Alpha 42 "Be Good Too" rescue 300 miles off Cape Henry Merged

[Boatguy30]

There was a blog post I guess sent prior to the damage of how comfortable they were while lying to. I think it was by the dealer as it noted the wide beam high bridgedeck clearance, etc.

I would imagine the motion must have been quite bad with no steerage. Of course at this point they need to justify the abandonment to the insurers.

[rickbase1]

I decided to go with a Balance 451(14 metres or 44 ft) and my shafts are solid stainless, approx 48mm, which is just shy of 2 inches. The initial travel limits are set to 30% and the load calculations were done based on a working load of 12 knots at full turn. The stocks are easily accessible from a top hatch (where the emergency manual tiller fits over the stock) so they can be hammered out from the top in an emergency.

Hopefully I won't find myself in a similar position as the unfortunate crew of the Alpha 42, but if I do many of the productive comments in this thread will help in ensuring that I will overcome it.

[Cotemar]

Originally Posted by rickbase1

I decided to go with a Balance 451(14 metres or 44 ft) and my shafts are solid stainless, approx 48mm, which is just shy of 2 inches. The initial travel limits are set to 30% and the load calculations were done based on a working load of 12 knots at full turn. The stocks are easily accessible from a top hatch (where the emergency manual tiller fits over the stock) so they can be hammered out from the top in an emergency.

Hopefully I won't find myself in a similar position as the unfortunate crew of the Alpha 42, but if I do many of the productive comments in this thread will help in ensuring that I will overcome it.

You did not stray too far from the tomahawk bows, did you.

Balance 451 will be a nice ride.
It has a bit more background, but still a new design.

What hull # will you be with the Balance 451 ?

[chris in SG]

Originally Posted by Boatguy30

It sure looked to be tube in the pic he posted. The "substantial" end stops looked to be easy to shear as well. But likely the rudders will be long gone prior to that.
.

Come on guys, HE is a member, albeit a newish one and he has a name, which is pretty obvious. And, hello, HE has already answered the same question.

Hardly the way to make new members feel welcome..

(Oh, by the way, thanks to GordMay for the welcoming post!)

[malbert73]

Originally Posted by DotDun

I didn't make myself clear. The reason a 1.5" shaft fits the requirement for normal usage is the small amount of space. I don't believe spade rudders are design for high speed reverse. When that happens, all bets are off.

No rudder is designed for high speed reverse, spade, skeg or keel attached. I just don't think designers are over-engineering rudders sufficiently these days. I would prefer that my rudders survive a thrashing that makes me need to abandon ship for a different reason. All it would have taken in this situation or similar is a stronger internal web bonded to bigger rudder posts, like 3 inch perhaps, coupled with solid rudder stops. Yes, they can always still fail, but it should only be from contact with something solid except in truly exceptional conditions, which these were not.

For those that say this is impossible- I am not a naval architect, but think there is no reason spade rudders for monos and multis can't be overbuilt enough to make failure from anything other than ground contact extremely unlikely. like I said earlier in a post, priorities for designing offshore cruising boat should be 1. Keep water out, 2. Maintain steerage, and 3. Keep rig up.

But yes, I also grant the point that this was a timetable driven trip and shouldn't have been undertaken with a new unproven design.

For all of us who insure our boats, this is yet another example of poor design and poor decision making that will cause all of our rates to go up over time.

[boatman61]

Originally Posted by chris in SG

Come on guys, HE is a member, albeit a newish one and he has a name, which is pretty obvious. And, hello, HE has already answered the same question.

Hardly the way to make new members feel welcome..

(Oh, by the way, thanks to GordMay for the welcoming post!)

Nice one He...
Welcome to CF Chris...

[Doe818]

Anything drawn by roger hill will be a very strong and robust boat if built anything close to his usual spec, which I'm sure it has been. You will be muuuuuch happier in one of roger's boats than this other thing.

[Doe818]

talking to rickbase of course

[Boatguy30]

48mm just happens to be 1.5" pipe OD. Odd size for solid bar. Good luck!

I'm using Sch 160 1.5" pipe on a 34' cat.

[sigmasailor]

Good point! (Nominal Pipe Size - Wikipedia, the free encyclopedia).
You're quite right; in Europe (larger) bar stock often comes in even mm increments; I guess in the US per 1/8 of an inch or similar.

The really fun part is that a decent sized pipe (sch 160 and up) is almost as strong as bar stock of the same diameter. That's why carbon works so well; it is very strong and you can put the fibers at work where they count (on the outside).

[rickbase1]

For those interested I have started a new thread with an overview of my electrical and mechanical design decisions and how I plan to have aircon without a genset. Productive insight is always welcome.

Hopefully this link works but if not search on "Aircon without a genset?"

Aircon without a Genset? - Cruisers & Sailing Forums

[minaret]

Originally Posted by sigmasailor

Good point! (Nominal Pipe Size - Wikipedia, the free encyclopedia).
You're quite right; in Europe (larger) bar stock often comes in even mm increments; I guess in the US per 1/8 of an inch or similar.

The really fun part is that a decent sized pipe (sch 160 and up) is almost as strong as bar stock of the same diameter. That's why carbon works so well; it is very strong and you can put the fibers at work where they count (on the outside).

Sure, but you can't keyway a pipe, let alone double keyway it. A bolt is just silly.

[sigmasailor]

Ah, didn't really think of that.

If you would take an XXS 3 inch pipe you would have .6 of an inch (15+ mm) to work with. It would still be a little lighter (looked it up) than 38 mm bar stock.

[minaret]

Originally Posted by sigmasailor

Ah, didn't really think of that.

If you would take an XXS 3 inch pipe you would have .6 of an inch (15+ mm) to work with. It would still be a little lighter (looked it up) than 38 mm bar stock.

How many lbs lighter? This attitude is the source of the problem. Shaving off a couple of pounds is not worth having a boat with no structural margin of error. Saw your toothbrushes in half before reducing the size of your steering gear. All this effort, expense, and compromise to build a super light weight boat, and you know they are just going to fill it with cases of wine if they are going cruising...



Were you suggesting cutting a 1/4" keyway into the .6 wall thickness of the pipe? Not sure that would be wise...

[Sand crab]

All this talk about tube and pipe needs just a little explaining for those unfamiliar. Pipe size is usually specified as the inside diameter of the pipe. The wall size can vary which will give you different outside (OD) dimension. Tube is usually specified as an outside dimension only. A "solid tube" is called round bar and is the size specified.
These rules do have exceptions.