hull reinforcement with liner

xact · #1 (**permalink**) 01-29-2010

my boat has a liner and I am looking to reinforce the hull it.
does anyone have experience in this sort of procedure ?

Jeff_H · #2 (**permalink**) 01-29-2010

You do not say precisely what you have in mind but I assume that you are talking about adding internal framing. I do not know of an easy way to reinforce the hull with a hull liner other than to temporarily remove sections of the liner, build up the internal framing that you wish to add, and then glass the liner back in. You may also look at developing as sytem to reinstall the liner in a manner that allows the liner to be removable, or leave the liner out if you are going offshore. (I personally think that liners are dangerous on an offshore boat because they limit access to the hull should you be damaged underway.)

Jeff

xact · #3 (**permalink**) 01-29-2010

Yes I would agree, and yes offshore it is.

If I was to add framing do you think there would be an issue of the framing stiffness effecting the glass structure so as to create flex points in parts of the panels that could compromise the panel strength?
Or are we talking more framing more strength period

mitiempo · #4 (**permalink**) 01-29-2010

Generally a bulkhead has foam between it and the hull so as not to create a hard spot. Framing usually is not as unforgiving as a full bulkhead and isn't stiff enough to create a hard spot if done properly. What kind of boat is it? The more information the better.

boatpoker · #5 (**permalink**) 01-29-2010

Quote:

Originally Posted by mitiempo

Generally a bulkhead has foam between it and the hull so as not to create a hard spot. Framing usually is not as unforgiving as a full bulkhead and isn't stiff enough to create a hard spot if done properly. What kind of boat is it? The more information the better.

What you describe is the proper way to attach a bulkhead however, in over 2000 surveys I have never seen a production boat built this way. Do you know of any ?

xact · #6 (**permalink**) 01-29-2010

its a tanzer 26.
I dont think I would be adding any bulkheads, I was thinking just cemi circle ribs of epoxy/glass, to increase rigidity.
and lengthen some of the semingly short tabbing on the liner.

mitiempo · #7 (**permalink**) 01-29-2010

boatpoker
Not that I've personally seen but maybe Morris? And the two half bulkheads I added to my boat beside the galley stove are done that way. It's easy to do and any kind of foam works as it's just a spacer until the filleting and tabbing is in. Tim Lackey at Lackey Sailing, LLC | Boatbuilders, Boat Restorers, and Caretakers of Classic Boats does all his this way as well on his restorations.

mitiempo · #8 (**permalink**) 01-29-2010

If you just want to strengthen the panels a bit just hot glue some foam where you want the frame and glass over it with a couple of layers of biax and epoxy. Why are you reinforcing it? Does it flex more than you think it should or are you planning to go offshore? Like you say the problem is access with the liner in the way.

xact · #9 (**permalink**) 01-29-2010

I am taking it across the Atlantic and I just feel the liner and tabbing is inadequate I had to re-glass some tab already so I know it is moving a bit. Aft of the main bulkhead their is no other bulkhead for the main and aft part of the boat.
And I beat on it quite a bit
The foam is a good idea I would have to round off the corners at the top though, probably be stronger than the hollow semicircle then?

boatpoker · #10 (**permalink**) 01-29-2010

Taking a Tanzer 26 trans Atlantic is a brave thing to do. These are built to be not much more than weekenders and are built very lightly. I hope you are not only reinforcing the structure but also the rudder and its mounting and thats a pretty weak little rudder mounted on thin gudgeons and very light pintles .... its not going to stand up against Atlantic waves. The rigging and chainplate mountings are also very light for that kind of crossing.

Good luck.