We have learned over the years how to rub the world the wrong way and get away with it. This manifests itself in many ways. In the case of the Wicked FPB 97
it takes the form of this massive extrusion which surrounds the hull to deck intersection. This is 8mm (5/16″) thick on the sides and a full 12mm (1/2″) on the outer edge. If you want to lay on pilings without fenders in a sub-optimal harbor, this belting/rub rail, is what you want. A scaled down version of this is used on the FPB 64s and FPB 83 .
As a hull to deck reinforcement it will also pay dividends in a collision, when you are the impactee instead of the impactor (another of those lessons learned the hard way).
Custom extrusions like this are costly, not easy to shape to the hull, and in general a pain to work with on the shop floor. They also add weight up high which we give up begrudgingly. But they make us feel warm and fuzzy, secure, knowing that we have the toughest belting on the block – or maybe the entire planet.
Posted by Steve Dashew (January 19, 2013)
January 27th, 2013 at 12:14 pm
Does scaled down mean the same extrusion on a bigger boat, or is the rail even beefier on the 64 / 83’s? Did you have a die made for this extrusion?
And, I would have to agree that it is the toughest on the planet.
January 28th, 2013 at 11:49 am
Separate dies are used for each extrusion. The belting for the 64/83, massive in its own right, is about a 1/3rd smaller/thinner than the 97s.
January 28th, 2013 at 3:34 am
How do you bend this round the topsides?
January 28th, 2013 at 11:48 am
With great difficult. It is what separates the men from the boys in this business.
February 3rd, 2013 at 1:46 am
I should imagine that warming it up helps
February 3rd, 2013 at 12:48 pm
Heating not required.
January 29th, 2013 at 2:06 am
If you were producing this craft in bulk, it would make sense to make molds and press ~10′ sections. That would also make repairing damage easier.
January 29th, 2013 at 9:01 am
I doubt we will ever have to worry about replacing a section of this belting, unless t-boned by a large ship, in which cases there will be other, more pressing issues (pun intended). I suspect it might take a large production run to amortized the 20 molds (no straight lines here!), and too many of the same would be boring. So, you can be sure we will stop building 97s by before that occurs.
January 29th, 2013 at 1:14 pm
I would knock up a set of vertical rolls with bosses on the lefthand roll to stop the extrusion spreading whilst rolling is in progress and a corresponding indent in the two righthand rolls two keep the centreline true. The alloy might need to be annealed; rolling it would put the hardness back.
Jonathan.