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- Sand inside of tube by hand with 60-grit sandpaper (this took a long time: next time use a flapper wheel, 60-grit).
- Periodically see it if fits over the motor case. If not, repeat step 1.
- Once it finally fits, sand with 220-grit sandpaper to give it a smoother finish.
- Now it's time for the tube layup. Prepare the layup jig (make sure it's stable, put a pole over it and wrap it with Mylar so that once you start the tube layup, the tube doesn't stick to it)
Carbon fiber is difficult to work with because it snags and frays easily, so make sure whatever surface you're using is completely cleared off. Also make sure that this surface is large enough for the entire piece of carbon fiber, because the fiber will warp if it overhangs.
Length (in) Length + Offset (in) Outer diameter (OD) of tube Circumference of phenolic tube (OD x π) Length of phenolic tube Cut out a (INSERT DIMENSIONS) piece of carbon fiber. This was determined using the table above.
Tube layup: 3 layers of carbon fiber (cut piece slightly longer than necessary for some wiggle room), did not oven cure because of time constraints and whole thing oven cured in the end.
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- MIX EPOXX, DO LAYUP, LET CURE FOR 24 HOURS
-Used Systems 3000 epoxy but didn't oven cure after layup
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| Layer Size | Dry mass of one layer |
|---|---|
| 1 (smallest cutout size) | 20g |
| 2 | 22g |
| 3 | 23g |
| 4 | 26g |
| 5 | 33g |
| 6 (largest) | 39g |
| Total mass of all cutouts (6 sizes x 4) | 652g |
For the tip-to-tip layup, we used a total of 6 boats of epoxy. Each boat weighed (INSERT MASS), not including the mass of the epoxy boat itself, so the total mass of epoxy used was (INSERT MASS).
6. Vacuum Bagging
Vacuum bag was 32 x 38" (this is TOO BIG, make smaller next time. For the test fin can though the bagging was too SMALL, so find a good middle ground)
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