interested if anyone has any opinions on the following:
1. Is there any specific disadvantage, other than price and possibly environmental considerations in manufacturing, of an epoxy hull compared to a poly/vinyl-ester hull? (comparing apples to apples - i.e. assuming both cored with same core material)
Epoxy is subject to thermal distortion at lower temperatures than poly/vinyester resins, so in the case of most epoxy-composite boats, dark colors are best avoided. However, the will generally be more resistant to osmosis, stronger, and a bit lighter.
2. (I know this has been discussed somewhat previously & have looked at the posts) what disadvantages are there to lead versus iron keels.
Lead is more expensive and more toxic. However, it has a higher density and as such will have less wetted surface area for the same righting moment (weight in ballast). It is also far more forgiving in a collision, with an externally mounted keel, since the lead tends to deform and absorb a lot of the impact energy, rather than transfer it to the keel support structure.
i ask just because as i look around for next boatie, it seems to me that apart from (relatively) small price differences, there are no disadvantages to epoxy hull and lead keel. i do see some disadvantages to carbon fiber spars.
would be interested in others' thoughts.
Carbon fiber spars have a few major disadvantages, especially for a cruising boat in remote regions. First, it isn't as easily repaired, requiring fairly sophisticated materials and techniques to repair it. Second, in a lightning strike, a carbon fiber spar may look fine, but actually have serious delaminated areas and be a serious danger to the boat. Third, there are some serious galvanic corrosion issues with hardware attachment to a carbon fiber spar, given carbon fiber (graphite) relatively high position on the anodic scale.