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Q: How bad is it to machine holes into carbon fiber parts?
A: Although it's better to avoid if possible, it CAN be done if necessary; people do it. Obviously it does weaken the carbon fiber but not necessarily to a point where it's unusable. A "knockdown factor" can be calculated based on the geometry of the hole and of the piece you're machining. I can't give a specific number because it all depends on those parameters, but there are procedures for tests and calculations to be performed that would tell you exactly how much strength you're losing as a result of cutting out pieces of a carbon fiber part. [Asha's comment: we should run some of these tests to quantify how much strength we would lose! But also ideally we just design good so we don't have to drill holes in the first place.]
Q: Is galvanic corrosion a risk for us when we bond aluminum to bonding carbon fiber to aluminum?
A: Not really, especially considering you're competing in a dry desert. It's more of a concern for systems that need to last many years and mostly ones exposed to moisture. Aircrafts for example because they will need to fly through rain.
Q: Should we consider using another non-metal like fiberglass for example?
A: Not unless cost is an issue. Carbon fiber is better all around.
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