- PC Composites, Machine Sciences, and Boeing have showed interest in
- Trapezoidal fins with a large sweep angle (70 degrees from
perpendicular) show a slight advantage over other fin types, based on some
preliminary OpenRocket testing.
PSAS meeting notes
- *Getting a freezer for the CF is our immediate bottleneck.* LV4 is in
charge of this, but there's no reason LV3 can't help.
- See Boeing notes about sizes.
- There are walk-in freezers in the SRTC. I'll ask about them.
- We should ask Machine Sciences if they would be willing to do the
machining for the NSR too. (After the stuff for LV3 of course.)
- Does the CF need so be stored in an inert atmosphere?
- No, according to Sandie, our Boeing contact, it just needs to be
vacuum bagged to block moisture and kept in a freezer.
- If we're worried about heating in the nose cone, we should look up
what temperature epoxy starts to be damaged at.
- N-class motors are essentially our design motors.
- During the PSAS meeting next week there will be a short introduction
to Github... in theory.
- Open question for the whole airframe mailing list and LV3: *what
stability margin caliber is too low?*
- Stability margin caliber is how far the center of pressure (CP) is
behind the center of gravity (CG) in units of rocket diameters.
Boeing meeting notes
- The Boeing CF comes in widths ranging from 6" to 60". They have 24"
wide rolls, which would be ideal. (The PCC rolls are 5 feet?)
- If Boeing donates material it will be 8276 (unidirectional) and
- "Cat 1" or "Category 1" material is super-primo aerospace grade.
- "Cat 3" or "Category 3" material is no longer fit for making
planes, but still pretty great.
- The prepreg they use isn't tacky at room temperature.
- They use tackifier (basically adhesive) to get it to stick to
things. Heating it might also work.
- They might not have any adhesive sheets to donate, since that's not
a thing they really use.
- *We need to make a list of the things we want from them, including
- The way material donations from Boeing work is this... They keep a
bunch of stock. Sometimes some of it goes unused and expires. Sometimes
they order a lot of stuff and their freezers get full. When this stuff
happens, they normally just pass it on to the University of Washington.
- Because we're not part of this default donation process, we need to
periodically ask if there's going to be a donation cycle soon. Leslie has
volunteered to do this.
- There *might* be future seminars on CF, composites, and material
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