Thanks so much for the great perspectives, this is extremely helpful.
No doubt who does the extension is critical but it can be done with excellent results. There's also the added benefit of increasing hull speed so if the boat's run like most of these old MYs he now can run a little bit faster.
Saltshaker, great point. A 6' extension is approaching 10% of the waterline. If I understand the formula correctly, it would be the difference between a hull speed of about 9.6 kts vs 10.1 kts. In reality, our sweet spot seems to be closer to 9 kts (12 total gph on 8v71's), but I would love to see anything approaching half a knot improvement. At that rate it would only take about 10,000 hours for the cockpit to pay for itself in fuel savings
It's usually better financially to let someone else do the extension. They spend the 200k and you buy the boat for about 20 over a standard one. Better than that is a factory model with a cockpit and all the correct running gear. As far as the transition to a new vessel. It's not the end of the world. It could be though of as a positive.
Scott, I couldn't agree more that it is economically better to let PO's bear the burden of upgrade expense. The PO in my case had $600K invested, and we acquired her for less than $200K. However, if I go shop for CPMY, I don't think it is possible to come close to this differential.
Jerry/Joy Sea yours is a good argument for going ahead with the extension. You may find what you want out there but if you end up having to spend the same money on other upgrades, it may not make sense. I'd stick with what you have and spend the money on the extension. I'll second what Cricket said earlier, none of this makes sense from a pure financial perspective but spending money on boats never does. If you plan to keep her for a long time and are OK with the expense, then go for it. You'll still be way ahead of the game than if you bought a new boat.
Thanks again Saltshaker. We do love Sea Joy (and I acknowledge part of it is emotional) and are VERY satisfied with what she is and what she can do (ok, other than the lack of cockpit). I really don't want a bigger boat, just the increased utility of the cockpit. Like you and Cricket say, if we really did the math we never would have bought a boat. Of course I was into airplanes before, so boats actually look pretty pragmatic in comparison. The admiral thinks we are saving tons of money
and maybe we are!?
If you love the boat and are not concerned with the expense of adding the cockpit don't let the sea keeping capability of the project stop you. Many many Hatteras Motor Yachts have been extended and they're cruising around just fine. I've run many of them, and if done right you can't tell the difference from a factory boat unless it's out of the water and they didn't extend the shafts, wheels and rudders, which MOST Didn't. A very common Hatteras model that was extended was the 65MY making it a 74CPMY. Also I believe it was the 72MY making it an 80CPMY. Again of done properly you can't tell the difference from looking at it dockside and the handling doesn't change much either. The only time I ever noticed even a slight difference was maybe on a big following sea from the 1/4, and lets face it NONE of these old top heavy slow Motor Yachts exactly perform great in that condition. It's noticeable, but nothing that is unsafe or that a good autopilot can't keep up with. Just so I'm clear, I'm not even 100% sure it's worse at all over a standard factory Hatteras MY/CPMY because non handle great in those conditions. Just pick a good yard. I know Allied Marine on the New River use to do a ton of them and had their own mold but that yard has since closed down years ago. I'm not even sure who to ask now, other then maybe Slane?
Tony
Thank you capttonyf - some more great perspective. As I said above, we absolutely love this boat, and living aboard. So much so, we are selling our remaining "dirt" and aspire to be full time cruisers. Anyway VERY good point about the molds. I will start asking yards specifically about these. Seems like that would make a huge difference. I have reached out to a couple of yards based on suggestions on this site (Composites in MD, American Custom Yachts in Stuart, etc). I had not reached out to Slane, but will do so tomorrow! I believe a yard in St. Augustine did Bruce's 54 that was a topic on this same thread, but I need to track down the name.
BTW, we had trailing 4 footers on the 1/4 coming back from Key West a couple of weeks ago and if not for the stabilizers we would have inadvertently rearranged all of the furniture in the salon. The Simrad AP28 handled it better than I could.
