety goggles that completely cover your eyes to protect from stray projectiles
- Use safety goggles that completely cover your eyes when sanding so that fine particles do not irritate them
Here is a summary of the procedure, including the approximate time that each step took.
| Design fin can | Approx. Time Required | Number of People Required | Notes |
| Fin Design & Manufacturing | 36 hours | The more the merrier. | Manufacturing procedure and detailed breakdown described in "Hermes 2 Fin Design & Manufacturing" |
Design/make jigs | |||
| Root bond jig | |||
| Fillet jig | |||
Tube preparation | |||
| Sand tube | |||
| Tube layup | |||
| Root bond | |||
| Root fillets | |||
Layup preparation | |||
| Lasercut cutouts | |||
| Spray-glue to wax paper | |||
| Sand fillets | |||
| Prep vacuum materials | |||
| Layup | |||
| Wet plies/weigh | |||
| Layup | |||
| Apply vacuum bag materials | |||
| Vacuuming | |||
| Oven Cure | |||
Set up oven/vacuum materials | |||
| System 3000 cure cycle | |||
| Remove vacuum materials | |||
Clean up edges (Dremel/sand) | |||
| Static load test | |||
| Design/build jig | |||
| Determine testing loads | |||
| Static load test | |||
| Analyze data | |||
| Post-processing | |||
| Sand fillets/outside | |||
| Outer fillets on low spots | |||
| Paint |
1. Tube Preparation
The fin can fits over the motor case (at least, it's supposed to...). Since it didn't quite fit, we sanded the phenolic tube using a flapper wheel, and then overwrapped it with 3 plies of carbon fiber. The phenolic tube acts as insulation from the heat of the motor case and is not structural, so carbon fiber needed to be added to bear the structural loads. During the tube layup, the phenolic tube was held by a pole over the layup jig (much like a pig on a spit). Have at least three people helping with the tube layup.
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