Mast base laminate concerns

[Craig_Hastie]

Hi, I would like some opinions regarding the proposed mast base laminates for a 40' cat. I am quite comfortable with the existing plan from the designer, however, I have had several builders involved with the project question the integrity of the design, and given that the designer has already made several glaring errors, although not in my opinion critical, in this particular vicinity I would like to put the matter to bed once and for all. If I need to beef up the laminates then fine, no big problem, but I would like to do them with purpose rather than intensify the problem. I have not posted much to this site so I am assuming that the jpeg digi's I am about to attach are going to appear with sufficient detail, if not I will try to rectify. My/the builders concerns are the laminates, or more to the point, lack of them, below the post. Further specs available if required.

Regards
Craig Hastie

[Eric Sponberg]

Craig,

If you have doubts about the structure, you should hire a naval architect to review the plans and engineering in detail rather than seek advice from the website. The mast step on a catamaran is a particularly highly loaded structure, and there is not enough detail shown for anyone to make an educated review. In general, the value of engineering advice you receive is directly proportional to the amount you pay for it, excluding the extremes of the spectrum, of course. Good luck.

[Craig_Hastie]

Thanks Eric, The plans have already been passed for Australian survey standards by a Naval architect. However, the designer has chopped and changed the design somewhat since, and whilst I could pay for a Naval architect to review the plans, it has been my experience that the minute I mention the name of the designer, who is also a Naval Architect, I am met with an all too quick response of well I'm sure that ***** has done his best" here is your approval. You have to understand that Australia is quite different from the rest of the world, it is a very small society, one where ones previous work/stature is more important than actual detail. If you take a close look at the pictures you will detect some errors. The composites company that supplied the raw materials for the boats construction, are themselves concerned by the designer in question, their tech support guy, a master builder, has himself voiced concern over the ambiguity and errors in the plans. Don't get me wrong, on the whole we are happy with the design, and are not looking for legal ammunition (note that I blotched out the designers name) as I really don't have the time nor inclination to bother with pursuing the issue in a legal forum. I just want non emotional/biased input. I did not provide a great deal of detail, as I figured that should anybody of some standing respond I could provide it for due consideration. I just want a recommendation as to what could be done to enhance or improve upon the area in question. It's a long story as to why the designers cred is being questioned, and not really relevant in this forum, so I thought I would put it out to the jury. If some work is required to ammend the design then I am happy to pay, problem is that locally no one wants to second guess their "mate".

Regards
Craig

[Eric Sponberg]

Craig,

That is what I meant about seeking another designer/naval architect. If the details are questionable, then you need someone to sort it out. From the information you have provided, there is not enough there for an engineer worth his salt to give any advice. More details are necessary, and they should be handled privately, not on a public bulletin board.

As for "reputable designers"--a designer's/naval architect's work is only as good as the detail he/she provides. If there are structural details that are questionable or not filled in, then what good is the design--and what good is the designer--if the boat can be built? This is not to say that we designers have to provide every last little detail to get the boat designed, but we have to provide a reasonable degree of detail, particularly for special features such as this mast installation on a catamaran, a very highly loaded and important part, so that the design can be built reliably. And if the detail is questionable, then the owner has the right to address questions back to the designer for a clarification. Maybe it will cost a little more money to get the detail you need from the original designer, or maybe you feel safer going to another designer for a second opinion. Either way, pride of reputation should not stand in the way of doing a good job.

Perhaps the problem is more prevalent in the land of OZ, and I am sure we have some of the same here. In my opinion, the goal of boat design (as in practically all fields) is to do a good job at a reasonable price. And if the client is not satisfied, then make sure he has the information to be satisfied. And if the client wants to call in another naval architect, then that is fine, and it is up to the original designer to listen to what the other designer has to say. They should work it out between them. Isolated pride of reputation gets you nowhere. Yet, if the designer works to keep his client satisfied and provides the detail needed, his reputation will be more enhanced because he can work the problem through.

I have pontificated long enough. Best of luck.

Eric